Биология для вступительных экзаменов на сестринские программы: лист заданий с ответами

Which gas do plants take in from the air for photosynthesis?

1. ACarbon dioxide
2. BHydrogen
3. COxygen
4. DNitrogen

In genetics, what is a carrier?

1. AA person who has a dominant disorder
2. BA person with two recessive alleles who has the disorder
3. CA person with one recessive allele for a disorder but no symptoms
4. DA person who has lost both alleles for the gene, so shows no trait

Сколько хромосом в типичной клетке тела человека?

1. A46
2. B44
3. C92
4. D23

Почему очень высокая температура останавливает работу большинства ферментов?

1. AПод действием тепла фермент мгновенно распадается на аминокислоты
2. BФермент движется слишком медленно, чтобы встретить субстрат
3. CСубстрат превращается в другой фермент
4. DФермент денатурирует: его активный центр меняет форму

What is the job of the checkpoints in the cell cycle?

1. ATo copy the DNA a second time before mitosis
2. BTo join the two daughter cells back together
3. CTo stop the cycle if the DNA is damaged or the cell is not ready
4. DTo speed up division whenever the cell is short of nutrients or space

What happens to an enzyme after it has catalysed a reaction?

1. AIt is broken down into amino acids
2. BIt is released unchanged and can be used again
3. CIt becomes part of the product and leaves with it
4. DIt changes into the substrate

Potato cylinders are placed in sugar solutions of different strengths. They gain mass in weak solutions, lose mass in strong ones and show no change at 0,3 mol/L. What can be concluded?

1. APotato cells are always hypertonic to sugar solutions
2. BThe potato cells contain no water at all
3. CThe potato cells have a solute concentration of about 0,3 mol/L
4. DSugar enters the cells only by active transport, not by diffusion

Five recovery times in days are 5, 6, 6, 7 and 30. Which value best describes a typical recovery time, and why?

1. AThe range of 25, because it shows the spread
2. BThe median of 6, because the outlier pulls the mean up
3. CThe mean of 10,8, because it uses every value
4. DThe maximum of 30, because it shows the worst case