Organelles and the nucleus
Answers are for parents and teachers.
1
Compare a mitochondrion and a chloroplast on three features.
Both are double-membrane, have their own DNA and divide; the mitochondrion makes ATP, the chloroplast photosynthesises.
2
How many chromosomes does an onion (2n = 16) gamete have?
8
3
Why do leaves turn yellow in autumn? Explain from the point of view of plastids.
Chlorophyll breaks down and the colour of carotenoid-containing plastids shows.
4
List the parts of the nucleus and write the function of each in one sentence.
Envelope: separates; karyoplasm: medium; chromatin: holds DNA; nucleolus: makes ribosomes.
5
What does it mean that the human karyotype has 46 chromosomes?
23 pairs of homologous chromosomes: 23 from the father and 23 from the mother.