Lecture 7: Respiration Flashcards

1
Q

What are the major fuel types?

A

Carbohydrates:
broken down to simple sugars

Proteins:
broken down to amino acids

Fats:
broken down to simple fats

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

Are all cellular processes spontanous?

A

No. Many cellular processes require energy.
For example, cilia beating

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

What is cellular energy?

A

ATP
Adenosine tri-phosphate

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

What does the ATP cycle describe?

A

The transfer of energy between complex and simple molecules in the body, with ATP as the mediator.

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

What is the simplest chemical equation of respiration?

A

C₆H₁₂O₆ + 6 O₂ –> 6 CO₂ + 6 H₂O + Energy

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

What are the steps of the conversion of glucose to ATP?

A
  1. Glycolysis
  2. Pyruvate oxidation (Link Step)
  3. Citric Acid Cycle (KERBS Cycle)
  4. Oxidative Phosphorylation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Where does Glycolysis occur?

A

Occurs in cytosol (Outside the mitochondria)

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

What functions require Oxygen?

A

Glycolysis - Oxygen Not Required
Pyruvate Oxidation - Oxygen Required
Citric Acid Cycle - Oxygen Required
Oxidative Phosphorylation - Oxygen Required

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

What is the Net Chemical result of Glycolysis?

A

Glucose –> 2 Pyruvate (Pyruvic Acid) + 2 H₂0
4 ATP Produced – 2 ATP used –> 2 ATP Net
2 NAD⁺ + 4 e⁻ + 4 H⁺ –> 2 NADH + 2 H⁺

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

How many carbons does Glucose have?

A

6 Carbon-base

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

How many carbons does Pyruvate (Pyruvic Acid) have?

A

3 Carbon-base

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

What are the phases of Glycolysis?

A

Energy Investment Phase
Energy Payoff Phase

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

What is the chemical equation of the Energy Investment Phase of Glycolysis?

A

2 ATP –> 2 ADP + 2 P

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

What is the chemical equation of the Energy Payoff Phase of Glycolysis?

A

4 ADP + 2 P –> 4 ATP
2 NAD⁺ + 4 e⁻ + 4 H⁺ –> 2 NADH + 2 H⁺

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

What is the chemical equation for Glucose in Glycolysis?

A

Glucose –> 2 Pyruvate (Pyruvic Acid) + 2 H₂0

C₆H₁₂O₆ –> C₃H₄O₃ + 2 H₂0

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

What does Pyruvate Oxidation (Link Step) do?

A

This step links glycolysis to the citric acid cycle

Turns the Pyruvate (3C) into Acetyl CoA (2C)

Acetyl CoA can enter the citric acid cycle, Pyruvate cannot

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

Where does Pyruvate Oxidation (Link Step) happen?

A

Occurs in the mitochondrial matrix

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

What are the products of the Pyruvate Oxidation (Link Step)?

A

No ATP,
1 NADH per pyruvate (or 2 per glucose) plus 1 CO₂

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Where does the Citric Acid Cycle occur?

A

In the Mitochondria Matrix

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

What are the products of the Citric Acid Cycle?

A

Results in:
2 ATP
6 NADH
2 FADH₂
4 CO₂
(per glucose molecule)

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

Does the Citric Acid Cycle require Oxygen?

A

Requires oxygen – it is an aerobic process

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

What are NADH and FADH₂?

A

FADH₂ and NADH are electron donors in the electron transport chain

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

What level of extraction is there after the Citric Acid Cycle?

A

The citric acid cycle completes the extraction of energy from glucose

No more carbon bonds to be broken

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What makes up Oxidative Phosphorylation?

