Sci 100a Lab Book P2

Online SCI 100A: Survey of Bioscience Laboratory Laboratory Manual (Version 2.0)

National University

Written by: Michael R. Maxwell 2005 Revised: 2007

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Table of Contents Lab 1: Metric Measurement

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Lab 2: Enzymes

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Lab 3: Human Genetics

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Lab 4: Fungi

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Lab 5: Seed-bearing Plants

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Lab 6: Animals

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Lab 7: Human Anatomy

39

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Foreward This laboratory manual is written specifically for students taking the online course SCI 100A. Materials and activities are designed to be performed at home with minimal cost and hazard to students. This manual's content is based on the regular assigned manual for SCI 100A: Mader, S. S. 2001. Biology: laboratory manual, seventh edition (customized). McGraw-Hill; New York. Students should also have the textbook for SCI 100, as concepts in 100A will be referred to this textbook. The textbook for SCI 100 is: Mader, S.S. Biology. McGraw Hill; Boston, MA. Juliann Downing of National University provided assistance in the writing of this manual.

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Materials needed Students need to obtain the following materials for successful completion of this course. Emphasis has been placed on items that are easily found in the house, or can be purchased at minimal cost from local stores. Item Ruler (with metric) One whole potato Hydrogen peroxide (1 pint, 473 ml) Household ammonia White vinegar Disposable, clear cups Sharp knife Cutting board One large mushroom (common or shiitake) Large pine cone with open “scales” Fascicle (bundle) of pine needles Measuring cup Red food coloring Blue food coloring Salt Celery stalk Paper towels Pea pod (sugar snap or snow pea) Dry lima beans (3) Disposable plates Two of the following animals: Garden snail Squid Earthworm or night crawler (large) One crustacean House cricket (adult) Ladybug Mackerel

Availability Household Household Household Household Household Household Household Household

Approx. cost OR OR OR OR

Grocery Grocery (First Aid) Grocery (Cleansers) Grocery

$ 0.70 $ 1.00 $ 1.65 $ 1.29

Grocery

$ 0.20

Household/Neighborhood Household/Neighborhood Household Household Household Household Household OR Grocery Household Grocery Grocery Household Household/Neighborhood Grocery Household OR Bait store Grocery Pet store Household/Neighborhood Bait store

$ 1.00 $ 0.10 $ 0.50

$ 4.00 $ 2.70 varies $ 0.10 $ 3.00

Estimated total cost of materials: less than $10.00

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Lab 1: Metric Measurement Materials needed Ruler (with metric) Introduction Accurate measurement of the natural and physical world is fundamental to science. Modern scientists use the metric system in their measurements. The metric system was developed in France in the late 1700s, and is now commonly used in most countries. A main advantage of the metric system is that it is based on multiples of 10. This is much easier than the English system of 12 inches to the foot, 16 ounces to the pound, and 16 cups to the gallon. For Americans, the metric system presents a difficulty because its basic units are not easily visualized. In this laboratory, you will develop an understanding of the metric system and use it to measure common objects. This laboratory is based on pp. 7-11 of the lab manual Mader (2001). Metric units The basic measurements of the metric system are: 1. Length, expressed in meters (m). 2. Mass (weight), expressed in grams (g). 3. Volume (capacity), expressed in liters (l). These units have the following English equivalents. One meter is roughly 3 feet (1 yard), or slightly longer than one pace. One gram is very light, about the same weight as a slender finger ring. Standard weights are often expressed in kilograms (1,000 grams). One kilogram is roughly 2 pounds. One liter is roughly 1 quart, so there are about 4 liters in 1 gallon. For each of these units, large or small amounts are expressed by prefixes that reflect multiples of 10, as the following table shows. Prefix Symbol gigaG mega- M kilok hecto- h dekada decicentimillimicro-

d c m μ

Power of 10 109 = 1,000,000,000 106 = 1,000,000 103 = 1,000 102 = 100 101 = 10 100 = 1 10-1 = 0.1 10-2 = 0.01 10-3 = 0.001 10-6 = 0.000001

Length

Mass

Volume

kilometer (km)

kilogram (kg)

kiloliter (kl)

meter (m)

gram (g)

liter (l)

centimeter (cm) centigram (cg) centiliter (cl) millimeter (mm) milligram (mg) milliliter (ml)

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Using these prefixes, the following exact conversions can be made: 1 meter = 100 cm = 1,000 mm = 3.28 feet = 39.37 inches 1 inch = 2.54 cm [1 cm is slightly less than a half-inch] 1 mile = 1.61 km = 5,280 feet 1 kilometer = 1,000 m = 0.621 miles [1 km is somewhat longer than a half-mile] 1 kilogram = 1,000 kg = 2.2 pounds 1 liter = 1,000 ml = 1.06 quarts = 0.264 gallons Temperature Similar to the metric system is the Celsius scale of temperature. This system was developed by the Swedish astronomer Anders Celsius in 1742. Nearly every country in the world uses the Celsius system. Thus, it becomes somewhat confusing for traveling Americans when the morning news in the hotel announces a "nice day" of 24 degrees. This sounds cold, but 24º C is actually 75º F. The Celsius system is based on the freezing and boiling points of water: Celsius (ºC) Fahrenheit (ºF) Water boils 100 212 Water freezes 0 32 1 Absolute zero -273 -395 Exact conversions between the two scales are: ºC =

5 (ºF - 32º) 9

ºF = (

9 ºC) + 32º 5

A short-cut to estimating Fahrenheit from Celsius is the following: ºF ≈ 2׺C + 30.

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Absolute zero is the temperature at which all molecular motion stops.

