circulatory system

Question 1

name the 5 types of blood vessels

Answer 1

artery, arterioles, veins, venules, and capillaries

Question 2

Arteries structure and function

Answer 2

Arteries pump blood away from the heart, either to the lungs or the body. Thick, elastic, and muscular to allow for blood to be moved forcefully and to accommodate for high pressure.

Question 3

Arterioles structure and function

Answer 3

Arterioles are small arteries that branch off arteries, they provide 80% of the body’s blood flow resistance and distribute blood to capillary beds. They also have muscular walls but are thinner than arteries.

Question 4

Veins structure and function

Answer 4

Veins pump blood back into the heart from either the lungs or the body. They are thinner and less muscular-walled than arteries because the pressure is much lower. due to the movement of blood against gravity. Some (particularly in the leg) contain valves to stop blood from flowing backwards.

Question 5

venule structure and function

Answer 5

venules are smaller veins that join together off capillary beds and eventually form a vein. Venules have thinner walls than arterioles.

Question 6

capillaries

Answer 6

The role of capillaries is to allow for gaseous exchange to occur between the blood and body cells. The structure of capillaries accommodates this because the walls of the capillaries are only one cell thick, allowing oxygen and co2 to move between the cell and the blood.

Question 7

Diffusion

Answer 7

The process of oxygen and co2 moving between the capillaries and body cells. It is the process of a high concentration of oxygen in the blood moving to a low concentration of oxygen in the cells (or vise versa).

Question 8

Why does the speed of blood flow slow down in the capillary.

Answer 8

Blood flow slows down in the capillary because the diameter of the vessel decreases, causing resistance to increase, therefore causing blood to move slower. This allows for diffusion to occur.

Question 9

where does gaseous exchange occur

Answer 9

Between capillaries and body cells as well as between capillaries and alveoli

Question 10

What are the 4 components of blood

Answer 10

plasma, white blood cells, red blood cells, and platelets

Question 11

Plasma

Answer 11

Plasma is the liquid portion of blood that carries cells, nutrients, and waste products (i.e the other blood components)

Question 12

White Blood Cells (WBC)

Answer 12

WBC are part of the body’s immune system. they fight off bacteria and viruses. They are made in bone marrow

Question 13

Red Blood Cells (RBC)

Answer 13

RBC are responsible for delivering oxygen to the body and getting rid of co2. They contain a protein called haemoglobin which holds nutrients and waste products.

Question 14

platelets

Answer 14

Platelets are cell fragments that assist the formation of blood clots to stop bleeding.

Question 15

describe systemic circulation

Answer 15

Systemic circulation is the circulation of blood between the heart and the body. Oxygenated blood enters the heart through the pulmonary vein, It moves through the left atrium and into the left ventricle. Blood is then pumped out of the left ventricle through the aorta. Oxygen is delivered to body cells through capillaries and co2 is taken out of the cells into the blood. The deoxygenated (DO) blood is then transported back to the heart via veins and enters the heart through the superior and inferior vena cava.

Question 16

describe pulmonary circulation

Answer 16

Pulmonary circulation is the circulation of blood between the heart and the lungs. DO blood enters the heart and into the right atrium. The blood flows through the right atrium into the right ventricle and is then pumped out of the heart to the lungs via the pulmonary artery. Once the DO blood reaches the lungs, co2 moves out of the blood and oxygen moves into the blood through a process of diffusion. Once this is completed, the oxygenated blood moves back into the heart through the pulmonary vein.

Question 17

what is the heart’s immediate response to exercise?

Answer 17

Exercise requires the muscles to work hard to exert the force needed for movement. This results in a large output of Carbon Dioxide and increased demand for oxygen to be delivered to the muscles. Cardiac output (volume of blood being pumped per minute) and heart rate (total heartbeats per minute) increase so efficiency is increased. Blood pressure also increases because there is more blood moving through the vessels - the higher the pressure, the faster blood will flow. This all occurs so that oxygen can be delivered to the muscles more efficiently and CO2 can be taken out more efficiently. Blood flow is also redirected as a response to exercise. Increased blood flow to working muscles.