The liver and homeostatis

Question 1

How many lobes does the liver have?

Answer 1

4 lobes, all of unequal sizes and is located just below the diaphragm

Question 2

Name some examples of how the liver contributes to homeostatis.

Answer 2

1. Storage- Glycogen,Fat,Iron
2. Regulation,synthesis and secretion- Bile, Makes plasma proteins, produces cholestrol,makes urea,produces heat
3. Breaks down aged blood cells,produces hormones, processes digested food from the intestine, neutralises and destroys drugs and toxins.
4. Fights infections- Marcophages destroys bacteria (Kupffer)

Question 3

What are sinusoids?

Answer 3

Very wide thin-walled blood vessels lined with endothelial cells and Kupffer cells (macrophages) which remove aged red blood cells,bacteria and debris from the blood.

Question 4

What tissue are the liver lobule surrounded by?

Answer 4

connective tissue

Question 5

What are the purpose of Stellate cells?

Answer 5

They are involved in fibrosis and the formation of scar tissue in response to liver damage.

Question 6

What are the three vessels which cluster called the portal triad found around the edge of each lobule?

Answer 6

1. Branch of hepatic portal vein
2. Branch of hepatic artery
3. Bile duct

Question 7

What are the functions of bile?

Answer 7

1. Breaking down fat molecules

2. Removal of waste products

Question 8

The liver converts glucose and stores it as..

Answer 8

Glycogen

Question 9

What does bile salts in the liver help to digest?

Answer 9

Fatty foods

Question 10

Bile salts act like…

Answer 10

detergents

Question 11

Where is bile released?

Answer 11

In the small intestine

Question 12

Excess amino acids are broken down in the liver to to form….

Answer 12

urea

Question 13

Name the functions of the liver.

Answer 13

1. Digestion
2. Metabolism
3. Combating infection
4. Blood composition
5. Elimination of waste

Question 14

How is urea eliminated from the body?

Answer 14

1. The liver breaks down amino acids into ammonia,co2,water and energy.
2. Ammonia is toxic to cells and the liver converts it to urea.
3. Urea is then transported in the blood to the kidneys, where it is eliminated In urine.

Question 15

What happens during carbohydrate metabolism in the liver.

Answer 15

1. Glycogenesis- stores excess glucose
2. Glucogenolysis- glycogen is broken down to release glucose.
3. Gluconeogensis- New glucose is formed from protein and glycerol (from fat).

Question 16

What happens during protein metabolism in the liver.

Answer 16

The removal of an amino group from an amino acid occurs and urea formation.
Transamination also occurs. (amino acids are converted into other amino acids that the body needs)

Question 17

What happens during fat metabolism in the liver.

Answer 17

This produces triglycerides,cholestral and lipo proteins.

Triglycerides are converted to fatty acids and glycerol when energy is needed.

Question 18

Where is the liver located?

Answer 18

It is located in the right upper quadrant of the abdomen, beneath the diaphragm.

Question 19

Where is bile stored?

Answer 19

Gall bladder

Question 20

Where is bile released?

Answer 20

Bile is released in the duodenum.

Question 21

What makes up bile?

Answer 21

Water
Mineral salts
Mucus
Bile salts
Bile pigments 
Cholesterol
Recithin

Question 22

What is the role of bile salts?

Answer 22

To breakdown fat globules into tiny, microscopic droplets.
Bile salts are then reabsorbed in the ileum and passed back into the bloodstream.
Further, they are involved in the transport and absorption of fat soluble vitamins.