Cell biology worksheet with answers

Which part of the cytoskeleton forms the mitotic spindle?

1. AIntermediate filaments
2. BActin filaments
3. CCollagen fibres
4. DMicrotubules

Which sugar is found in DNA?

1. ADeoxyribose
2. BFructose
3. CGlucose
4. DRibose

A haploid cell contains:

1. AOne set of chromosomes
2. BTwo sets of chromosomes
3. CNo chromosomes
4. DFour sets of chromosomes

How do large proteins such as transcription factors enter the nucleus?

1. ABy diffusing freely through the nuclear membrane lipids
2. BBy exocytosis from the endoplasmic reticulum
3. CThey are made inside the nucleus by nuclear ribosomes, so they never enter
4. DThrough nuclear pore complexes, guided by a nuclear localisation signal

Which tag added in the Golgi sends enzymes to the lysosomes?

1. AMannose-6-phosphate
2. BA nuclear localisation signal
3. CA KDEL sequence
4. DUbiquitin

What role does cholesterol play in animal cell membranes?

1. AIt helps keep membrane fluidity stable across temperatures
2. BIt makes the membrane completely rigid at every temperature
3. CIt is the main carrier of glucose
4. DIt forms channels for ions

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. APeroxisome
2. BMitochondrion
3. CSmooth ER
4. DLysosome

Some antibiotics, such as tetracyclines, block bacterial protein synthesis with little effect on human cytoplasmic ribosomes. Why?

1. ABacterial 70S ribosomes differ in structure from eukaryotic 80S ribosomes
2. BHuman cells do not make proteins
3. CBacteria use DNA instead of mRNA as the template for translation on ribosomes
4. DHuman ribosomes are inside the nucleus