护理入学考试生物练习卷（附答案）

What are restriction enzymes?

1. AEnzymes that join amino acids into proteins
2. BEnzymes that copy RNA into DNA
3. CEnzymes that digest fats in the intestine
4. DEnzymes that cut DNA at specific base sequences

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

Which definition of a species is most often used for animals?

1. AAll of the different organisms that live together in one area
2. BAll the animals that eat the same food
3. CA group that can interbreed and have fertile offspring
4. DAny organisms that look alike

What is the role of cholesterol in animal cell membranes?

1. AIt carries glucose molecules across the membrane into the cell
2. BIt stores the cell's genetic information
3. CIt forms a rigid wall around the cell
4. DIt keeps membrane fluidity stable as temperature changes

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

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

What do nitrogen-fixing bacteria do?

1. AThey turn carbon dioxide into sugar
2. BThey convert nitrogen gas into compounds that plants can use
3. CThey release nitrogen gas from dead organisms into the air
4. DThey break down proteins into glucose

哪种图表最适合显示患者体温在 24 小时内的变化？

1. A食物网
2. B庞尼特方格
3. C折线图
4. D饼图

A patient breathes very slowly, so carbon dioxide builds up in the blood. What happens to the blood pH, and why?

1. AIt rises, because CO₂ removes hydrogen ions
2. BIt rises, because CO₂ is a base
3. CIt stays the same, because CO₂ does not dissolve in blood
4. DIt falls, because CO₂ forms carbonic acid in the blood