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Biology

A Level

What is the Krebs cycle?

Photosynthesis has four stages:

Glycolysis.
The Link Reaction.

3. The Krebs Cycle.

Oxidative Phosphorylation...

Answered by Megan S. • Biology tutor

7823 Views

Name the first stage of respiration. How many net ATP molecules are produced?

Glycolysis - 2 ATPs (net) are produced. 2 are input into the reaction and 4 are produced as a result.

Answered by Lydia W. • Biology tutor

2990 Views

How does the body's response to a second infection by a bacterial pathogen differ from the first? (3 marks)

faster response due to the presence of memory cells

there are many more cells specific for this pathogen therefore clonal selection and expansion of B cells is quicker

BT
Answered by Beth T. • Biology tutor
3031 Views

Explain the role of inorganic ions in the body.

The resting membrane potential of cells is maintained by the actions of Na+ and K+. A resting cell is impermeable to Na+ so the concentration of Na+ is greater outside the cell than in it. However the cel...

Answered by Callum D. • Biology tutor

7733 Views

During succession the species present changes. Explain why.

The pioneer species (or any other species) changes the environment, making it less hostile. Also some species are better competitors and out-compete others.

Answered by Alfie B. • Biology tutor

8930 Views