What is cellular respiration?
A series of enzyme‑controlled metabolic pathways that release energy from glucose.
What are the three stages of aerobic respiration?
Glycolysis, the citric acid cycle, and the electron transport chain.
Where does glycolysis occur?
In the cytoplasm.
What is glycolysis?
The breakdown of glucose into pyruvate in the cytoplasm.
What happens in the energy investment stage of glycolysis?
ATP is required to phosphorylate glucose and intermediates.
What happens in the energy pay‑off stage of glycolysis?
More ATP is generated than was used, giving a net gain of ATP.
What is the net gain of ATP from glycolysis?
2 ATP.
Which enzymes remove hydrogen ions and electrons during glycolysis?
Dehydrogenase enzymes.
What molecule accepts hydrogen ions and electrons during glycolysis?
NAD, forming NADH.
Where does NADH from glycolysis go
To the electron transport chain.
What happens to pyruvate in aerobic conditions?
It is broken down to an acetyl group.
What happens during the breakdown of pyruvate?
Carbon dioxide is released and hydrogen ions and electrons are passed to NAD to form NADH.
What carries the acetyl group to the citric acid cycle?
Coenzyme A.
What is formed when an acetyl group joins coenzyme A?
Acetyl coenzyme A (acetyl CoA)
Where does the citric acid cycle occur?
In the matrix of the mitochondria.
What does the acetyl group combine with to begin the citric acid cycle?
Oxaloacetate.
What is the first product of the citric acid cycle?
Citrate.
What happens to citrate during the citric acid cycle?
It is gradually converted back into oxaloacetate.
What is released during the citric acid cycle?
Carbon dioxide.
What is generated during the citric acid cycle?
ATP and NADH.
Which enzymes remove hydrogen ions and electrons during the cycle?
Dehydrogenase enzymes.
Where does NADH from the citric acid cycle go?
To the electron transport chain.
Where is the electron transport chain located?
On the inner mitochondrial membrane.
What is the electron transport chain made of?
Carrier proteins attached to the inner mitochondrial membrane.
-
Unit 1-Division And Differentiation In Human Cells26
-
Unit 1-Structure And Replication Of DNA33
-
Unit 1-Gene Expression30
-
Unit 1-Mutations30
-
Unit 1-Human Genomics10
-
Unit 1-Metabolic Pathways30
-
Unit 1-Cellular Respiration34
-
Unit 1-Energy Systems In Muscle Cells24
-
Unit 2-Gamete Production And Fertilisation32
-
Unit 2-Hormonal Control of Reproduction23
-
Unit 2-The Biology Of Controlling Fertility24
-
Unit 2-Antenatal And Postnatal Screening62
-
Unit 2-The Structure And Function of Arteries, Capillaries And Veins31
-
Unit 2-The Structure And Function Of The Heart58
-
Unit 2-Pathology Of Cardiovascular Disease (CVD)38
-
Unit 2-Blood Glucose Levels And Obesity35
-
Unit 3-Divisions Of The Nervous System And Neural Pathways31
-
Unit 3-The Cerebral Cortex7
-
Unit 3-Memory25
-
Unit 3-The Cells Of The Nervous System And Neurotransmitters At Synapses31
-
Unit 3-Non-Specific Body Defences27
-
Unit 3-Specific Cellular Defences Against Pathogens34
-
Unit 3-Immunisation16
-
Unit 3-Clinical Trials Of Vaccines And Drugs11
