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

Сколько хромосом в типичной клетке тела человека?

1. A92
2. B23
3. C44
4. D46

What does transfer RNA (tRNA) do?

1. AIt joins two DNA strands together
2. BIt brings amino acids to the ribosome
3. CIt copies DNA in the nucleus
4. DIt carries the code out of the nucleus

In an enzyme reaction, what is the substrate?

1. AThe gene that codes for the enzyme
2. BThe substance that the enzyme acts on
3. CThe part of the enzyme that changes shape
4. DThe product released at the end

Что общего у крахмала, гликогена и целлюлозы?

1. AЭто полисахариды, состоящие из единиц глюкозы
2. BЭто белки, состоящие из аминокислот
3. CЭто нуклеиновые кислоты, хранящие наследственную информацию
4. DЭто липиды, запасающие энергию

What happens during telophase of mitosis?

1. AA nuclear envelope forms around each set of chromosomes
2. BThe chromosomes line up across the middle of the cell
3. CThe DNA is copied for the next division
4. DThe sister chromatids are pulled apart

In evolution, what does an organism's fitness mean?

1. AHow large the organism grows
2. BHow long the organism lives
3. CHow strong and fast the organism is compared with others
4. DHow many offspring it leaves that survive and reproduce

Bacteria in a closed flask grow quickly at first, but the population then stops increasing. What is the main reason?

1. ANutrients run out and waste products build up
2. BThe flask becomes too cold for growth
3. CThe bacteria change into viruses after many divisions
4. DThe bacteria stop dividing once they reach adult size

Bacteria from hot springs have enzymes that work best at about 80 °C, while most human enzymes work best near 37 °C. What is the best explanation?

1. AHigh temperature never affects any enzyme
2. BTheir enzymes do not have an active site, so heat cannot affect them
3. CTheir enzymes have structures that stay stable at high temperatures
4. DTheir enzymes are made of lipids, not proteins