Cardiac System

Question 1

Functions of the cardiovascular system (6)

Answer 1

1. Transport of O2, nutrients, CO2, waste, etc
2. Maintains blood flow and varies the rate of flow according to the energy needs of cells
3. Homeostasis of fluid level
4. Homeostasis of pH
5. Homeostasis of temperature
6. Defense against microorganisms

Question 2

Functions/characteristics of the pericardium (3)

Answer 2

1. Serous membrane; means ‘around the heart’
2. Holds heart in place
3. Protects heart from friction and over-expansion

Question 3

Functions/characteristics of the myocardium (6)

Answer 3

1. Muscular wall of the heart
2. Powerful, thick, tireless
3. Cardiac muscle
4. 2 sets of muscles; atria and ventricles contract independently
5. Swirled layers of muscle so contraction squeezes chambers to empty them
6. Autonomic

Question 4

Functions/characteristics of the epicardium (3)

Answer 4

1. Inner lining
2. Perfectly smooth to prevent coagulation of the blood
3. Endothelium

Question 5

Structural characteristics of cardiac muscle tissue (7)

Answer 5

1. Involuntary
2. Striated
3. Bifricated fibers
4. Intercalated discs
5. One nucleus/fiber
6. Many mitochondria
7. Only found in the myocardium

Question 6

Functional characteristics of cardiac muscle tissue (4)

Answer 6

1. All or Nothing Law; no graded response
2. Autonomic
3. Does not fatigue
4. Does not exhibit tone