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Lab Report 1 1. Using a metric ruler, determine the length of the following items: cm mm meters Your favorite shoe Your index finger A pencil Fingernail of your pinky Width of a credit card

inches

2. Complete the conversions in this table. The first row has been done. m miles feet km 2.0 km 2.0 2,000 1.24 6,558 705 m 3.25 miles 300 feet 3. Complete the conversions in this table. g kg 5.0 kg 400 g 50 pounds 4. Complete the conversions in this table. ml l 6.0 liters (l) 600 ml 3 gallons

pounds

gallons

6. Complete the conversions in this table. °F °C 10 °C 27 °C -2 °C 27 °F 95 °F

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Lab 2: Enzymes Materials needed One whole potato Hydrogen peroxide (1 pint, 473 ml) Household ammonia White vinegar 3 disposable clear glasses Tap water Sharp knife Ruler (metric) Marker Introduction An enzyme is a molecule that increases the rate of chemical reactions. Enzymes are extremely important for all organisms, because they regulate the rates of digestion, protein synthesis, etc. The action of an enzyme is sensitive to environment conditions. Temperature, for example, can increase the activity of an enzyme. Another important factor is pH, which is a measurement of the acidity of a liquid solution. The pH scale ranges from 0 to 14. A low pH value means a highly acidic solution; a high pH value means a highly alkaline (basic) solution. Both highly acidic and highly alkaline solutions are corrosive. Pure water, which is neither acidic or alkaline, is neutral, being pH = 7. The following table gives the pH values of common substances. pH Very acidic 0 1 2 3 4 5 6 Neutral 7 8 9 10 11 12 13 Very alkaline 14

Examples Battery acid Lemon juice; gastric juice (in stomach) Vinegar; Grapefruit juice Tomato juice Coffee Urine; saliva; milk (pH = 6.5) Distilled water; human blood; semen (pH = 7.4) Egg white; seawater (pH = 8.4) Milk of magnesia (pH = 10.5) Household ammonia (pH = 11.7) Household bleach Oven cleaner (pH = 13.5)

Each enzyme has a pH at which the rate of the reaction is optimal. Any higher or lower pH affects the structure of the enzyme, leading to reduced activity. In the following experiment, you will work with the enzyme catalase. Catalase is an enzyme present in cells that speeds the breakdown of hydrogen peroxide (H2O2), a toxic chemical, into

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water and oxygen. A potato will serve as the source of catalase. As the reaction occurs, easily observable bubbling will develop. 2 H2O2 hydrogen peroxide

-------------------->

2 H2O

catalase (in potato)

water

+

O2 oxygen

This laboratory was developed by Juliann Downing of National University. It is based on pp. 66-67 of the lab manual Mader (2001). Information on enzymes can be found in Chap. 6 of the Mader textbook. Activity 1. CAUTION: AMMONIA IS CORROSIVE. Prolonged exposure to vapors may cause breathing difficulties. Open a window when conducting this experiment. Contact with skin may cause irritation. If contact occurs, wash immediately with lots of water.

2. Peel the skin off of the potato with the knife. Chop the potato into small chunks. 3. Label each cup: #1: Potato + Vinegar + H2O2 #2: Potato + water + H2O2 #3: Potato + Ammonia + H2O2 4. Mark each cup with a dash at the 1-inch, 2-inch, and 3-inch heights (i.e., 2.5-cm, 5.0cm, 7.5-cm). 5. Fill each cup with approximately 1 inch (2.5 cm) of potato. 6. Fill the cups as follows: #1: vinegar to the 2-inch (5.0-cm) mark. #2: tap water to the 2-inch (5.0-cm) mark. #3: ammonia to the 2-inch (5.0-cm) mark. 7. Let the cups sit for 5 minutes to allow the potato to soak up the liquid. 8. Fill all cups to the 3-inch (7.5-cm) mark with hydrogen peroxide, H2O2. The layering of the cups should now be as follows: Cup 1 Hydrogen peroxide Vinegar Potato

Cup 2 Hydrogen peroxide Water Potato

Cup3 Hydrogen peroxide Ammonia Potato

9. Observe bubbling for 2-3 minutes. Then, complete Question 1 of Lab Report 2.

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Lab Report 2 1. Fill in the following table. Describe the activity of catalase with the following terms: No bubbling Moderate bubbling Good bubbling Very good bubbling Cup 1 2 3

Contents

pH

Catalase activity

2. Bubbling indicates the formation of what chemical?

3. Describe the activity of catalase as pH increases.

4. Briefly describe how you would go about pinpointing the exact pH at which catalase is the most active.

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Lab 3: Human Genetics Materials needed None Introduction Humans, like many other organisms, are diploid. Being diploid, humans inherit two genetic forms (alleles) of a gene, one from each parent. In this laboratory, you will investigate some common human genetic features. This laboratory is based on pp. 123-126 of the lab manual Mader (2001). This material is covered in Chaps. 11 & 12 in the Mader textbook. Genotype and phenotype The diploid condition means that, in most of the cells in the body, there are two pairs of every chromosome. The two chromosomes in each pair are homologous chromosomes. Homologous chromosomes are typically the same length and shape, and have genes at the same locations. Genes are regions of chromosomes that are ultimately responsible for the body's anatomy and physiology. The actual genetic sequence at a gene is an allele. Homologous chromosomes might have the same genetic sequence at a particular gene, thereby having the same allele for this gene. In this case, the chromosomes are homozygous for the gene. Alternatively, homologous chromosomes might differ in the genetic sequence at a gene, thereby representing two different alleles for the same gene. In this case, the chromosomes are heterozygous. Any given combination of alleles is the genotype. The phenotype is the observable result or traits of the allele combinations. To illustrate these ideas, consider a simplified depiction of eye color. Suppose there are two alleles, B and b. The genotypes BB and Bb result in brown eyes, while bb results in blue eyes. In this example, the B allele is dominant, because the heterozygote (Bb) shows brown color. The b allele is recessive. Because chromosomes are passed from parent to child, one can predict the relative likelihood of children having certain traits, given that the genotypes of the parents are known. Such an analysis involves a Punnett square, where the alleles of both parents are combined in all possible combinations.

