B2 2019 Flashcards
3.3 Explain why the lids were kept on the petri dishes
To prevent evaporation
Alters concentration of IAA solution
3.4 Describe and explain the results how the results might have differed if lengths of root had been used
IAA stimulates cell elongation
Increase in IAA concentration the higher the mean
IAA inhibits cell elongation in roots
5.1 Describe the role of glucagon in gluconeogenesis
Attaches to receptors on target cells and stimulates enzymes
Glycerol -> Glucose
5.3 Explain how increasing a cells sensitivity to insulin will lower the blood glucose concentration
Insulin binds to receptors
Simulates uptake of glucose by channel proteins
Activates enzymes which convert glucose to glycogen
5.4 Explain how inhibiting adehylate cyclase may help to lower the blood glucose concentration
Less ATP converted to cAMP
Less kinase is activated
Less glycogenolysis
7.3 Explain why the student marked the origin using a pencil rather than ink
Ink and pigments would mix
7.4 Describe the method the student used to separate the pigments after the solution of pigments had been applied to the origin
Level of solvent below origin
Remove before reaches top
8.1 What is DNA probe
Single strand of DNA
Bases complementary
8.3 The DNA on the nylon membrane is treated to form single strands
DNA probe binds
9.2 Suggest and explain how digesting insects helps the sundew to grow in soil with very low concentrations of some nutrients
Digestion of proteins
Provides amino acids
10.2 Sometimes Guillain Barre syndrome causes hear rate irregularities. Suggest and explain why
Less being sent to the medulla oblongata by the SAN along sympathetic pathway
From Medulla to SAN
10.3 The first successful drug trail to reduce concentrations of Huntington in the brain used single stranded DNA, Suggest and explain how this drug could cause a reduction in the concentration of protein huntington
DNA is complementary to mRNA
Binds to mRNA
Prevents translation
