5.3 Liver Flashcards Preview

Biology Chapter 16 (AQA) > 5.3 Liver > Flashcards

Flashcards in 5.3 Liver Deck (55)
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1
Q

What are the 3 main metabolic waste products in animals?

A

Carbon dioxide
Bile pigments
Nitrogenous waste

2
Q

What is CO2 a waste product of?

A

Respiration it is excreted from lungs

3
Q

What are bile products a waste product of?

A

Haemoglobin breakdown they are excreted in bile from the small intestine via the gall bladder and bile duct

4
Q

What is nitrogenous waste/urea a waste product of?

A

The breakdown of amino acids in the liver excreted by kidneys into the urine

5
Q

How much of the total body mass does the liver make up?

A

5%

6
Q

What can the liver do if damaged/ part removed?

A

Regenerate and grow quickly

7
Q

The liver has a rich blood supply of what per minute?

A

1 dm3

8
Q

Which artery supplies the liver with blood?

A

The hepatic artery

9
Q

Which vein removes blood from the liver and returns it to the heart?

A

The hepatic vein

10
Q

What does the hepatic portal vein do?

A

Carries blood containing digestive products from intestines to liver

11
Q

Up to 75% of blood flowing through the liver comes from where?

A

The hepatic portal vein

12
Q

What are liver cells called?

A

Hepatocytes

13
Q

What organelles indicate hepatocytes are metabolically active?

A

Large nuclei
Prominent Golgi apparatus
Lots of mitochondria

14
Q

Hepatocytes can divide and replicate so the liver can regenerate even if how much is lost?

A

65%

15
Q

What are surrounded by hepatocytes?

A

The sinusoids

16
Q

What are sinusoids?

A

Spaces where blood from hepatic artery and hepatic portal vein mix

17
Q

The mixing of blood in the sinusoids can do what?

A

Increase the oxygen content of the blood supplying hepatocytes with enough oxygen for their needs

18
Q

Sinusoids contain kuppfer cells what do they act as and how?

A

Macrophages

Ingesting foreign particles and helping protect against disease

19
Q

What are the canaliculi?

A

Spaces where hepatocytes secrete bile from breakdown of blood

20
Q

From the canaliculi bile drains into where?

A

Bile ductules which then take it to the gall bladder

21
Q

(Carbohydrate metabolism) hepatocytes are involved in homeostatic control of what?

A

Glucose levels

22
Q

(Carbohydrate metabolism) 1. Carbohydrates are broken down to what and where?

A

Glucose

In the small intestine

23
Q

(Carbohydrate metabolism) 2. What happens to the glucose in the small intestine?

A

Absorbed in to the bloodstream

24
Q

(Carbohydrate metabolism) 3. The glucose in the bloodstream is transported where?

A

To the liver

25
Q

(Carbohydrate metabolism) 4. The liver does what to the glucose?

A

Removes excess and stores it as glycogen

26
Q

(Carbohydrate metabolism) 5. What happens to glycogen between meals?

A

It is broken down between meals as a source of energy

27
Q

(Carbohydrate metabolism) 6. The glycogen is converted to what and released where when blood sugar levels fall?

A

Glucose

Released into bloodstream

28
Q

(Carbohydrate metabolism) 6. Which hormone causes glycogen to be converted to glucose?

A

Glucagon

29
Q

(Deamination) hepatocytes carry out transamination, what is this?

A

Conversion of one amino acid to another

30
Q

(Deamination) why is transamination important?

A

The diet doesn’t always have the correct balance of amino acids

31
Q

(Deamination) deamination involves the removal of what?

A

An amine group from an amino acid

32
Q

(Deamination) deamination is important as the body cannot do what?

A

Store proteins and amino acids they would be wasted and excreted if it weren’t for hepatocytes

33
Q

(Deamination) the amine group is removed and converted to what?

A

Ammonia

34
Q

(Deamination) the ammonia is then converted to what? In which cycle?

A

Urea

The ornithine cycle

35
Q

(Deamination) which is more toxic ammonia or urea?

A

Ammonia

Urea is toxic in high concentrations

36
Q

(Deamination) what happens to the remainder of the amino acid during deamination?

A

Used in cell respiration or converted into lipids

37
Q

In the ornithine cycle ammonia is converted to less toxic urea in a series of what?

A

Enzyme controlled reactions

38
Q

Look over diagram of ornithine cycle

A

Look over diagram of ornithine cycle

39
Q

(Detoxification)Why are levels of toxins in the body always increasing?

A

Metabolic processes producing potentially toxic substances

Choice - alcohol and drug consumption

40
Q

(Detoxification) where in the body are a lot of toxic substances detoxified and made harmless?

A

The liver

41
Q

(Detoxification) what is one example of detoxification?

A

Breakdown of hydrogen peroxide

42
Q

(Detoxification) in breakdown of hydrogen peroxide, what do hepatocytes contain?

A

Catalase

43
Q

(Detoxification) in breakdown of hydrogen peroxide what does catalase do?

A

Breaks down hydrogen peroxide into oxygen and water

44
Q

(Detoxification) what is another example of detoxification?

A

Break down of ethanol toxic drug in alcohol

45
Q

(Detoxification) in ethanol breakdown, what enzyme is found in hepatocytes?

A

Alcohol dehydrogenase

46
Q

(Detoxification) what does alcohol dehydrogenase do?

A

Breaks down ethanol to ethanal

47
Q

(Detoxification) in ethanol breakdown, ethanal is converted to what? And where is this used?

A

Ethanoate

Used to build up fatty acids or used in respiration

48
Q

alcohol produces a toxic enzyme called what?

A

acetaldehyde

49
Q

acetaldehyde can damage the liver, what is its effects?

A

permanent scarring
reduced ability for liver to regenerate
irreversible
decreases life expectancy

50
Q

cirrhosis of the liver is a disease when normal liver tissue is replaced by what?

A

fibrous scar tissue

51
Q

what is the most common cause of cirrhosis?

A

excessive alcohol consumption

52
Q

what are the 3 stages of alcoholic liver disease?

A
  1. alcoholic fatty liver disease
  2. alcoholic hepatitis
  3. liver cirrhosis
53
Q

in alcoholic fatty liver disease what happens to the nuclei of hepatocytes and the liver?

A

displaced by fat filled vesicles

liver gets larger

54
Q

in alcoholic hepatitis the patient has fatty liver, damaged hepatocytes - what else happens?

A

narrowing of the sinusoids and hepatic veins

55
Q

in alcoholic cirrhosis liver tissue is irreversibly damages what happens to hepatocytes? and in turn the liver?

A

many die and are replaced with fibrous tissue
they cant divide and regenerate
liver shrinks
cant deal with toxins as effectively