Circulation

Question 1

What are the two challenges?

Answer 1

1. Deliver O2 to mitochondria for ATP production
2. Return CO2 and remove from organism

Question 2

ventilation?

Answer 2

Ventilation → Diffusion is in the respiratory system

Question 3

Diffusion?

Answer 3

Diffusion → Circulation is in the circulatory system

Question 4

Ventilation in the ____ → Diffusion of air or water into ____ in the blood → Diffusion to the ____ resulting in ______

Answer 4

environment
circulation
mitochondria
cellular respiration

Question 5

Circulatory Systems 3 of them

Answer 5

No circulatory system
Open circulatory system
Closed circulatory system

Question 6

No circulatory system and example:

Answer 6

• simple invertebrates - diffusion only and passive movement

ex: marine invertebrates: sponges etc.

Question 7

Open circulatory system and name advantage and disadvantage

Answer 7

• Most invertebrates - Hemolymph because all liquid is mixed
• Advantages: don”t have to have vessels that goes to every single organ
• Disadvantage: less effective if you had a dedicated system. More mixing of fluids that happen

Question 8

-Closed circulatory system:

Answer 8

• vertebrates

Question 9

What does the open circulatory system assure?

Answer 9

• assures constant motion and directional distribution
• but is essentially one open cavity

Question 10

The closed circulatory system process

Answer 10

• heart pumps blood through closed tubular vessel
• branches and becomes thinner
• capillaries allow gas exchange
• Blood from heart is transported by arteries, blood is returned to heart by veins

Question 11

The fish circulatory system has:

Answer 11

1 circuit and 2 chambers

Question 12

The closed circulatory system has ___ separate systems… IN FISH BTW

The heart has 2 what? And name the parts and how blood moves around

Answer 12

• Has two separate systems
  
  1. Exhcange with tissues
  2. exchange with environment (respiartory surface: gills or lung)
• Heart has 2 chambers
  
  • Atrium - blood enters here in the heart
  • Ventricle - contracts and pushes blood towards the gill. Oxygen is taken up in the gills

Question 13

Vertebrate circulatory system has evolved:

Answer 13

Amphibians/turtles, snakes, lizards: 2 circuits 3-chambered heart

Crocodiles and birds: 2 circuits and 4-chambered heart

Mammals: 2 circuits and 4-chambered heart but ventricle divided

Question 14

Mammals: 2 circuits are…

Answer 14

Pulmonary circuit:

1. Blood enters right atrium on return from body
2. Blood enters right ventricle
3. Blood is pumped to lungs from right ventricle

Systemic circuit:

1. Blood returns to left atrium from lungs
2. Blood enters left ventricle
3. Blood is pumped to body from left ventricle

Question 15

Partial pressure of oxygen and carbon dioxide 9 steps…

Answer 15

1. Inhaled air
2. Alveolar space (in lungs)
3. Blood leaving alveolar capillaries
4. Blood entering tissue capillaries
5. Tissues
6. Blood leaving tissue capillaries
7. Blood entering alveolar capillaries
8. Alveolar space (in lungs)
9. Exhaled air

Question 16

What has to be synchronized?

Answer 16

• The contraction of the different chambers must be synchronized. Locally regulated; modulated by chemical signals

Question 17

How is it synchronized?

Answer 17

• contraction is initiated in pacemaker cells
• located in the sinoatrial node (SA node)
• signal spreads along the muscle via gap junctions

Question 18

Steps of the signals through the heart

Answer 18

1. Signal originates at SA node
2. Signal spreads over atria; atria contract
3. Signal is delayed at AV node
4. Signal spreads
5. Ventricles relax

Question 19

How can we measure this the spread of the electrical signal?

Answer 19

• Electrocardiogram (ECG)

Question 20

Cardiac Cycle?

Answer 20

Ventricular diastole
Ventricular systole

Question 21

Ventricle Systole

Answer 21

-Both ventricles contract simultaneously

Question 22

Ventricle diastole:

Answer 22

• Both ventricles relax simultaneously: