Moleclar Biology

Question 1

Steps in protein biosynthesis

Answer 1

1. DNA is copied to mRNA in the nucleus
2. mRNA goes from the nucleus to the cytoplasm
3. mRNA meets a ribosome
4. tRNA carries amino acids to the ribosome
5. Amino acids are linked together in a chain to make a protein.

Question 2

Steps in mitosis

Answer 2

1. Prophase
2. Metaphase
3. Anaphase
4. Telophase
   (5. Cytokinesis)

Question 3

Prophase

Answer 3

Chromatin (the spread-out form of DNA) condenses into chromosomes (the tightly-packed molecules of DNA that look like Xs).

Question 4

Metaphase

Answer 4

Chromosomes line up in the middle of the cell and spindle fibres attach to the centromeres of the chromosomes.

Question 5

Anaphase

Answer 5

The sister chromatids in each chromosome are ripped apart.

Question 6

Telophase

Answer 6

The chromosomes at each pole de-condense and nuclear envelopes form around each set.

Question 7

Cytokinesis

Answer 7

Splitting of the cell into two new daughter cells. The membrane comes down the middle and breaks the two new cells apart.