A

Electron Transport Chain + Chemiosmosis

25
What types of reactions are...? 1. Glycolysis 2. Citric Acid Cycle (KERBS Cycle)
Substrate phosphorylation (Direct Transfer): ATP generated by direct transfer (from a substrate) of a phosphate group to ADP Glycolysis and Citric acid cycle make ATP via substrate phosphorylation
26
What is the definition of Oxidative Phosphorylation?
Oxidative phosphorylation (Free Phosphates): ATP is generated from the oxidation of NADH and FADH₂ and the subsequent transfer of electrons and pumping of protons Bulk of ATP production happens here
27
What does Cyanide do?
Cyanide blocks passage of electrons to O₂ at complex 4. Resulting in the death of the cell.
28
Where does the Election Transport Chain occur?
Occurs at proteins at the inner membrane
29
Does the Electron Transport Chain require Oxygen?
Requires Oxygen – Aerobic process Oxygen “pulls” the electrons down the chain, and is then the final electron acceptor where it is reduced to water 2 H⁺ + ½ O2 --> H₂O)
30
What are used in the Electron Transport Chain?
NADH and FADH₂ from Glycolysis and the Citric acid cycle are used here
31
What are the helper proteins for the Electron Transport Chain?
Q and Cyt c are helper proteins.
32
What are the Protein Complexes involved in the Electron Transport Chain?
Requires Complex 1, 2 (peripheral), 3, 4 All are hydrogen pumps
33
What Protein Complexes accept which electron donors?
NADH --> Complex 1 + NAD⁺ FADH₂ --> Complex 2 + FAD
34
What is the function of Chemiosmosis?
(Waterfall) High concentration of Hydrogens drive down through ATP Synthase, tumbling through to create ATP from ADP + P The rotation of the ATP synthase turbine enables the phosphorylation of ADP to generate ATP
35
How much ATP does Chemiosmosis produce?
26 ~ 28 ATP per glucose!
36
What is the 'gate-keeper' for Glycolysis?
Phosphofructokinase It catalyzes step 3 – where glycolysis becomes irreversible
37
What is the 'gate-keeper' of Glycolysis inhibited by?
inhibited by citrate and ATP ie. products of cellular respiration
38
What is the 'gate-keeper' of Glycolysis stimulated by?
stimulated by AMP AMP accumulates when ATP is being used rapidly
39
What is the definition of Homeostasis?
The maintenance of relatively constant conditions within physiologically tolerable limits
40
What is Insulin produced by?
Produced by beta cells of Islets of Langerhans in pancreas
41
What is the function of Insulin?
Promote glucose uptake into cells (for ATP production or storage in liver)
42
What is Glucagon produced by?
Produced by alpha cells of Islets of Langerhans in pancreas
43
What is the function of Glucagon?
Stimulates the breakdown of glycogen (Cross-linked glucose in liver/skeletal muscle) to increase blood sugar levels
44
What happens if you lose the function of insulin?
* No glucose in cells * No ATP from glucose * No glycogen stored for harder times
45
What is Diabetes Mellitus?
The ability to produce or respond to the hormone insulin is impaired results in abnormal metabolism of carbohydrates and elevated levels of glucose in the blood
46
What is Type 1 or insulin-dependent diabetes?
Body does not produce insulin, as beta cells of pancreas are destroyed, often this is autoimmune, or genetic or through environmental factors Affects 5 – 10 % of diabetics, and onset usually occurs in children or adolescents. Requires insulin replacement
47
What is Type 2 or non-insulin-dependent diabetes?
Body produces insulin, but receptors are non functional (insulin resistance) Most (>90%) diabetics are Type II, usually adults over the age of 40 Can be linked to other pathologies and obesity
47
What are the steps of Diabetes mellitus as caused by a lack of functional insulin?
As a result, levels of glucose in the blood build up, well beyond normal homeostatic limits. Increased blood glucose alters the volume and osmolarity of blood, with subsequent pathological consequences.
48
What are the symptoms of Diabetes mellitus as caused by a lack of functional insulin?
Significantly increased hunger Significant weight loss
49
What is the mmol/L levels for fasting?
≥7mmol/L
50
What is it called when Homeostasis is disturbed by increasing glucose levels?
Hyperglycemia
51
What is it called when Homeostasis is disturbed by decreasing glucose levels?
Hypoglycemia
52
What is the receptor for decreasing glucose levels?
Alpha Cells in Pancreatic Islets --> Secrete glucagon
52
What are the effectors for decreasing glucose levels?
Liver, Skeletal Muscle, Adipose Tissue
53
What is it called when Homeostasis is disturbed by increasing glucose levels?
Hyperglycemia
54
What is the receptor for increasing glucose levels?
Beta Cells in Pancreatic Islets --> Secrete Insulin
55
What are the effectors for increasing glucose levels?
All body cells
56
What do the effectors for increasing glucose levels respond with?
Increased rate of glucose transport into target cells Increased rate of glucose use and ATP generation Increased conversion of glucose to glycogen Increased amino acid absorption and protein synthesis Increased triglyceride (fat) synthesis in adipose tissue
57
What do the effectors for decreasing glucose levels respond with?
Increased breakdown of glycogen to glucose (in liver, skeletal muscle) Increased breakdown of fat to fatty acids (in adipose tissue) Increased synthesis and release of glycose (in liver)