Lecture 7 AI generated

Question 1

Describe the structure of the heart in terms of its pumps and chambers.

Answer 1

The heart has two pumps - the left heart (LA, LV) and the right heart (RA, RV), each with 4 chambers.

Question 2

Explain the two circuits that make up the cardiovascular system.

Answer 2

The cardiovascular system consists of the pulmonary circuit and the systemic circuit.

Question 3

Define the layers of muscle that make up the heart.

Answer 3

The heart consists of three layers of muscle: endocardium, myocardium, and epicardium.

Question 4

How do action potentials travel through the heart from the SA node to the ventricles?

Answer 4

Action potentials travel through the atria from the SA node to the AV node, then to the bundle of His and Purkinje fibers.

Question 5

Describe the function of arteries, micro-circulation, and veins in the cardiovascular system.

Answer 5

Arteries distribute substances, micro-circulation is for diffusion and filtration, and veins collect substances.

Question 6

Explain the significance of the increase in the number of vessels at the capillary level.

Answer 6

The increase in vessels at the capillary level allows for a larger surface area, slower speed, and more options for substance transfer.

Question 7

What are the functional consequences of the increase in the number of vessels at the capillary level?

Answer 7

The functional consequences include a larger surface area, slower speed allowing more time for transfer, and increased options for substance exchange.

Question 8

Describe the primary function of.

Answer 8

Blood serves as a distribution system for gases and nutrients for energy production.

Question 9

Define erythropoiesis.

Answer 9

Erythropoiesis is the process of red blood cell production in the bone marrow.

Question 10

How are platelets primarily utilized in the body?

Answer 10

Platelets are mainly used for blood clotting.

Question 11

Do red blood cells have a nucleus?

Answer 11

No, red blood cells do not have a nucleus.

Question 12

Describe the composition of plasma in blood.

Answer 12

Plasma is the extracellular fluid rich in proteins.

Question 13

What is the lifespan of red blood cells?

Answer 13

Red blood cells have a lifespan of 120 days.

Question 14

Define serum in the context of blood.

Answer 14

Serum is the residual fluid after clotting, containing plasma minus clotting factors and fibrinogen.

Question 15

How is ATP exclusively used in red blood cells?

Answer 15

ATP is exclusively used by glycolysis in red blood cells due to the absence of mitochondria.

Question 16

Describe the main tasks of blood cells.

Answer 16

Carrying O2 from the lungs to the systemic tissues, carrying O2 from the tissues to the lungs, and assisting in the buffering of acids and bases.

Question 17

What is the role of mitochondria in red blood cells and why are they removed?

Answer 17

Mitochondria are removed because they might use the oxygen. They are not needed for the main function of red blood cells.

Question 18

Define Bohr effect in the context of oxygen transport.

Answer 18

Bohr effect refers to the phenomenon where hemoglobin releases oxygen more readily in tissues with high pCO2 and low pH, facilitating oxygen delivery.

Question 19

How does iron in heme contribute to oxygen binding in hemoglobin?

Answer 19

Iron in heme can bind oxygen as it easily shifts between Fe 2+ and Fe 3+. This binding changes the confirmation of hemoglobin, increasing its affinity for more oxygen.

Question 20

Explain the significance of blood pressure in cardiovascular health.

Answer 20

High blood pressure is a leading risk factor for mortality. Blood pressure refers to the pressure of circulating blood against the walls of blood vessels, usually expressed as systolic over diastolic pressure.

Question 21

Describe how blood pressure is measured and where it is highest in the body.

Answer 21

Blood pressure is measured in millimetres of mercury (mmHg) above atmospheric pressure. It is highest in the left ventricle and large arteries due to their proximity to the heart.

Question 22

What is the mean arterial pressure (MAP) and how is it calculated?

Answer 22

The mean arterial pressure is the average blood pressure over a cardiac cycle. It is calculated as MAP = CO * SVR, where CO is cardiac output and SVR is systemic vascular resistance.

Question 23

How do baroreceptors and the autonomic nervous system respond to changes in blood pressure?

Answer 23

Baroreceptors in the arteries sense blood pressure changes and signal the autonomic nervous system. Low blood pressure leads to increased firing, activating the sympathetic system to increase heart rate, stroke volume, vasoconstriction, and cardiac contractility.

Question 24

Define the role of the RAAS system in regulating blood pressure.

Answer 24

The RAAS system is involved in the hormonal regulation of blood pressure. It responds to changes in blood pressure by releasing hormones that help maintain fluid balance and blood volume.

Question 25

Describe the functions of the kidney in relation to blood pressure regulation.

Answer 25

The kidney filters plasma, excretes waste, maintains water balance, and secretes hormones involved in blood pressure regulation. The nephron is the functional unit of the kidney, regulating blood pressure through processes like filtration and hormone secretion.

Question 26

Describe the process of water uptake regulation in the kidney.

Answer 26

Water uptake in the kidney is regulated by the antidiuretic hormone (ADH), which determines the permeability to water of the collecting duct.

Question 27

What is the role of Renin-Angiotensin-Aldosterone-System (RAAS) in the kidney?

Answer 27

RAAS triggers responses in the kidney for low blood pressure, regulating blood pressure and sodium levels.

Question 28

How does chronically high salt intake affect kidney function and blood pressure?

Answer 28

High salt intake can lead to reduced kidney function, causing increased salt reabsorption, water retention, and ultimately hypertension.

Question 29

Define the impact of mutations on blood pressure regulation in the kidney.

Answer 29

Mutations affecting genes involved in renal sodium handling can alter blood pressure regulation.

Question 30

What percentage of the body’s oxygen consumption is consumed by the kidneys?

Answer 30

The kidneys consume 6% of the body’s oxygen consumption, the highest per mass in the body.