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

Где находится большая часть ДНК эукариотической клетки?

1. AВ клеточной стенке
2. BВ клеточной мембране
3. CВ ядре
4. DВ лизосомах

What is the pH of pure water at 25 °C?

1. A14
2. B0
3. C1
4. D7

Что из перечисленного является грибом?

1. AВирус гриппа
2. BАмёба
3. CEscherichia coli
4. DДрожжи

What is a chromosomal translocation?

1. AOne DNA base is replaced by another base
2. BA piece of a chromosome is copied twice and stays in the same place
3. CA piece of a chromosome is flipped around in place
4. DA piece of one chromosome attaches to a non-matching chromosome

Why are G–C base pairs held together more strongly than A–T pairs?

1. AA–T pairs are found only in RNA
2. BG and C are both purines, so they fit more tightly
3. CG–C pairs form three hydrogen bonds, and A–T pairs form two
4. DG–C pairs are joined by strong covalent bonds instead of hydrogen bonds

Матричная цепь ДНК читается как T-A-C. Каков соответствующий кодон мРНК?

1. AA-U-G
2. BA-T-G
3. CU-T-G
4. DT-A-C

HIV infects and destroys helper T cells. Why do people with untreated advanced HIV get infections that healthy people rarely get?

1. ATheir immune response is too weak to control normally harmless microbes
2. BHelper T cells make the antibiotics that the body needs to fight infection
3. CHIV kills the normal flora of the skin and gut
4. DThe virus turns harmless microbes into pathogens

Two populations of one species live on separate islands for many thousands of years. When brought together, they can no longer interbreed. What has happened?

1. AHybrid vigour from crossbreeding
2. BArtificial selection by humans
3. CSpeciation after geographic isolation
4. DHomeostasis in both populations