AQA A LEVEL MATHEMATICS PAPER 1
MARK SCHEME EXAMINATION TEST
> Function = Holds/ stores genetic information for polypeptide
production. DNA Replication and the production of mRNA.
⩥ Them the polymers that form the cells walls of plants and fungal.
Answer: Plant cell walls = Cellulose
Fungal cell walls = chitin
⩥ Suggest one reason the scientists used biomass instead of the number
of individuals of each plant species when collecting data to measure
diversity.. Answer: > Individual organisms could not be identified/
separated
⩥ Clostridium difficile is a bacterial species that causes disease in
humans. Antibiotic-resistant strains of C.difficile have become a
common cause of infection acquired when in hospital. Explain how the
use of antibiotic has led to antibiotic resistant strains of bacteria
becoming a common cause of infection acquired when in the hospital..
Answer: 1. Some bacteria have alleles for resistance.
2. Exposure to antibiotic is the selection pressure.
3. More antibiotics used in hospitals in comparison to elsewhere.
, ⩥ Describe how the scientists could use aseptic techniques to transfer
0.3cm of C.difficile in liquid culture from a bottle onto an agar plate.k.
Answer: 1.Wash hands with soap
2. Use sterile pipettes/ syringe to transfer bacteria
3. Remove bottle lid and flame neck of bottle.
4. Lift lid of agar plate at an angle
5. Work close to upward air movement
6. Use sterile spreader
7. Place pipettes/ spreader into disinfectant
⩥ Use Figure 2 to evaluate whether more trehalose in the diet could be a
factor in the increased number of antibiotic-resistant C.difficile
infections. Answer: For :
1. Resistant bacteria grow faster with trehalose
2.So resistant bacteria are likely to increase in frequency in the
population.
3. Restistant bacteria are likely to outcompete non-resistant bacteria.
Against:
4. In a laboratory not in people
5. Other disaccharides in the diet might affect bacteria
6. Other bacterial species in the body might affect bacteria
MARK SCHEME EXAMINATION TEST
> Function = Holds/ stores genetic information for polypeptide
production. DNA Replication and the production of mRNA.
⩥ Them the polymers that form the cells walls of plants and fungal.
Answer: Plant cell walls = Cellulose
Fungal cell walls = chitin
⩥ Suggest one reason the scientists used biomass instead of the number
of individuals of each plant species when collecting data to measure
diversity.. Answer: > Individual organisms could not be identified/
separated
⩥ Clostridium difficile is a bacterial species that causes disease in
humans. Antibiotic-resistant strains of C.difficile have become a
common cause of infection acquired when in hospital. Explain how the
use of antibiotic has led to antibiotic resistant strains of bacteria
becoming a common cause of infection acquired when in the hospital..
Answer: 1. Some bacteria have alleles for resistance.
2. Exposure to antibiotic is the selection pressure.
3. More antibiotics used in hospitals in comparison to elsewhere.
, ⩥ Describe how the scientists could use aseptic techniques to transfer
0.3cm of C.difficile in liquid culture from a bottle onto an agar plate.k.
Answer: 1.Wash hands with soap
2. Use sterile pipettes/ syringe to transfer bacteria
3. Remove bottle lid and flame neck of bottle.
4. Lift lid of agar plate at an angle
5. Work close to upward air movement
6. Use sterile spreader
7. Place pipettes/ spreader into disinfectant
⩥ Use Figure 2 to evaluate whether more trehalose in the diet could be a
factor in the increased number of antibiotic-resistant C.difficile
infections. Answer: For :
1. Resistant bacteria grow faster with trehalose
2.So resistant bacteria are likely to increase in frequency in the
population.
3. Restistant bacteria are likely to outcompete non-resistant bacteria.
Against:
4. In a laboratory not in people
5. Other disaccharides in the diet might affect bacteria
6. Other bacterial species in the body might affect bacteria