Cell biology worksheet with answers

Which part of the cytoskeleton forms the mitotic spindle?

1. AActin filaments
2. BMicrotubules
3. CIntermediate filaments
4. DCollagen fibres

Which organelle produces most of the cell's ATP?

1. AGolgi apparatus
2. BMitochondrion
3. CLysosome
4. DRibosome

What is phagocytosis?

1. AThe release of proteins from the cell in membrane-bound vesicles
2. BThe movement of water across a membrane
3. CThe uptake of small ions through channels
4. DThe uptake of large particles by engulfing them in membrane

Which cell junction lets ions and small molecules pass directly between neighbouring cells?

1. ATight junction
2. BDesmosome
3. CAdherens junction
4. DGap junction

Which enzyme unwinds the DNA double helix during replication?

1. AHelicase
2. BDNA ligase
3. CPrimase
4. DDNA polymerase

The contractile ring that pinches an animal cell in two during cytokinesis is made of:

1. AActin and myosin
2. BCellulose fibres
3. CMicrotubules and kinesin
4. DKeratin filaments

A disease is passed from an affected mother to all her children but never from an affected father. Where is the mutation most likely located?

1. AOn an autosome, as a recessive trait
2. BOn the Y chromosome
3. COn the X chromosome, as a dominant trait
4. DIn mitochondrial DNA

With 23 chromosome pairs, how many different chromosome combinations can independent assortment alone produce in human gametes?

1. A2 × 23
2. B2²³ (about 8 million)
3. C46
4. D23²