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Continuing with the eye color example, suppose a brown-eyed man (Bb) couples with a browneyed woman (Bb). This can be described by the following Punnett square: Brown-eyed man (Bb) × Brown-eyed woman (Bb) Woman (Bb)

B

b

B

BB (brown)

Bb (brown)

b

Bb (brown)

bb (blue)

Man (Bb)

A common, and generally valid, assumption is that equal numbers of B and b sperm cells are produced by the man. Similarly, the woman is assumed to be equally likely to ovulate an egg containing a B or b allele. Under these assumptions, the man and woman are 25% likely to produce a BB child, 50% to produce a Bb child, and 25% to produce a bb child. These are the genotype frequencies. But, because BB and Bb both result in brown eyes, the phenotype frequencies are different: 75% to produce a brown-eyed child and 25% to produce a blue-eyed child. For the lab report, you will collect data on three human traits: tongue-rolling, earlobe attachment, and thumb flexibility ("hitch-hiker's thumb").

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Tongue-rolling Phenotype: "roll" (can curl sides of tongue). Genotype: RR or Rr. Phenotype: "no roll" (cannot curl sides of tongue). Genotype: rr.

Figure 3.1. Tongue-rolling. The"roll" phenotype (genotype is RR or Rr). [Image taken from the Internet.]

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Earlobe attachment Phenotype: "Unattached." Genotype: UU or Uu. Phenotype: "Attached." Genotype: uu.

Figure 3.2. Earlobe attachment. [Image taken from the Internet.] A) "Unattached" phenotype (genotype is UU or Uu). B) "Attached" phenotype (genotype is uu).

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Thumb flexibility ("hitch-hiker's thumb") Phenotype: "No hitch-hiker." Genotype: TT or Tt. Phenotype: "Hitch-hiker" (last digit of thumb can extend backwards). Genotype: tt.

Figure 3.3. Thumb flexibility. [Images taken from the Internet.] Left: "No hitch-hiker" phenotype (genotype is TT or Tt). Right: "Hitch-hiker" phenotype (genotype is tt).

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Lab Report 3 1. Complete the following table of phenotypes for you, any blood relatives (i.e., parents, siblings, cousins, children, etc.), and at least five unrelated “Others” (e.g., spouse, friends, co-workers, etc.). For Relatives and Others, record the number of individuals that show each phenotype.

Trait

Your Phenotype

Possible Genotypes

Roll tongue Cannot roll tongue

RR or Rr rr

Unattached earlobes Attached earlobes

UU or Uu uu

No hitch-hiker thumb Hitch-hiker thumb

TT or Tt tt

Relatives’ Phenotypes

Others’ Phenotypes

2. From the above table, are there any alleles that are particularly common or uncommon among you and your relatives, compared to the alleles of Others?

3. List your phenotype and possible genotypes for each of the three traits. Based on your genotypes, what can you conclude about your parents’ genotypes for each trait?

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Lab 4: Fungi Materials needed Sharp knife Cutting board Large mushroom: common (Agaricus sp.) or shiitake (Lentinus edodes) Introduction The Kingdom Fungi consists of organisms that are heterotrophic and usually multicellular. Fungi differ from animals in that fungi digest organic matter outside of their bodies, then ingest the dissolved nutrients. For example, a mushroom growing on a tree is actually secreting enzymes that are dissolving the surface of the tree. In contrast, animals typically swallow food, then digest it inside the body. Many fungi are saprotrophic, meaning that they decompose dead organic matter. Fungi and bacteria are ecologically important as decomposers, because they break down the complex molecules of plant and animal bodies into simpler molecules. These simpler molecules are then used by plants. Other fungi, such as the fungus that causes athlete’s foot, are parasitic, meaning that they extract nutrients from the living tissue of another organism. The Kingdom Fungi consists of three phyla: Zygomycota (many kinds of molds and mildews), Ascomycota (mushrooms that look like cups or chalices), and Basidiomycota (common mushrooms). Yeasts are single-celled fungi, and usually belong to the Ascomycota. In this laboratory, you will investigate the gross anatomy of a large mushroom (i.e., a member of the Basidiomycota). This laboratory is based on pp. 219, 224-225 of the lab manual Mader (2001). This material is covered in Chap. 23 of the Mader textbook. Activity: mushroom dissection 1. Obtain a large edible mushroom, either a common one or a shiitake. Refer to Figure 4.1 as you perform this activity. 2. The first thing to notice is what is not on your mushroom. Your mushroom will most likely be cut at the bottom. What has been cut off is the mycelium. The mycelium is a network of thin filaments (hyphae). One hypha is a thin linear “chain” of cells. Bundles of hyphae comprise the body of the mushroom. The mycelium serves as the “roots” of the mushroom: it anchors into the soil and absorbs nutrients from the environment. 3. Identify the stalk and cap. The stalk supports the cap, elevating it from the substrate. The cap produces spores. A spore is a haploid cell that clones itself to make a new mycelium, from which a new stalk and cap emerge. 4. If you have a shiitake mushroom, the gills on the underside of the cap will be obvious. If you have a common mushroom, peel away the white tissue that connects the cap to the stalk. This exposes the dark gills.

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5. The gills are flat “sheets.” On the surface of these sheets are microscopic basidia (you won’t be able to see them). The basidia are the structures that make spores. Once spores are made, they are released to travel through the air to begin as a new mushroom. 6. Perform a longitudinal cut through the mushroom (i.e., cut it in half long-ways). Gently peel apart the outer surface of the stalk. Notice that it is composed of “threads.” These threads are bundles of hyphae. 7. Examine the interior region of the stalk. Notice that there are no “veins” or vascular tissue, as in plants (e.g., celery stalks). In mushrooms, nutrients and water do not flow in specialized veins or canals. Rather, nutrients and water are absorbed by the mycelium, and then are transported cell-by-cell through the stalk and to the cap. This is possible because fungal cells have walls, but there are holes in the walls. Thus, cytoplasm containing nutrients and water can flow freely between cells.

Figure 4.1. General anatomy of a mushroom. [From Fig. 21.4, p. 335 of Starr (2003).]

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Lab Report 4 1. List four ways that Fungi are similar to plants.

