护理入学考试生物练习卷（附答案）

DNA 等核酸的单体是什么？

1. A葡萄糖分子
2. B氨基酸
3. C核苷酸
4. D甘油分子

In an enzyme reaction, what is the substrate?

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

What is a heterotroph?

1. AAn organism that lives only in water
2. BAn organism with no cells
3. CAn organism that gets its food from other organisms
4. DAn organism that makes its own food by photosynthesis

什么决定蛋白质的形状和功能？

1. A细胞中葡萄糖的量
2. B其氨基酸的序列
3. C膜中脂肪酸的顺序
4. D其所携带的磷酸基团的数量

In gel electrophoresis, why does DNA move towards the positive electrode?

1. ADNA has a negative charge from its phosphate groups
2. BDNA is pulled by gravity through the gel
3. CDNA has no charge and moves at random
4. DDNA has a positive charge from the nitrogen bases it contains

Human adult height varies across a smooth, continuous range rather than falling into a few separate groups. What is the best explanation?

1. AIt is an X-linked recessive trait
2. BIt is controlled by one gene with two alleles and full dominance
3. CIt is controlled only by the environment
4. DIt is controlled by many genes and also affected by environment

Which parent's gamete decides the biological sex of a human baby, and why?

1. AThe father's, because a sperm carries either an X or a Y
2. BThe mother's, because she gives two X chromosomes
3. CBoth equally, because each gives one Y chromosome
4. DThe mother's, because an egg carries either an X or a Y

Cyanide stops mitochondria from making ATP. Which process in the affected cells would stop first?

1. APumping of Na⁺ and K⁺ by the sodium-potassium pump
2. BOsmosis of water across the membrane
3. CFacilitated diffusion of glucose down its gradient
4. DSimple diffusion of oxygen into the cell