Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Metabolism - Alex's Cards (ESA2) > Session 1 Lecture Notes > Flashcards

Session 1 Lecture Notes Flashcards

1
Q

What do catabolic processes do?

A

Break down molecules to release energy in the form of reducing power
Energy from catabolic processes drives anabolic processes

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

What do anabolic processes do?

A

Use energy and raw materials to make larger molecules for growth and maintenance

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

What is biosynthetic work?

A

Synthesis of cellular components

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

What percentage of the brains’ energy is used for transport work and give an example

A

50%

NA, K ATPase

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

What form of energy is used in our bodies to drive every biological reaction?

A

Chemical bond energy

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

What are the 3 components of ATP?

A

Adenine ring
Ribose sugar
3 phosphate groups (alpha beta and gamma)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Where is the energy source obtained from in ATP?

A

In the last phosphodiester bond - the energy is released when the bond is broken

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

Using oxidation give three examples of where energy can be obtained?

A

Carbohydrates
Lipids
Protein - in times of need
Alcohol - but dangerous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the official unit of food energy?

A

Kilojoules (kJ)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What does calorie actually refer to? How many calories in a kilojoule?

A

Calorie (kcal) = kilocalorie
So 1 calorie is actually 1000 calories
1 calorie = 4.2 kilojoules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is fibre necessary for?

A

Maintaining normal GI function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the formula for carbohydrate?

What does carbohydrate contain?

A

(CH20)n
Aldehyde or keto groups
Multiple OH groups

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

What is a monosaccharide?

A

A single sugar unit e.g. glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How many carbons do the following monosaccharides contain?
Triose sugar
Pentose sugar
Hexose sugar

What is glucose classified as?

A

Triose = 3 carbons
Pentose = 5 carbons
Hexose = 6 carbons
Glucose contains 6 carbons so is a hexose sugar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are disaccharides?

A

2 simple sugar units linked together (2 monosaccharides)

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

What are oligosaccharides?

A

3-12 simple sugar units linked together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are polysaccharides? Give 3 examples

A

More than 10 simple sugar units linked together - up to thousands
e.g. cellulose, starch and glycogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What 2 sugars make up the disaccharide sucrose (table sugar)?
What 2 sugars make up the disaccharide lactose (milk sugar)?

A 
Sucrose = glucose-fructose
Lactose = galactose-glucose
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is fructose and what form of sugar is it?

A

Fruit sugar

Monosaccharide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Maltose is a disaccharide. What sugars compose it?

A

Glucose-glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What does digestion break protein down into?

A

Amino acids which enter the bloodstream

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are essential amino acids and how many are there?

A

They are AAs that we cannot synthesise (can only be obtained from our diet)
9 out of 20 AAs in our body are essential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Try and name as many of the essential AAs as you can

Clue = If learned this huge list may prove truly valuable

A 
Isoleucine
Lysine
Threonine
Histidine
Leucine
Methionine
Phenylalanine
Tryptophan
Valine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What does conditionally essential mean when referring to AAs?

