Insulation Support

 Cells: smallest structural unit of living things  Cells: some are flat, brick shaped, thread-like, irregular… all different shapes & sizes  Parts of cell:  Plasma membrane: Membrane that encloses the cytoplasm and forms the outer boundary of the cell… keeps the cell whole and intact… only allows certain fluids inside the cell…  Cytoplasm: The internal living material of cells… lies between plasma membrane and nucleus… small structures that make up the cytoplasm are organelles.. •

Organelles  Ribosomes: “protein factories”  Endoplasmic reticulum: Network of tubules and vesicles… rough ER receives and transports newly made proteins… smooth ER makes new membrane…  Golgi apparatus: “chemical processing and packaging center”  Mitochondria: “power plants”… the survival of cells depends on mitochondrial chemical reactions… each mitochondrion has its own DNA molecule…  Lysosomes: “digestive bags”… contain enzymes that can digest food compounds… help protect cells against destruction by microbes…  Centrioles: Paired organelles… rod-shaped… play an important role in cell division…  Cilia: Extremely fine, almost hairlike, extensions on the exposed or free surfaces of some cells… ex. By moving as a group upward they propel mucus upward over the cells that line the respiratory tract…  Flagella: In a human the only flagellum is the tail of the sperm, which makes it possible for the sperm to “swim”

 Nucleus: Controls every organelle in the cytoplasm and the process of cell reproduction… surrounded by the nuclear envelope which is made up of the nucleoplasm (which contains the nucleolus and chromatin granules)… •

Nucleolus: Critical in protein formation b/c it programs the formation of ribosomes…

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Chromatin granules: Threadlike structures made of proteins and DNA

 Functions: passive transport, active transport …  Active transport: energy is obtained from ATP, which is produced in the mitochondria… ATP breaks down for energy to be used… examples are phagocytosis, pinocytosis, and ion pumps… •

Phagocytosis: ingestion and digestion of particles by a cell…

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Pinocytosis: mechanism used to transfer fluids or dissolved substances into cells…

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Ion pumps: uses energy from ATP to actively move ions across cell membranes against their concentration gradients…

 Passive transport: primary processes are diffusion and filtration. •

Diffusion: substances scatter themselves evenly throughout an available space… examples are osmosis and dialysis…  Osmosis: movement of a fluid through a semipermeable membrane…

The section on A&P is 25% of Part 1 of the exam… Don’t  Dialysis: separation of smaller particles from larger focus all of your attention here!! particles through a semipermeable membrane… •

Filtration: movement of water and solutes through a membrane b/c of greater pushing force one side of the membrane than the other side (called hydrostatic pressure)… ex. Process responsible for urine formation in the kidney (wastes are filtered out of the blood into the kidney tubules)

 Cells that reproduce do so by mitosis (a cell divides to multiply)

 Tissues: groups of similar cells  Four main kinds of tissues:  Epithelial: covers the body and many of its parts… contain no blood vessels… divided by shape and arrangement of cells… •

Shape  Squamous: flat and scalelike  Cuboidal: cube shaped  Columnar: higher than they are wide

 Transitional: varying shapes that can stretch •

Arrangement  Simple: single layer of cells of the same shape  Stratified: many layers of cells

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Examples  Simple squamous: alveoli of lungs… lining of blood…  Stratified squamous: surface of skin…  Simple columnar: surface layer of lining of stomach…  Stratified transitional: urinary bladder…  Pseudostratified: surface of lining of trachea…  Simple cuboidal: glands, kidney tubules…

 Connective: most abundant and widely distributed tissue in body; has numerous functions… 7 major types… •

Areolar: loose arrangement of fibers and cells… between other tissues and organs… function is connection…

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Adipose or fat: cells contain large fat compartments… area under skin/padding at various points… function is protection/insulation, support, nutrient reserve…

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Fibrous: dense arrangement of collagen fiber bundles… tendons, ligaments, fascia, scar tissue… function is flexible but strong connection…

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Bone: hard, calcified matrix arranged in osteons… skeleton… function is support and protection…

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Cartilage: hard but flexible matrix with imbedded chondrocytes… part of nasal septum, surfaces of bones, larynx, rings in trachea… function is firm but flexible support…

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Blood: liquid matrix with flowing red & white cells… blood vessels… function is transportation…

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Hematopoietic: liquid matrix with dense arrangement of blood cell-producing cells.. red bone marrow… function is blood cell formation…

 Muscle: movement specialists of the body… higher degree of contractility than any other tissues… 3 kinds…

 Skeletal: (striated voluntary): long, threadlike cells with multiple nuclei and striations… muscle that attach to bones… function is maintenance of posture, movement of bones…  Cardiac: (striated involuntary): branching, interconnected cylinders with faint striations… wall of heart… function is contraction of the heart…  Smooth: (nonstriated involuntary or visceral): threadlike cells with single nuclei and no striations… walls of blood vessels, ducts of glands…  Nervous: consists of neurons and glia that provide rapid communication and control of body function… brain, spinal cord, nerves… function is irritability, conduction…