LECTURE 5: heart anatomy part 2

Question 1

atrioventricular valves function is to…

Answer 1

prevent blood returning to aria during ventricular contraction

Question 2

AV valve on right side

Answer 2

tricuspid valve

Question 3

AV valve on left side

Answer 3

bicuspid valve

Question 4

AV valves are …. during diastole?

Answer 4

open

Question 5

AV valves are …. during systole?

Answer 5

closed

Question 6

semilunar valves function is to…

Answer 6

Prevent blood returning to ventricles during filling (diastole).

Question 7

SL valves on right side

Answer 7

Pulmonary (semilunar) valve, 3 cusps.

Question 8

SL valves on left side…

Answer 8

Aortic (semilunar) valve, 3 cusps

Question 9

describe the opening and closing of SL valves in relation to blood flow

Answer 9

Pushed open as blood flows out of heart. Close as blood starts to back flow

Question 10

SL valves are …. during diastole?

Answer 10

shut

Question 11

SL valves are …. during systole?

Answer 11

open

Question 12

papillary muscles

Answer 12

finger like projections of ventricular wall, tip of papillary muscle has chords attached to end of muscle that are attached to free end of AV valve leaflets

Question 13

4 major arteries in heart

Answer 13

1. right coronary artery
2. left coronary artery
3. anterior interventricular artery
4. circumflex artery

Question 14

3 major veins in heart

Answer 14

1. coronary sinus
2. great cardiac vein
3. small cardiac vein

Question 15

RHS is drained by…

Answer 15

small cardiac vein

Question 16

LHS is drained by…

Answer 16

great cardiac vein

Question 17

myocardium function

Answer 17

beating of heart

Question 18

myocardium features

Answer 18

Features of both smooth and skeletal muscle as well as cardiac muscle specific specialisations

Question 19

cardiac muscle cell structure

Answer 19

• Striated
• Short, branched cells
• One or occasionally 2 nuclei/cell
• Central (oval shaped), nucleus
• Cytoplasmic organelles packed at the poles of nucleus

Question 20

how are cardiac muscle cells interconnected?

Answer 20

Interconnected with neighbouring cells via intercalated disks (ICD’s)

Question 21

intercalated disks

Answer 21

• Boundary between 2 cells

- Intercalated discs = region between cardio myocytes

Question 22

3 junction types

Answer 22

1. adhesion belt
2. desmosomes
3. gap junctions

Question 23

adhesion belts as a junction

Answer 23

linking actin to actin -vertical portion (transfers force)

Question 24

desmosomes as a junction

Answer 24

linking cytokeratin with cytokeratin

buttons cells together keeping them fused

Question 25

gap junctions as a junction

Answer 25

electrochemical communication- horizontal portion

Question 26

purkinje cells are

Answer 26

Bloated’ non-contractile cardiac muscle involved with electrical conduction

Question 27

autonomic nerves alter the rate of…

Answer 27

conduction impulse generation

Question 28

the conduction system is responsible for

Answer 28

the co-ordination of heart contraction and of atrioventricular valve action

Question 29

features of purkinje cells

Answer 29

• (some) Peripheral myofibrils.
• Central nucleus
• Mitochondria
• Glycogen
• Lots of gap junctions
• Some desmosomes & few adhesion belts
• 1% of cardiac cells

Question 30

cardiac muscle vs. skeletal muscle

Answer 30

Nuclei, branched striations, cell shape, mitochondria, intercalated disks