A

They are essential at periods of rapid growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What 3 AAs may pregnant women and children also require?
Arginine Tyrosine Cysteine As they cannot be synthesised at the required rate
26
Give an example of a high quality and low quality source of protein. Why are they classified in this way?
High = animal origin Low = plant origin High contain all essential AAs Low are deficient in one or more essential AAs
27
What are triacylglycerols?
3 fatty acids esterified to one glycerol (compose lipids)
28
What are the fat soluble vitamins?
A D E and K
29
Give 2 examples of essential fatty acids
Linoleic | Linolenic
30
What are the 3 major electrolytes?
Sodium Potassium Chloride
31
What is the routine maintenance (IV fluids) for 1) the key electrolytes 2) water
1) 1 mmol per kg per day (of each = sodium, potassium and chloride) 2) 30ml per kg per day
32
What causes the disease pellegra?
Deficiency in niacin vitamin
33
Deficiencies in which 2 vitamins can cause anaemia?
B12 | Folate
34
Why can't humans break down the polysaccharide cellulose? (a polymer of glucose)
Because humans don't have the enzymes needed to break down the beta-1,4 links in cellulose
35
What is the RNI and what is it used for?
Reference Nutrient Intake | Used for proteins, vitamins and minerals
36
What is EAR and what is it used for?
Estimated Average Requirement Used for energy Is the approximate value that the mean person requires (50% will require more)
37
What is LRNI?
Lower reference nutrient intake Intakes below this are insufficient for most people It is the what the average person at 2.5% on graph requires
38
What is RNI?
Reference nutrient intake | It is what the average person at 97.5% on the graph requires
39
How is daily energy expenditure calculated? | 3 measurements
1) BMR - basal metabolic rate 2) DIT - diet induced thermogenesis (energy to process food) 3) PAL - physical activity levels
40
How is BMI calculated?
Body Mass Index BMI = weight (kg) / height2 (m2)
41
What is the normal fasting plasma concentration for glucose?
3.3-6.0 mmol/L
42
What is the enzyme in saliva and what does it do?
Amylase | Breaks down starch and glycogen into dextrins
43
What is broken down in the small intestine and what are the enzymes involved?
Amylase is secreted through ducts in the pancreas into the duodenum which breaks down monosaccharides (breaks down the alpha-1,4 bonds) The cells attached to the villi of epithelium secrete disaccharidases which break down glucose lactose and maltase
44
What causes a lactose intolerance?
Lack of enzyme lactase so the lactose is not broken down properly
45
Explain the following: 1) Primary lactose deficiency 2) Secondary lactose deficiency 3) Congenital lactose deficiency
1) an absence of lactase persistence allele (can't break down lactose) 2) caused by injury to small intestine 3) extremely rare - autosomal recessive defect in lactase gene means baby cannot digest breast milk
46
Active transport is used in small intestines to move monosaccharides into bloodstream across 2 sides of the epithelium lumen. What are these sides and what are the transporters?
1) Apical side (facing lumen of small intestines) = the SGLT1 transporter is used (sodium dependent glucose transporter 1) where co transport of 2 sodium ions with 1 glucose 2) Basolateral side = the GLUT2 transporter used to move into blood supply (uniport)
47
How is glucose taken up in the cells from the blood?
Via facilitated diffusion (GLUT1-5 transporters)
48
Where are GLUT2 tranporters primarily found?
In the kidney, liver, pancreatic beta cells and small intestine
49
Where are GLUT4 transporters primarily found?
In adipose tissue, skeletal muscle and insulin regulated
50
Give 4 examples of cells for which glucose is an absolute requirement (only source of energy)
1) Erythrocytes 2) Neutrophils 3) Innermost cells of kidney medulla 4) Lens of the eye
51
What is glycolysis?
Oxidation of glucose (monosaccharide) to 2 pyruvate molecules
52
What is the net gain of ATP in glycolysis?
2 First reaction in glucose catabolism uses 2 ATP molecules 2nd reaction creates 4 ATP molecules
53
How many units of NADH are produced during glycolysis?
2 NADH molecules per 1 molecule of glucose
54
What are the 3 key enzymes in glycolysis and what intermediaries do they convert?
1. Hexokinase (glucokinase in liver) Converts glucose into Glucose-6-phosphate 2. Phosphofructokinase-1 Concerts Fructose-6-phosphate into Fructose 1,6-bis-phosphate 3. Pyruvate kinase Coverts Phosphoenolpyruvate into Pyruvate
55
What does phosphorylation of glucose to glucose-6-phosphate do?
Makes glucose negatively charged | Prevents glucose moving back across cell down concentration gradient
56
What does having a large negative delta G mean?
That the reaction is irreversible
57
What enzyme is the key regulator of glycolysis?
Phosphofructokinase
58
In which 2 ways is phosphofructokinase regulated?
1. Allosteric regulation (High ATP = inhibits PFK activity, high AMP = stimulates PFK activity) 2. Hormonal regulation (Large intake of nutrients = stimulation of activity of PFK by insulin, and inhibited by glucagon)
59
Explain how levels of NADH and NAD+ are metabolically regulates
High levels of NADH or low levels of NAD+ = high energy signals Cause inhibition of glycolysis
60
How is the enzyme pyruvate kinase regulated?
Activity of enzyme increases when there is a high insulin:glucagon ratio e.g. high levels of insulin and low levels of glucagon
61
Where is glucagon produced and what does it do?
It is a hormone produced by alpha cells of the pancreas | It raises the levels of glucose in the bloodstream (causes liver to convert stores glycogen into glucose)
62
Where is insulin produced and what does it do?
It is a hormone produced by beta cells of the pancreatic islets of langerhans Promotes the absorption of glucose and anabolism (converting glucose into glycogen stores)
63
NAD+ is needed in glycolysis as it converts to NADH. NAD+ can be regenerated from 2 routes what are they?
Regenerated from NADH | Regenerated by lactate dehydrogenase (LDH)
64
What does lactate dehydrogenase convert?
NADH + H+ + pyruvate --> NAD+ + lactate
65
What is the process called when pyruvate is converted back to glucose and where does this take place?
Glucogenesis | In the liver and kidney
66
What is lactic acidosis and what does it cause?
It is a plasma lactate level of over 5mM (above the renal threshold level = kidneys can no longer excrete it) It lowers the blood pH
67
Deficiency in which 3 enzymes can cause galactosaemia?
1. Glactokinase 2. Uridyl tranferase 3. UDP-galactose epimerase
68
What are the 2 main enzymes involved in metabolising fructose?
Fructokinase | Aldolase
69
What is essential fructosuria?
Missing enzyme fructokinase | Leads to fructose in urine but no clinical signs
70
What is fructose intolerance?
Missing enzyme aldolase | Fructose-1 phosphate accumulates in the liver and can lead to liver damage
71
What enzyme is the start of the pentose phosphate pathway and what does it convert?
Glucose 6 phosphate dehydrogenase enzyme | Converts glucose 6 phosphate to 6-phosphogluconolactone
72
What is the end product of the pentose phosphate pathway and what does it produce along the way?
Along the way NADPH is produced (needed for fatty acid and steroid biosynthesis) Pentose phosphate pathway produces ribose 5 phosphate (needed for DNA and RNA synthesis)

Metabolism - Alex's Cards (ESA2) (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions