Transport in mammals

Question 1

What is the primary function of the circulatory system in mammals?

Answer 1

transport nutrients, gases, hormones, and waste products throughout the body, and to maintain homeostasis by regulating temperature and pH.

Question 2

What are the main components of mammalian blood?

Answer 2

• RBC
• WBC
• Platelets
• Plasma

Question 3

Structure of RBC

Answer 3

Red blood cells are biconcave, disk-shaped cells without a nucleus.

Question 4

Function of RBC

Answer 4

To transport oxygen from the lungs to the tissues and carbon dioxide from the tissues to the lungs.

Question 5

What is the role of white blood cells?

Answer 5

To defend the body against infection and foreign invaders.

Question 6

What is the role of platelets in the circulatory system?

Answer 6

To aid in blood clotting and prevent excessive bleeding.

Question 7

What is plasma?

Answer 7

The liquid component of blood, which transports nutrients, hormones, and waste products.

Maintains blood pressure and volume

Question 8

Explain the double circulatory system in mammals.

Answer 8

Pulmonary circulation (between the heart and lungs) and systemic circulation (between the heart and the rest of the body).

Question 9

Arteries

Answer 9

Thick, muscular walls, narrow lumen, carry oxygenated blood away from the heart under high pressure.

Question 10

Veins

Answer 10

Thinner walls, larger lumen, contain valves to prevent backflow, carry deoxygenated blood towards the heart under low pressure.

Question 11

Capillaries

Answer 11

Very thin walls (one cell thick), narrow lumen, facilitate exchange of gases, nutrients, and waste between blood and tissues

Question 12

Explain the cardiac cycle.

Answer 12

The sequence of events in one heartbeat, including :- - atrial systole,
- ventricular systole
- diastole.

Question 13

What is systole?

Answer 13

The contraction phase of the heart chambers, pushing blood out of the heart.

Question 14

What is diastole?

Answer 14

The relaxation phase of the heart chambers, allowing them to fill with blood.

Question 15

What are the four chambers of the human heart?

Answer 15

• right atrium
• right ventricle
• left atrium
• left ventricle

Question 16

Blood pathway

Answer 16

Vena cava → Right atrium → Tricuspid valve → Right ventricle → Pulmonary valve → Pulmonary artery → Lungs → Pulmonary veins → Left atrium → Mitral valve → Left ventricle → Aortic valve → Aorta → Body.

Question 17

What is the role of the heart valves?

Answer 17

To prevent backflow of blood and ensure unidirectional flow through the heart.

Question 18

Which nervous system components regulate heart rate?

Answer 18

The autonomic nervous system regulates heart rate through the sympathetic (increases heart rate) and parasympathetic (decreases heart rate) nervous systems.

Question 19

What is the role of the lymphatic system in transport?

Answer 19

To return excess tissue fluid to the bloodstream and provide immune functions.

Question 20

How do nutrients get transported from the digestive system to the rest of the body?

Answer 20

Via the blood, after being absorbed into the capillaries in the intestines and transported to the liver via the hepatic portal vein.

Question 21

4 main valves

Answer 21

• Tricuspid
• Pulmonary
• Bicuspid ( Mitral )
• Aortic

Question 22

Tricuspid valve

Answer 22

between right atrium and right ventricle.

Question 23

Pulmonary valve

Answer 23

between right ventricle and pulmonary artery.

Question 24

Bicuspid valve ( Mitral )

Answer 24

between left atrium and left ventricle.

Question 25

Aortic valve

Answer 25

between left ventricle and aorta.

Question 26

What is the function of the coronary arteries?

Answer 26

The coronary arteries supply oxygenated blood to the heart muscle (myocardium).