2. List three differences between Fungi and plants.

3. List four facts that you learned about Fungi, but did not know before.

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Lab 5: Seed-bearing plants Materials needed Sharp knife Cutting board Large pine cone with open “scales” Fascicle (bundle) of pine needles 2 household cups (may be disposable) Measuring cup Red food coloring Blue food coloring Salt Celery stalk Paper towel Pea pod: sugar snap pea or snow pea Dry lima beans (3) Introduction The Kingdom Plantae consists of organisms that are photosynthetic, multicellular, and predominantly terrestrial. Because plants produce glucose (a simple sugar) through photosynthesis, they are the basis of ecosystems on land. All plants have green pigmentation that absorbs sunlight to begin the process of photosynthesis. The Kingdom Plantae consists consist four main groups. The first are the bryophytes (e.g., mosses). Bryophytes do not have vascular tissue, which is the internal system of “pipes” found in most plants (this is the “stringy” stuff of celery stalks). The remaining three groups all have vascular tissue. The “ferns” are vascular plants that do not produce seeds. In ferns, fertilization occurs, and the embryo develops relatively unprotected. The two remaining groups produce a seed, which is a complex of the developing embryo, its food source (endosperm), and a protective seed coat. The gymnosperms (“naked” + “seed”) produce seeds that are exposed to the environment. Gymnosperms include large trees such as pines, firs and redwoods. The last group, the angiosperms (“encased” + “seed”), produce fruits and flowers. Angiosperms envelope seeds within a fruit. The fruit is actually the swollen tissue of the ovary of the female flower. Most modern plants are angiosperms. In this laboratory, you will examine the basic anatomy of a gymnosperm and an angiosperm. This laboratory is based on pp. 245-258 of the lab manual Mader (2001). This material is covered in Chaps. 24 & 25 of the Mader textbook. The lab activity with celery was inspired by the website: www.marketplaceforthemind.state.pa.us/ m4m/lib/m4m/documents/labs/Stem_Transport.pdf The lab activity with the lima bean was inspired by the website: www.troy.k12.ny.us/thsbiology/labs_online/school_labs/seed_lab_school.html

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Activity: anatomy of pine 1. Obtain a pine cone and a fascicle (bundle) of pine needles. Refer to Figure 5.1 as you perform this activity. 2. Examine the fascicle of pine needles (Figure 5.1). A pine needle is actually a leaf. It has green pigmentation for photosynthesis. It is skinny, leathery, and coated with a sticky resin to help retain water. Pine needles are bound together in a bundle (fascicle). Different species have different numbers of needles per fascicle. For example, white pines (Pinus strobus) have five needles per fascicle, while red pines (Pinus resinosa) have two needles per fascicle. 3. Examine the large pine cone (Figure 5.1). It should be large enough to fit into your palm, and its woody “scales” should be open. Pine trees produce two kinds of cones: pollen cones and seed cones (or ovulate cones). Pollen cones are small – they often are not much bigger than the last digit of your pinky finger. These cones produce pollen grains, which contain sperm. You should have a larger cone, the seed cone. Each woody “scale” of the seed cone typically produces two eggs at its base. Before the eggs are fertilized, the seed cone is closed up. Pollen grains blow into the cracks between the closed scales, and fertilize the eggs. The fertilized egg then develops into a seed, and the scale opens. The scales are called sporophylls (“spore” + “leaf”). 4. Break off a few scales near the top of the cone. Examine the base. You should see two indentations where the seeds used to be. Examine or break off a few scales near the bottom of the cone. There may be seeds present (Figure 5.1). The pine seed has a “wing.” This enables the seed to disperse away from the parent plant via the wind. This is why the scales open up once the seed develops. 5. A seed cone usually does not release all of its seeds at once. Thus, part of the cone, usually the top, is often more “open” than other parts. Because pine cones rely on the wind to disperse seeds, it is important that the “wing” of the seed stays dry. Pine cones protect developing seeds from becoming waterlogged through a passive reaction. a. Place your open seed cone into a cup of tap water. b. Record: Time into water _________ Cone appearance _________________________ c. Let the cone sit in the water for at least 30 minutes. b. Record: Time out of water _______ Cone appearance _________________________

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Figure 5.1. Pine tree basic anatomy. [From p. 597, N.A. Campbell & J.B. Reece. 2005. Biology, 7th edition. Benjamin Cummings; San Francisco.]

Activity: vascular tissue 1. Most plants have vascular tissue. Vascular tissue is found in the interior of the roots, stem, and leaves. Vascular tissue consists of two types: xylem (transports water) and phloem (transports sugar and other organic nutrients). 2. Obtain two cups. Fill each cup with 400 ml of tap water (somewhat less than 2 cups). Add 32 drops of red food coloring into one cup. Add 32 drops of blue food coloring into the other cup. Add a spoonful of salt into each cup. 3. Obtain a stalk of celery. This is the stem of the plant. Cut a 1-cm piece (about one-half inch) off the bottom and the top of the stalk. Examine the end of the celery stalk. Notice the dark green “dots.” Each dot is a cluster of vascular tissue (Figure 5.2). 4. Carefully, split the stalk up the middle about half-way. Our stalk should now have two “legs.” Place the red and blue cups together. Gently place one “leg” into the red cup, and the other “leg” into the blue cup. The celery should now be “straddling” the two cups (Figure 5.2). 5. Let the celery sit in the cups for at least 12 hours. 22

6. Examine the top of the celery stalk. Record your observations: ___________________________________________________________________________ ___________________________________________________________________________ 7. Make a cross-section cut where the celery stalk has not been split. Record your observations: ___________________________________________________________________________ ___________________________________________________________________________ 8. Tear apart the celery stalk. Notice the feel of the vascular tissue, and how the food coloring lies within it.

A)

B)

Figure 5.2. Celery activity. A) Cross section of a celery stalk. The dark green circles are clusters of vascular tissue. B) Diagram of the celery stalk “straddling” the cups with red and blue coloring.

