Class Test 7 (syllabus 5100)(marking Scheme)

Jurongville Secondary School Secondary 3 Express Biology Name: _________________________ (

)

Class: Sec 3___

Date: ____________

Class Test #6:

Transport in Mammals

Marks:

/ 20

Parent’s Signature: _____________

Duration: 30 minutes 5100 / 2

:

Section A (Short-Structured Questions)

Answer the following questions in the spaces provided. 1.

Fig 1.0 shows a section through a blood vessel. Fig 1.0

(a)

Name the type of blood vessel shown.

[1]

Vein (b)

Give two reasons to justify your answer to (a).

[2]

Presence of valve; Thin wall and large lumen. (c)

The type of blood vessel shown in Fig 1.0 carries oxygenated blood. State the specific name of this blood vessel and briefly state its function [2] Pulmonary vein; Transport oxygenated blood from lungs to the heart. [Total: 5]

1

2.

Fig. 1.1 shows a diagram of a human heart.

X

Fig 1.1 (d) Left Ventricle [1] Correct area shaded [1]

(a)

Name structure X.

[1]

Septum. (b) Briefly describe the importance of structure X.

[2]

Prevents mixing of oxygenated blood with deoxygenated blood; Ensures all oxygenated blood is sent to all parts of the body; Ensures all deoxygenated blood is sent to the lungs. Any 2 of the above. (c) Suggest the implication of a hole existing at X at the location labeled in Fig 1.1. [3] Ref to Left Ventricle: Oxygenated blood in LV will be mixed with deoxygenated blood from RV; Lower concentration of oxygen carried in blood inside LV compared to normal case; Non-fully oxygenated blood does not contain enough oxygen to be distributed to body cells in systemic circulation. (d) Shade and name the regions with the thickest wall. Justify your answer.

[3]

Reject if shaded area overlaps with region of RV. Justification: Enables LV’s muscular walls to pump blood more forcefully with higher pressure to all body cells in systemic circulation.

2

[Total: 9]

3.

Compare the differences in the structures and blood flow inside the three named types of blood vessels you have studied. [6] Blood vessel [1] Wall [1] and Lumen size [1]

Artery Wall is thick, muscular and elastic, relatively small lumen

Capillary Wall is one-cell thick, lumen size of a RBC

Valves [1]

Absent

Absent

Blood flow [2]

1. Blood moves along by contraction of the muscles of its walls.

1. Blood flows smoothly 2. Pressure at arteriole end > pressure at venule end.

2. Blood flows under great pressure, fast, in spurts.

Vein Wall is thin, less muscular and elastic, lumen size large relatively Semi-lunar valves to prevent backflow of blood 1. Blood flows smoothly and slowly 2. Blood moves along vein by contractions of the body muscles on the vein [Total: 6]

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