Biology for nursing entrance exams worksheet with answers

Which organelle breaks down fatty acids and hydrogen peroxide?

1. APeroxisome
2. BRibosome
3. CChloroplast
4. DCentriole

Which bonds hold the two strands of a DNA double helix together?

1. AHydrogen bonds between the bases
2. BPeptide bonds between the sugars
3. CDisulfide bonds between the bases
4. DIonic bonds between the phosphates

What is a gene?

1. AA complete set of all the chromosomes of a cell
2. BA type of cell that carries hereditary traits
3. CA protein that copies DNA before cell division
4. DA section of DNA that codes for a product such as a protein

What happens when a ribosome reaches a stop codon on the mRNA?

1. ATranslation ends and the protein is released
2. BThe ribosome goes back to the start codon
3. CA special amino acid is added to end the chain
4. DThe mRNA is copied back into DNA

Researchers randomly assign patients to receive either a new wound dressing or the standard dressing and compare healing times. What type of study is this?

1. AAn observational study
2. BA controlled experiment
3. CA survey
4. DA case report

Which kind of mutation can be passed on to a person's children?

1. AA mutation in a white blood cell during infection
2. BA mutation in a cell that forms eggs or sperm
3. CA mutation in a liver cell caused by alcohol
4. DA mutation in a skin cell caused by sunlight

Parts of a protein chain coil into alpha helices and fold into beta sheets, held by hydrogen bonds. Which level of protein structure is this?

1. ASecondary structure
2. BQuaternary structure
3. CTertiary structure
4. DPrimary structure

Bacteria from hot springs have enzymes that work best at about 80 °C, while most human enzymes work best near 37 °C. What is the best explanation?

1. ATheir enzymes do not have an active site, so heat cannot affect them
2. BHigh temperature never affects any enzyme
3. CTheir enzymes have structures that stay stable at high temperatures
4. DTheir enzymes are made of lipids, not proteins