Activity: seeds 1. Gymnosperms and angiosperms produce seeds. In angiosperms (flowering plants), several structures are involved in the formation of a seed (Figure 5.3). First, an egg is formed in the ovary, which is part of the carpel (the female organ of a flower). Within the ovary are many ovules. Each ovule creates an egg within. When a pollen grain lands at the tip of the carpel (stigma), two sperm are released. The sperm tunnel down towards an ovule to fertilize an egg. Once the egg is fertilized, the ovule develops into a seed. The ovary of the flower often develops into a fruit, which is usually an edible package of swollen tissue that surrounds many seeds. 2. Obtain a sugar snap pea pod, or a snow pea pod. This is the fruit that develops from the pea flower (Figure 5.4). In this case, the fruit is not as sweet or as juicy as an apple. Cut along the curve of the pod. This exposes the seeds (peas) on the inside. You should be able to

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crack the peas in half. This reveals that the seed is composed of two cotyledons (seed “leaves”). The cotyledon becomes the main food source as the seed starts sprouting. 3. Angiosperm plants are divided into dicots (Class Dicotyledonae) and monocots (Class Monocotyledonae). There are 180,000 species of dicots, including many flowers, shrubs, and trees. Dicots are distinguished by seeds with two cotyledons (e.g., bean, peanut, pea), leaves with veins having a branching pattern (e.g., maple, oak), and flower parts in multiples of four or five (e.g., four petals of poppies, five petals of wild roses). There are 80,000 species of monocots, including grasses and important crops (e.g., wheat, corn, rice), palms, and orchids. Monocot seeds have one cotyledon (e.g., corn kernel), leaves with parallel veins (e.g., blade of grass), and flower parts in multiples of three (e.g., six petals on lilies). 4. Obtain a few dry lima beans. Soak them in a cup of tap water for at least 8 hours. 5. Gently dry the beans on a paper towel. With your finger, you should be able to gently peel off the outer seed coat (if you cannot, soak the bean for 1-2 more hours). 6. Using a knife, carefully cut along the curvature of the bean. You should then be able to break the bean in half. Each half is a cotyledon, which has become swollen with nutrients from the endosperm. 7. Examine the embryo (see Figure 5.5). At minimum, you should be able to recognize the leaflike tip of the epicotyl. Look for the hypocotyl and the radicle.

Figure 5.3. Seed and flower anatomy. The carpel is the entire upright green organ of the flower. [From Fig. 22.14-a, p. 351 of Starr (2003).]

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Figure 5.4. Pea fruit. The pea fruit (pod) develops from the carpel of the flower. [From p. 779, N.A. Campbell & J.B. Reece. 2005. Biology, 7th edition. Benjamin Cummings; San Francisco.]

Figure 5.5. Bean. [From p. 778, 780, N.A. Campbell & J.B. Reece. 2005. Biology, 7th edition. Benjamin Cummings; San Francisco.] Left: Anatomy of the bean. Right: Sprouting of the bean.

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Lab Report 5 1. Answer the following questions about seed dispersal. a) Why is it important for a parent plant to disperse its seeds?

b) What do gymnosperms use to disperse seeds? What do angiosperms use?

c) Some gymnosperms, such as redwoods, release seeds only after a fire. Suggest a reason why this is done.

2. Which direction does xylem flow? What about phloem?

3. Use Figure 5.5 to answer this question. What is the function of: a) radicle?

b) hypocotyl?

c) epicotyl?

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Lab 6: Animals Materials needed Disposable plates Disposable cup Sharp knife Paper towels Two of the following: Garden snail Squid Earthworm or night crawler (large) One crustacean (e.g., whole shrimp, crab, lobster, crayfish) House cricket (adult) Ladybug Mackerel

Phylum Mollusca (Class Gastropoda) Mollusca (Class Cephalopoda) Annelida (Class Oligochaeta) Arthropoda (Subphylum Crustacea) Arthropoda (Subphylum Uniramia) Arthropoda (Subphylum Uniramia) Chordata (Subphylum Vertebrata)

Introduction The Kingdom Animalia consists of organisms that are heterotrophic, multicellular, and typically mobile with sexual reproduction. Most of the known species on Earth, roughly 67%, are animals. Of all animal species, about 98% are invertebrates. There are 12 phyla of animals listed in Appendix B of the Mader textbook, which is about onethird of the described animal phyla. Introductory biology courses typically cover about nine animal phyla, which are the following: Body Examples Symmetry Support Head Mouth Anus Phylum Porifera Sponges None Glass-based fragments No No No Cnidaria Jellyfish Radial Mesoglea (“gel”) No Yes No Platyhelminthes Flatworms Bilateral Body muscles Yes Yes No Nematoda Roundworms Bilateral Body muscles Yes Yes Yes Mollusca Snail, clam Bilateral Shell; body muscles Yes Yes Yes Annelida Earthworms Bilateral Hydrostatic skeleton Yes Yes Yes Arthropoda Chelicerata Spiders Bilateral Exoskeleton Yes Yes Yes Crustacea Crabs Bilateral Exoskeleton Yes Yes Yes Uniramia Insects Bilateral Exoskeleton Yes Yes Yes Echinodermata Starfish Radial Endoskeleton No Yes Yes Chordata Vertebrates Bilateral Endoskeleton Yes Yes Yes In this laboratory, you will examine the basic external anatomy of at least two different animals. You are to choose two of the animals listed in the “Materials required” section. You may choose whichever two are the most convenient to find, least creepy, least slimy, etc. The written activities are somewhat brief. Diagrams are given, and you are to locate specified body parts. No dissection of live animals is required. The only dissections are those of the squid and mackerel, which you will presumably buy already dead.

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This laboratory is based on pp. 279-299, 308-323 of the lab manual Mader (2001). This material is covered in Chaps. 29-31 of the Mader textbook. Activity: garden snail Phylum: Mollusca Class: Gastropoda Order: Pulmonata Family: Helicidae Genus & species: most likely Helix aspersa

Figure 6.1. Snail anatomy. [Image taken from Internet.]

