The importance of proteins in the control of processes and responses in organisms

Question 1

A01 - Proteins and Enzymes

Answer 1

• structure of proteins: amino acids, peptide bonds, level of structure
• enzymes: tertiary structure determines active site shape (induced fit model) enzyme substrate complex

Question 2

A02 - Proteins and Enzymes

Answer 2

• Control of reactions - enzymes lower activation energy to allow metabolic pathway to occur at body temperature
• Example: ATP synthase in respiration

Question 3

A01 - Mitosis and Spindle Fibres

Answer 3

• Spindle fibres attach to centromeres and talk through all of the stages of mitosis, but focus on when spindle fibers are forming, what they are attaching to, what they’re splitting and moving apart
• Separate chromatids during mitosis

Question 4

A02 - Mitosis and Spindle Fibres

Answer 4

• Protein control here is vital for genetic stability - errors lead to cancer or genetic disorders (eg Down’s syndrome from non-disjunction)

Question 5

A01 - Transcription Factors and Gene Expression

Answer 5

• Proteins in controlling transcription. Transcription factors bind to DNA to regulate gene expression
• How transcriptional factors control whether transcription occurs or not

Question 6

A02 - Transcription Factors and Gene Expression

Answer 6

• Cell differentiation: Making specialized cells is possible because of transcriptional factors
• Or in development and disease - e.g. tumor suppressor gene (cancer)

Question 7

A01 - Control of Blood Glucose

Answer 7

• Insulin and glucagon are 2 hormone which are both proteins and they are controlling the process of blood glucose control

Question 8

A02 - Control of Blood Glucose

Answer 8

• This is important because its maintaining blood glucose control
• Insulin - The importance is that it lowers it so that you dont have too negative of water potential, which would cause water to leave the cells, moving to the blood by osmosis and would increase blood pressure and also they wouldn’t be able to create glycogen stores without insulin (you could link it to diabetes)

Question 9

A01 - The water potential of the blood

Answer 9

• ADH is a protein hormone that binds to receptiors on the cell surface membrane of the collecting duct and the distal convoluted tubule
• Production in the hypothalamus and the release for the posterior pituitary gland into the blood
• Triggers insertion of aquaporins via a second messenger model

Question 10

A02 - The water potential of the blood

Answer 10

• Controlling water reabsorption to maintain that constant level or water potential of the blood because if it was too negative you are going to be dehydrated
• To much water in the blood - water moves into cells by osmosis causing them to burst