June 2020 2Br

Question 1

How to clone a bull

Answer 1

• nucleus from body cell of a bull
• insert nucleus into a enucleated egg
  -electric shock
• mitosis
• embryo into uterus
• surrogate mother

Question 2

GH increases transcription in cells.
Explain why this affects the growth of rats.

Answer 2

• more mRNA created
• more translation
• more protein
• enzymes

Question 3

Describe the different types of pathogen.
Refer to a disease that each type of pathogen causes in your answer.

Answer 3

Virus = non living organism
eids

Bacteria= prokaryotic
Pneunomia

Fungus= cannot photosynthesis
Athelete’s foot

Protosticst
Malaria

Question 4

How vaccine help a person

Answer 4

• Inactive pathogen in vaccine
• carrying antigens
• lymphocytes produce antibodies
• memory cells is produced
• remains in blood
• faster antibodies produced if happens again

Question 5

Explain how a change in the DNA of a microorganism can reduce its ability to
digest a substance.

Answer 5

• diff sequence of bases in DNA
• changes mRNA
• transcription
• changes tRNA
• diff shape protein

Question 6

Describe how you could use hydrogen-carbonate indicator to investigate the
effect of light intensity on net gas exchange in a leaf.

Answer 6

• cover leaf with foil
• leaf in test tube with bung
• look for colour change after some time
• same volume of indicator and temp
• same species
• yellow = CO2 produced (respire)
• Purple = O2 produced
  (photosynthesis)