1. The Mollusca are “squishy and slimy” organisms. Molluscs may have a well-defined head (e.g., snail, squid) or not (e.g., clam), and may have a hard shell (e.g., snail, clam) or not (e.g., squid, octopus, slug). 2. On the garden snail, locate the foot. The foot is a basic feature of all molluscs. Snails secrete “slime” to facilitate movement. 3. Locate the shell. Within the shell is the visceral mass – the main part of the body that includes digestive and reproductive organs. Draped over the visceral mass is the mantle – tissue that secretes a hard shell (if a shell is present). 4. On the snail, locate the following: eyestalks, tentacles, respiratory pore. 5. Observe how the snail crawls. Observe how it retracts into its shell when disturbed. The anus of the snail actually empties out over the snail’s head, so that the snail does not foul itself when retracted into the shell.

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6. If you took the snail from the outdoors, put it back. Activity: squid Phylum: Mollusca Class: Cephalopoda Order: Teuthoidea Family: Loliginidae Genus & species: varies, but the common commercial squid in California is Loligo opalescens

Figure 6.2. Squid anatomy. [From p. 285 of the lab manual Mader (2001).] 1. WEAR OLD CLOTHES. SQUID ARE SLIMY AND HAVE AN INK SAC. THE INK IS NOT TOXIC, BUT IT WILL STAIN. WORK ON A DISPOSABLE PLATE PLACED ON AN OLD TABLECLOTH OR LAYER OF PAPER TOWELS.

2. The squid’s body design is that of a predator. Note the “torpedo” shape of the body, which helps reduce water resistance when moving. Squids also secrete mucus along the body to reduce water resistance. The squid has a well-defined head and large eyes. 3. Squids rely on jet propulsion for fast movement. They take water into the body space behind the head, then force it out through the muscular funnel. The funnel can rotate to allow for instant rapid forward or backward movement. Squids also have fins at the

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posterior end of the body. These are flaps of tissue that enable the squid to hover and move more slowly. 4. The squid’s foot is modified into arms and tentacles. Locate the two long, dangling tentacles that may still be present. Touch the end of a tentacle. It may slightly stick to your finger. Squids use tentacles for initially seizing prey. There are powerful suckers, often with accompanying hooks, on the tentacles. Captured prey is brought to the squid’s mouth. The squid then holds the prey with its eight shorter arms. Squids also use their arms for fighting, grabbing mates, and manipulating objects in the environment. 5. Dissect the squid by laying it on its “back” (the slightly hardened surface) on a disposable plate or surface. Cut its body wall open, as if you were “unzipping” the squid. This cut will expose the squid’s internal organs. 6. Locate the following (starting at the head and moving along the body): a. Beak. At the base of the arms is the mouth. Gently cut around this area to extract a parrot-like beak. Squids chew their prey with this beak. b. Gills. Two feathery gills should be obvious on either side of the internal body. c. Ink sac. A slender, silvery sac is located about where the gills join the body. Squids and other cephalopods squirt ink to confuse predators. d. Gonad. The gonad is at the end of the body. It will either be a long, thin white flap (testes), or a bundle of yellow-orange eggs (ovary). e. Pen. Squids do have a shell, but it is greatly reduced. Gently cut into the hardened surface of the squid. The hardness is due to a thin, plastic-like shell, or pen. You can extract the pen by cutting off one end of the squid’s hardened surface, and pulling out the pen. Notice that the pen looks like a feather, or an old-fashioned writing quill or pen. You can actually use the pen to write – cut open the ink sac, dab the pen, and scratch out a few words on a disposable surface. CAUTION: THE INK CONTAINS MUCUS, SO IT WILL STAIN SURFACES AND CLOTHES. 7. Dispose of the squid. It will start stinking, so don’t let it sit overnight in the kitchen trash container. Activity: earthworm or night crawler Phylum: Annelida Class: Oligochaeta Order: Lumbriculida Family: Lumbriculidae Genus & species: Lumbricus sp. 1. The Annelida are the segmented worms, which include the common earthworm, marine worms, and leeches. The hydrostatic skeleton of annelids is like a chain of doughnuts arranged to form a tube. Each “doughnut” is filled with fluid. Annelids use body muscles to compress and squeeze the fluid to move forward.

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2. Obtain an earthworm or a large night crawler. Notice the segments that are obvious on the body surface. Clean the worm by dunking it in a cup of tap water and then drying it on a paper towel. Rub your fingers along the worm, starting from the middle and moving towards the end. Towards the end, the worm should have a rough, scratchy, “5 o’clock shadow” feel. There are stiff bristles, called setae or chaetae, on the worm’s surface. These bristles anchor into the soil, to stabilize one end of the body while the other end is moving forward. 3. Observe the worm’s movement. Notice that each segment of the body is capable of constriction, compression, and elongation. Circular muscles contract to constrict a segment. Longitudinal muscles contract and relax to allow for compression and elongation, respectively. Rhythmic waves of muscle contractions are called peristalsis. 4. Locate the clitellum (the “band-aid” portion of the body). Many worms, including earthworms, are hermaphrodites. Mating occurs by two individuals lying together to exchange sperm. The clitellum secretes mucus to hold the worms together during sperm exchange. 5. Notice the blood vessels that are visible. Annelids have a closed circulatory system, with the blood being confined in vessels. A system of multiple hearts pumps the blood. Like humans, annelids have hemoglobin in their blood, so their blood is red. 6. You can put the earthworm or night crawler back in the soil. They are very important for soil quality, as they aerate the soil by tunneling through it. Also, they pass particles of dirt through their digestive systems to feed. So, worms are the best friends of farmers and gardeners, because they improve the growing conditions for plants without harming the plants themselves.

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Activity: one crustacean Phylum: Arthropoda Subphylum: Crustacea

Figure 6.3. Anatomy of generalized crustacean. [From Figure 23.25, p. 374 of Starr (2003).]

