Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

PHYL2065 > Metabolism > Flashcards

Metabolism Flashcards

1
Q

What is glucose?

A
  • stored as glycogen
  • can be converted to amino acids or fat
  • oxidised for energy, principle fuel in short term
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are fatty acids?

A
  • stored as fat = triaclglycerides (TGs)
  • TGs are glycerol + fatty acids
  • FAs can be oxidised, high energy yield, important in starvation
  • cannot be converted to glucose or amino acids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are amino acids?

A
  • stored as protein polymers of AAs
  • not a primary energy source except starvation
  • excess amino acids are: converted to glucose, converted to fat or some oxidised
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Define metabolism

A

The sum of all reaction in the body; metabolism = catabolic + anabolic reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Define catabolic reactions

A

The breakdown of large macro molecules, such as carbohydrates, lipids and proteins from ingested food or storage molecule into smaller parts, yields energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define anabolic reactions

A
  • synthesis of large molecules from smaller constituent parts, requires energy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

List the anabolic and catabolic reactions of carbohydrates, lipids and proteins

A

Carbohydrates:
glucose -> glycogen (anabolic) glycogen -> glucose (catabolic)
Lipids:
fatty acids -> triacylglycerides (anabolic) triacylglycarides -> fatty acids (catabolic)
Proteins:
amino acids -> proteins (anabolic) proteins -> amino acids (catabolic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the function of the liver in digestion?

A
  • intestinal blood supply flows directly to the liver, so ‘first pass’ metabolism occurs in the liver
  • linked closely to the pancreatic blood supply, so hormones insulin/glucagon exert their effects at the liver first
  • liver stores glucose as glycogen (glycogenesis) which it can breakdown when required (glycogenolysis) and release to the body - muscles are the main store + utilisation of glycogen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What other substances can the liver synthesise?

A
  • can synthesise ketones, from fatty acids and amino acids (ketogenesis), as an alternative energy source when carbohydrates are sparse (synthesis of ‘new glucose - gluconeogenesis)
  • can also synthesise lipids (TGs) from glucose and amino-acids (lipogenesis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is fat/adipose tissue?

A
  • major site (normally) of lipids (TGs) storage and release
  • releases glycerol backbone and FAs during starvation
  • glycerol backbone + fatty acids = new glucose
  • glycerol is used to make new glucose by liver
  • FAs are an alternative energy source to glucose
  • not all fats are the same
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Discuss metabolism and the brain

A
  • the brain has a very high metabolic rate and high blood supply
  • depends mainly on glucose
  • blood glucose levels are under strict control by insulin/glucagon
  • if levels fall between severely low (2 mmol/L) results in impaired brain function, coma and death
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the key tissues in metabolism?

A

liver - produces glucose and stores glycogen
brain - obligate glucose user
muscle - stores glycogen
white adipose tissue - stores fat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the key hormones responsible for promoting storage?

A
  • insulin (promotes anabolic reactions; formation of storage molecules)
  • GH (protein)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the key hormones responsible for promoting mobilisation?

A
  • glucagon
  • catecholamines (adrenaline and noradrenaline) and cortisol - both involved in sympathetic response to starvation
  • GH (fats, CHOs) - (roids) growth hormone: protein anabolic, fat catabolic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What type of hormone is insulin?

A

An anabolic hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What type of hormone is glucagon?

A

A catabolic hormone

17
Q

What are some WHO criteria for metabolic syndrome?

A
  • impaired glucose regulation/insulin resistance
  • abdominal/central obesity
  • hypertriglycemia
  • low levels of HDL cholesterol
  • raised blood pressure
  • microalbuminuria
18
Q

Discuss fat accumulation

A
  • adipose tissue is a highly active metabolic and endocrine organ
  • adipocytes are the primary cell type of adipose tissue
  • adipose is the primary site of storage for excess energy
  • adipocytes synthesise a number of biologically active compounds that regulate metabolic homeostasis
19
Q

Why is a pro-inflammatory profile dangerous?

A
  • the distance between cells and their blood supply needs to be short to allow diffusion
  • if this distance is greater, and too great, it can cause hypoxia and necrosis
20
Q

What is insulin insensitivity/resistance?

A
  • insulin signalling regulates glucose, lipid and fat metabolism
  • insulin receptors are expressed on the cells of the Skm, liver and adipose tissues
  • insulin insensitivity is defined where insulin levels are normal or elevated, but target cells become less sensitive to insulin
  • consequences: hyperglycaemia and compensatory hyperinsulinemia
21
Q

What is diabetes mellitus, and some symptoms?

A
  • disease of impaired carbohydrate, fat and protein metabolism
  • characterised by hyperglycaemia
  • more frequent urination (polyuria)
  • increased thirst (polydipsia)
  • increased appetite (polyphagia)
22
Q

What are some features of type 1 DM?

- insulin secretion, age of onset, speed of onset, defect, treatment and management

A
  • no insulin secretion
  • early age of onset
  • rapid onset
  • destruction of beta cells (produce insulin; anabolic, increases storage of glucose, fatty acids and amino acids)
  • treated with insulin, exercise, diet
23
Q

What are some features of type II DM?

- insulin secretion, age of onset, speed of onset, defect, treatment and management

A
  • normal or increased insulin secretion
  • late-adult/obesity
  • slow onset
  • insulin resistance
  • weight reduction, diet, exercise, drug
24
Q

What are the purposes of metabolic pathways?

A
  • extraction of energy
  • storage of fuels
  • synthesis of important building blocks
  • elimination of waste materials
25
Q

What is ATP, and what does it supply energy for?

A

ATP is temporary energy storage molecules in all cells
Energy for:
- synthesis, to make macromolecules
- transport (pumps) often against concentration gradient
- muscle contractions and cell motility

26
Q

List some important metabolic reactions for humans

A
  • glycolysis
  • citric acid cycle
  • oxidative phosphorylation
  • urea cycle
  • fatty acid beta cell oxidation
  • gluconeogenesis
27
Q

What are the major lipid pathways?

A
  • lipolysis: hydrolysis of mainly TGs produce glycerol and FAs
  • beta-oxidation: conversion of FAs into acetyl choline acid
  • lipogenesis: cholesterol and other lipids synthesis
  • ketogenesis: formation of ketone bodies

PHYL2065 (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions