Essays

Question 1

ATP

Answer 1

-General outline of ATP. Why ATP is good energy store. Used in: metabolic processes, movement, active transport, secretion and activation of molecules(phosphorylation).
Photosynthesis/respiration
Active transport
Muscle contraction
Homeostasis
Sodium potassium pump in co transport of glucose/amino acids and also resting membrane potential.

Question 2

Complementary shapes

Answer 2

Digestion
Mutations
Immunity, antibodies
Photosynthesis
Enzymes and proteins, protein synthesis
DNA, DNA rep.
Haemoglobin
Any process with enzymes.
Synaptic transmission?
CSM structure
Transcriptional factors, siRNA, oestrogen
Control of mammalian oestogen cycle

Question 3

Ions

Answer 3

Resp,PS
Eutrophication
Transport in plants
Osmosis
Nitrogen and phosphorus cycle
Glucose co transport
Action potentials.

Question 4

Cycles

Answer 4

Krebs
Calvin
Nitrogen
Cardiac
phosphorus
Breathing?
Cell

Question 5

Membranes

Answer 5

HIV rep
Osmosis
Co transport
Diffusion
Active transport
Action potentials and synaptic transmission
PS/resp
CSM structure

Question 6

Enzymes

Answer 6

PS, resp
Protein synthesis
Digestion
DNA rep
ATP
Lock and key, induced fit, competitive/ non competitive inhibitors.
Nitrogen cycle
Digestion

Question 7

Bonding

Answer 7

Lipids- ester bonds
Nitrogen cycle N triple bond N
Protein synthesis/DNA rep- phosphodiester bonds, H bonds broken
Protein structure then Hb structure determined by amino acids and then same with RBC’s so sickle cell disease.
ATP
Carbs- glycosidic bond
DNA
Mutations

Question 8

Interactions between organisms and cells

Answer 8

Nitrogen cycle and eutrophication
Inter and intraspecific competition
HIV/most of immunity
Tissue fluid
Courtship behaviour
Energy transfers in food chains
Succession

Question 9

Nitrogen

Answer 9

Nitrogen cycle
Fertilisers, eutrophication
Amino acids so protein structure
DNA- nitrogenous bases
Co transport of amino acids
Hb is protein so has N
Protein synthesis
PS/resp
Any enzymes

Question 10

Diffusion

Answer 10

Gas exchange in humans, fish and insects.
Co transport of glucose/amino acids
Resp/PS
Digestion/absorption of lipids
Mass transport of sucrose
Osmosis? (Diffusion of water)

Question 11

Polymers

Answer 11

Digestion
Enzymes
Hb
DNA
Biological molecules, starch, glycogen, cellulose.

Question 12

Link for flashcards to use

Answer 12

https://quizlet.com/gb/300036954/aqa-a-level-biology-25-mark-essays-flash-cards/

Question 13

CO2

Answer 13

Calvin cycle
PS, also limiting factor for PS
Hb- bohr effect
Inhalation/exhalation
Receptors- Bohr effect