1. The Crustacea are arthropods that are mostly aquatic, especially marine. Like other arthropods, they have a rigid exoskeleton and jointed appendages. They use the appendages for many functions, including food handling, movement, and sperm transfer. Crustaceans are distinctive for having unique appendages at the mouth and two pairs of antennae. 2. This activity is a general examination of external anatomy, because you may have a crayfish, crab, shrimp, etc. Refer to the generalized diagram of crustacean anatomy (Figure 6.3), and find the following body parts: a. Cephalothorax (body region) b. Carapace (hard covering of cephalothorax) c. Long pair of antennae d. Shorter pair of anntenules e. Appendages near the mouth (used for feeding) f. Walking legs g. Abdomen (body region) h. Swimmerets i. Tail fan

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Activity: house cricket or ladybug Phylum: Arthropoda Subphylum: Uniramia Superclass: Insecta Class: Pterygota In terms of the number of species, the Insecta is the most successful group of organisms on the planet. It is estimated that roughly 50% of all known species are insects. Roughly 50% of all known insect species are beetles. Insects share the common arthropod features of exoskeleton and jointed appendages. The insect body consists of three regions: head, thorax, and abdomen. The head contains sensory (antennae, eyes) and feeding structures. The thorax begins after the head and contains the organs of movement: legs and wings. Insects typically have three pairs of legs and two pairs of wings. The abdomen is the insect’s “belly”, which contains digestive, respiratory, and reproductive organs. House cricket Order: Orthoptera Family: Gryllidae Genus & species: Acheta domestica

Figure 6.4. House cricket anatomy (adult female). [From p. 374, C.P. Hickman and L.B. Kats. 2004. Laboratory studies in integrated principles of zoology, 12th edition. McGraw Hill; New York.]

1. Examine your cricket. It should be an adult (i.e., it should have fully formed wings). The female has a long “stinger” organ. This is not actually a stinger, and it cannot hurt you.

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It is the ovipositor, which the female squeezes eggs through when it is time to lay. The female’s top wings look uniform. The adult male’s top wings have a “swirled” look. This is due to structures on these wings used to make the characteristic “chirp” calls. The male rubs these wings together, scraping hardened areas together. In contrast, a male grasshopper rubs his hind legs together to make calls. Grasshoppers have longer and more powerful hind legs for jumping than do crickets. 2. On your cricket’s head, locate the antennae (used for olfaction), compound eyes (color, image, and movement detection), and ocelli (simple eyes that detect light intensity and direction). Examine the cricket’s mouth and notice the various appendages (palps) that it uses for feeding. 3. The thorax consists of three segments. A shield, the pronotum, covers the dorsal surface of the first thoracic segment (prothorax). Each segment of the thorax has a pair of legs. On one leg, locate these parts: femur, tibia, tarsus. Like most insects, the cricket has two pairs of wings. The middle thoracic segment (mesothorax) has the hardened top wings (forewings, outerwings, elytra or mesothoracic wings). The last thoracic segment (metathorax) has the softer inner wings (hindwings, underwings or metathoracic wings). 4. On the cricket, locate the ovipositor (if female) and cerci (spike-like appendages at the end of the abdomen). Look at the cricket from the side. Along the abdomen, you should see small “pinholes” on each segment. These openings are spiracles, through which the insect breathes. Thus, insects do not breathe through their mouths or any “nose” structure. Ladybug (ladybird beetle) Order: Coleoptera Family: Coccinellidae Genus & species: various; common genera are Hippodamia and Coccinella in California

Figure 6.5. Ladybug anatomy. [Image taken from the Internet.]

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1. The terms in this activity follow that for the house cricket (above). Refer to steps 2-4 of the house cricket activity for explanations of body parts. 2. A dorsal view of the ladybug reveals two obvious body parts: the red top wings (outerwings or elytra) and a black and light fore portion. The fore portion is actually the head and the pronotum. Locate the head, and the antennae on the head. 3. The pronotum is a large, black dorsal shield with strong yellow or white markings. The markings are just coloration – they are not eyes. 4. Like most insects, the ladybug has three pairs of legs. On one leg, locate these parts: femur, tibia, tarsus. 5. The hardened, smooth outerwings (elytra) are typical of beetles (Order Coleoptera). The elytra are fused together in some beetles, which prevents flight. In ladybugs, the elytra are not fused. They can open, which exposes the soft underwings. 6. The coloration of the prontoum and outerwings can indicate species identity. For example, a common California species, Hippodamia convergens, has two yellowish marks on the protonum that converge to form an acute angle, as in Figure 6.5. Its outerwings are orange with a variable number of spots. Another species, Coccinella californica, has two widely separated spots on the pronotum, and usually no spots on its red outerwings.

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Activity: mackerel Phylum: Chordata Subphylum: Vertebrata Class: Osteichthyes Order: Perciformes Family: Scombridae Genus & species: Scomber japonicus (Pacific mackerel)

Figure 6.6. Fish anatomy. [From p. 280, 283, C.P. Hickman and L.B. Kats. 2004. Laboratory studies in integrated principles of zoology, 12th edition. McGraw Hill; New York.] Top: external anatomy. Bottom: internal anatomy.

1. Vertebrata is a subphylum characterized by a rigid endoskeleton. In some vertebrates, such as sharks and rays (cartilaginous fish), the endoskeleton is composed of cartilage. Most vertebrates have a calcium-based endoskeleton, such as the “bony” fish, 36

