Cell biology worksheet with answers

Which base pairs with adenine in DNA?

1. ACytosine
2. BGuanine
3. CThymine
4. DUracil

Which type of microscope can resolve the smallest structures, such as ribosomes?

1. AElectron microscope
2. BDissecting microscope
3. CMagnifying glass
4. DLight microscope

What is cytokinesis?

1. AThe breakdown of the nuclear envelope
2. BThe division of the cytoplasm into two daughter cells
3. CThe pairing of homologous chromosomes
4. DThe copying of DNA before division

What is crossing over during meiosis?

1. ASeparation of sister chromatids as they move to opposite poles in anaphase II
2. BFusion of two gametes
3. CCopying of DNA before division
4. DExchange of genetic material between homologous chromosomes in prophase I

Which molecules can cross a phospholipid bilayer most easily by simple diffusion?

1. ASmall non-polar molecules such as O₂ and CO₂
2. BProteins such as albumin
3. CLarge polar molecules such as glucose
4. DIons such as Na⁺ and K⁺

The Golgi apparatus mainly:

1. AReplicates DNA
2. BProduces ATP
3. CBreaks down old organelles and engulfed bacteria with enzymes
4. DModifies, sorts and packages proteins for transport

In Tay–Sachs disease, a ganglioside builds up in nerve cells because of a missing enzyme. In which organelle does the build-up occur?

1. AMitochondrion
2. BSmooth ER
3. CPeroxisome
4. DLysosome

Tumour suppressor genes such as p53 normally:

1. AProduce growth factors
2. BMake cells immortal
3. CSpeed up cell division so that damaged cells are quickly replaced
4. DStop the cell cycle or trigger apoptosis when DNA is damaged