cell metabolism + use of chem+G1 shit

Question 1

Cell metabolism:

Answer 1

Involves the synthesis and breakdown of macromolecules.

Question 2

Glycolysis:

Answer 2

occurs in many regulated steps. Each step is regulated by an enzyme. Intermediate compounds are created by these enzymes. This converts glucose to pyruvate (x2) which produces 4 ATPs, double the 2 we started with. Fermentation. Occurs in the cytoplasm.

Question 3

Use of chemicals effects

Answer 3

1. Can interfere with metabolic reactions by disabling and denaturing enzymes and other proteins.
2. Can cause cancer through mutagenic chemicals acting as carcinogens
3. Amanitin is a chemical that can stop mRNA synthesis, as mRNA is required for the process of protein synthesis in the ribosomes that means that this chemical thereby prevents the production of essential proteins and enzymes that are essential for important metabolic reactions, thereby inhibiting cellular functions.
4. Actinomycin is a chemical that can stop RNA synthesis, as mRNA is required for the process of protein synthesis in the ribosomes that means that this chemical thereby prevents the production of essential proteins and enzymes that are essential for important metabolic reactions, thereby inhibiting cellular functions.

Benefits
1. Antibiotics can be used to kill bacteria that may cause infection.

Question 4

Controlling cell division through the cell cycle
* G1 Growth phase (interphase):

Answer 4

1. Is metabolically active
2. Organelles and the components of the cytoplasm get duplicated
3. Centrosomes start to get replicated
4. Lasts 8-10 hours
5. End of the cell cycle for non-dividing cells

Question 5

G1 checkpoint or R restriction checkpoint checks for:

Answer 5

1. Growth
2. Nutrients
3. Growth factors
4. DNA damage
5. Last 6-8 hours
   - If these factors are not met then the cell cycle stops and the cell will not reproduce or continue to grow, it will just continue to carry out metabolic processes.

Question 6

Synthesis/S phase:

Answer 6

1. DNA is replicated

Question 7

G2 phase:

Answer 7

1. Cell continues to grow
2. Enzymes and proteins are synthesised
3. Replication of centrosomes is completed
4. 4-6 hours

Question 8

G2 checkpoint checks for:

Answer 8

1. Growth
2. DNA replication
3. The presence of an enzyme called cyclin-dependent kinase along with the increase in presence of Cyclins which is a regulatory protein that activates this enzyme.
4. These combine to form mitosis promoting factor complex (MPF) which is required for prophase and metaphase, therefore these phases require an increase in MPF to stimulate them. As such an increase in cyclin results in an increase of MPF.

Question 9

Carcinogens are any factor that leads to a change in nucleotide sequence

Answer 9

Examples:
-ionizing radiations
-mutagenic chemicals
-viruses