amphibians, reptiles, birds, and mammals. The “bony” fish (Class Osteichthyes) represent about 96% of all existing fish species. The mackerel is a “bony” fish. 2. On your mackerel, locate all of the external features labeled on Figure 6.6. Note that the mackerel has a nostril. This is used for olfaction (“smelling”), but not respiration. In general, fish respire by taking water into the mouth, passing it over the gills, extracting oxygen from the water, and then expelling the water. The water is expelled directly out of the body through the opening covered by the operculum. 3. Note that the mackerel has two adaptations for swimming very quickly. It has finlets, which are “barbs” on the tail that reduce turbulence as water passes over the body. The mackerel’s skin lacks scales, feeling very smooth to the touch. This “smooth skin” also reduces turbulence during swimming. Other fish of the Family Scombridae, such as various kinds of tuna, have finlets and lack scales. 4. Cut away the operculum from the mackerel’s left side, exposing the gills. Squeeze the mouth open to see how water flows from the mouth through the gills. BE CAREFUL OF THE TEETH. 5. BE SURE TO WORK ON A CUTTING SURFACE AND TO HAVE ABUNDANT PAPER TOWELS HANDY. Find the anus (the opening just before the anal fin). Starting at the anus, and being careful not to injure the internal organs, cut along the central line of the underbelly, towards the head. Cut past the pelvic fins. 6. Cut out a section of the mackerel’s left side. Starting at the anus, cut the body wall upwards, stopping near the lateral line. Then, starting at your cut at the pelvic fins, cut the body wall upwards, stopping near the lateral line. Then, remove the body wall by cutting between these two vertical cuts. You have now exposed the abdominal cavity. 7. Locate the following internal organs (refer to Figure 6.6): a. Intestine (labeled “duodenum” in Figure 6.6): usually encased in yellow fat; organ where final digestion occurs. b. Stomach: the anterior section of the intestine, which is usually dorsal to (above) the intestine; organ where food storage and break-down occur. c. Liver: dark organ between stomach and intestine; sends digested nutrients to bloodstream. d. Swim bladder: above the stomach; large organ that regulates buoyancy.

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Lab Report 6 1. For the animals that you examined, briefly describe at least three unique or distinctive features for each animal.

2. Compare and contrast the two animals. That is, describe features of their body design that are similar, and ways in which they differ.

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Lab 7: Human Anatomy Materials needed None Introduction The human body is organized into several organ systems, each with particular functions. System Integumentary Skeletal Muscular Nervous Endocrine Cardiovascular Lymphatic Respiratory Digestive Urinary Reproductive Male Female

Organs involved Skin; sweat & oil glands Bones Muscles Brain; nerves Glands Heart; vessels Lymph vessels; spleen Trachea; lungs Mouth; stomach; intestines Kidneys; urethra

Functions Protection; touch perception Protection & support of organs Manipulation & movement Sensory perception; cognition Regulate bodily processes Transport gas, nutrients, waste Recover fluid from blood; Exchange gas with environment Extract nutrients from food Remove nitrogenous waste

Testes; penis Ovaries; uterus; vagina

Produce sperm Produce egg; gestate embryo

In this laboratory, you will perform a self-examination to learn about three systems that are easy to visualize without dissection: skeletal, muscular, cardiovascular. This laboratory’s activity consists of filling out the lab report as you work. This laboratory is based on pp. 391-490 of the lab manual Mader (2001).

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Skeletal system There are 206 named bones in the human body, including the teeth. Like other vertebrates, the human skeleton has two components: axial and appendicular. The axial skeleton is the main vertical portion that includes the skull, vertebral column (a “chain” of individual vertebrae bones, protecting the spinal cord), ribs and sternum (“breastplate”). The appendicular skeleton consists of the bones of the appendages (arms and legs) and their supportive pectoral (shoulder) and pelvic (hip) girdles. The vertebrate skeleton has articulations, or joints. A joint is the meeting of two or more bones, connected by cartilage or another tissue.

Figure 7.1. Human skeleton. The axial skeleton is shown in pink; the appendicular skeleton is shown in tan. [From p. 180, S.S. Mader. 2004. Human biology laboratory manual, 8th edition. McGraw Hill; New York.]

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Muscular system The human body has about 700 named muscles. Humans have three kinds of muscles: smooth muscle (in walls of internal organs for involuntary movements), cardiac muscle (involuntary muscle of the heart), and skeletal muscle (voluntary movements of the skeleton). Skeletal muscles are often attached across a joint. The origin of the muscle is attached by a tendon to the stationary bone, and the insertion is attached by a tendon to the bone that moves. Muscles work in antagonistic pairs. Muscles either contract to move a bone, or relax to allow the opposing muscle to move the bone. Flexion is movement that decreases the angle of a joint; extension is movement that increases the angle of a joint. As an example, consider the muscles of your upper arm: the biceps and triceps. The origin of the biceps is attachment to the scapula (shoulder blade). The biceps extends over the front of the humerus to attach to the radius. The biceps is a flexor muscle – when it contracts, the forearm moves towards the upper arm. Regarding the triceps, its origin is attachment to the scapula (shoulder blade). The triceps extends over the rear of the humerus to attach to the ulna. The triceps is an extensor muscle – when it contracts, the forearm moves away from the upper arm.

Figure 7.2. Human muscles. Tendons are shown in gray/white. [From p. 331, E.N. Marieb. 2004. Human anatomy and physiology, 6th edition. Benjamin Cummings; San Francisco.]

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Cardiovascular system The cardiovascular, or circulatory, system consists of the heart and blood vessels. Powered by beatings of the heart, blood vessels receive oxygen from the lungs and nutrients from the liver. The vessels then deliver oxygen and nutrients to the cells of the body. In exchange, the blood vessels receive carbon dioxide and metabolic waste products from the cells. Carbon dioxide is delivered to the lungs for expulsion, and metabolic waste is delivered to the kidneys. Blood vessels are of two general kinds: arteries and veins. Arteries take blood away from the heart. Blood moving away from the heart usually contains oxygen. Veins take blood to the heart. Blood moving towards the heart usually lacks oxygen. Figure 7.3 shows major arteries.

Figure 7.3. Human arteries. [From p. 747, E.N. Marieb. 2004. Human anatomy and physiology, 6th edition. Benjamin Cummings; San Francisco.]

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Lab report 7 1. Using Figure 7.1, find each of the listed bones on your body. Then, using Figures 7.2 and 7.3, write in a muscle that attaches to the bone and an artery that runs alongside the bone. Bone

Muscle

Artery

Cranium Clavicle Sternum Humerus Radius or Ulna Coxal bone Metacarpals Femur Tibia Fibula Metatarsals

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