Unit 4: Cardiovascular Circulation

Question 1

True or false: Muscle contraction requires ATP.

Answer 1

True

Question 2

What are the 4 ways ATP is used/made by the body in order to run?

Answer 2

1. Use the ATP available in muscle cells.
2. Synthesize more ATP using phosphocreatine.
3. Synthesize more ATP using glycolysis.
4. Synthesize more ATP using oxidative metabolism.

Question 3

How long do the reserves of ATP in muscles last?

Answer 3

1-3 seconds.

Question 4

How long does the ATP synthesized using phosphocreatine last?

Answer 4

8-10 seconds.

Question 5

True or false: The phosphocreatine reaction producing ATP is slow.

Answer 5

False. It is actually very fast. 4 mols ATP are made every minute.

Question 6

What is the name of the system that includes the ATP in the muscle cells and the synthesis of ATP using phosphocreatine called?

Answer 6

The phosphagen system.

Question 7

At what rate is ATP synthesized using glycolysis? How long will this source of energy last?

Answer 7

2.5 mols ATP per minute. It lasts from 1.3 to 1.6 minutes.

Question 8

Does glycolysis require oxygen?

Answer 8

No. This is an anaerobic reaction.

Question 9

How does glycolysis work?

Answer 9

Glycogen is broken down into glucose. Glucose is then used in reaction.

Question 10

What is another name for “synthesis of ATP by glycolysis”?

Answer 10

Lactic acid fermentation (if there is insufficient oxygen and the pyruvates are converted into lactic acid).

Question 11

How does the oxidative system make ATP?

Answer 11

It requires oxygen. Pyruvates are also used in many reactions.

Question 12

What reactions are used in the oxidative system?

Answer 12

Citric acid cycle, electron transport, chemiosmosis.

Question 13

At what rate is ATP synthesized by the oxidative system? How long will this source last?

Answer 13

1 mol ATP per minute. Infinite duration since this is considered to have an unlimited supply (so long as food and oxygen are available).

Question 14

What nutrients are absorbed by the small intestine?

Answer 14

1. Monoglycerides
2. long fatty acids
3. monosaccharides
4. amino acids
5. short fatty acids

Question 15

What goes on when monoglycerides and long fatty acids are absorbed?

Answer 15

They are modified and form chylomicrons.

Question 16

Where do chylomicrons go?

Answer 16

Enters lacteal lymphatic system and are transported throughout the body.

Question 17

What happens to monosaccharides, amino acids and short fatty acids when they are absorbed by the small intestines?

Answer 17

They enter the capillaries of the circulatory system. The capillaries are fenestrated in the intestines.

Question 18

What are the 3 types of capillaries?

Answer 18

Fenestrated, continuous and sinusoid.

Question 19

In the circulation of nutrients in the body, where do they go to after being absorbed by the stomach, small intestine and the large intestine?

Answer 19

They do to the liver. Capillaries in these organs empty into the hepatic portal vein.

Question 20

What happens once the nutrients get to the liver?

Answer 20

The liver picks up some nutrients thru sinusoid capillaries.

Question 21

After going to the liver, where do the remaining nutrients go?

Answer 21

They are sent to the heart.

Question 22

What changes are undergone in the liver?

Answer 22

The liver converts glucose into glycoproteins, it uses amino acids and triglycerides are transformed into lipoproteins.

Question 23

What pathway does the blood coming from the liver take?

Answer 23

• Into the right atrium
• Right atrium contracts and blood flows to the right ventricle
• Blood goes to the lungs (picks up oxygen Hb=80%)
• Blood goes to the left atrium

Question 24

How is the heart beat coordinated?

Answer 24

• Signal is initiated by the SA node in the right atrium, causing both atria to depolarize and contract.
• Signal reaches the AV node causing both ventricles to depolarize and contract.

Question 25

What is the systole in blood pressure measurements?

Answer 25

The top number.

Question 26

What is the diastole in blood pressure measurements?

Answer 26

The bottom number.

Question 27

How are nutrients and oxygen delivered throughout the body?

Answer 27

Through capillaries.

Question 28

True or false: The movement of blood is very fast through capillaries.

Answer 28

False, it is very slow. This maximises time for substance exchange.

Question 29

What is the pressure like in capillaries?

Answer 29

Higher on the arterial end (allows nutrients to exit).

Lower on the vein end (allows debris to enter).