Cell biology worksheet with answers

What does meiosis produce from one diploid cell?

1. AFour genetically identical haploid cells
2. BTwo genetically different diploid cells
3. CFour genetically different haploid cells
4. DTwo genetically identical diploid cells

How do enzymes speed up chemical reactions?

1. AThey are used up in the reaction
2. BThey change the reaction's final equilibrium
3. CThey lower the activation energy
4. DThey raise the temperature of the cell

Which structure is found in plant cells but not in animal cells?

1. AMitochondria
2. BCell wall
3. CRibosomes
4. DCell membrane

The Golgi apparatus mainly:

1. AModifies, sorts and packages proteins for transport
2. BReplicates DNA
3. CProduces ATP
4. DBreaks down old organelles and engulfed bacteria with enzymes

A competitive inhibitor binds the active site of an enzyme. What can overcome its effect?

1. ARaising the substrate concentration
2. BRaising the inhibitor concentration
3. CRemoving the enzyme's cofactor
4. DLowering the temperature to 0 °C

Active transport differs from facilitated diffusion because it:

1. AOnly moves water
2. BMoves substances down their gradient faster by using carrier proteins
3. CNeeds no proteins
4. DUses energy to move substances against their concentration gradient

Bacteria moved to a much colder environment change the fatty acids in their membranes. Which change keeps the membrane fluid?

1. AFewer membrane proteins
2. BMore unsaturated fatty acids
3. CMore saturated fatty acids
4. DLonger fatty acid tails

A mutation in the lac repressor stops it binding to the operator. What is the result?

1. AThe lac genes are expressed only when glucose is present in the medium
2. BThe bacteria can no longer take up glucose
3. CThe lac genes are expressed all the time, even without lactose
4. DThe lac genes can never be expressed