护理入学考试生物练习卷（附答案）

What is the cytoplasm?

1. AThe fluid found only inside the nucleus
2. BThe jelly-like contents between the membrane and nucleus
3. CThe space between two neighbouring cells
4. DThe stiff outer layer of cellulose that surrounds a plant cell

What is a sister chromatid?

1. AA chromosome that is inherited from the mother only, never the father
2. BOne of two identical copies of a chromosome joined at the centromere
3. CA small ring of DNA found in bacteria
4. DOne of the two sex chromosomes

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

1. AOxygen
2. BNitrogen
3. CHydrogen
4. DCarbon dioxide

正常的人类卵细胞含有多少条染色体？

1. A92
2. B23
3. C22
4. D46

Why are stains such as iodine or methylene blue added to cells on a microscope slide?

1. ATo make the cells divide
2. BTo make the cells larger
3. CTo keep the cells alive for longer
4. DTo make structures easier to see

Why do the palisade cells near the top surface of a leaf contain many chloroplasts?

1. AThey store most of the plant's water for dry periods
2. BThey get the most light and do most of the photosynthesis
3. CThey carry sugars from the leaves down to the roots
4. DThey protect the leaf from insects and strong winds

为什么大多数细胞都很小？

1. A小细胞的表面积与体积之比高
2. B小细胞比大细胞含有更多的 DNA
3. C小细胞不需要氧气
4. D大细胞不能含有线粒体

A karyotype shows three copies of chromosome 21. Which condition does this indicate, and how many chromosomes does the person have?

1. ADown syndrome, with 47 chromosomes
2. BKlinefelter syndrome, with 45 chromosomes
3. CDown syndrome, with 45 chromosomes
4. DTurner syndrome, with 47 chromosomes