B2 - Cell Division Flashcards
How many chromosomes does the nucleus contain?
46 (23 pairs of) chromosomes
Why do organisms need new cells?
To grow, to replace worn out cells, to repair damaged tissue
What is a gene?
A gene is a small packet of information that controls a characteristic, or part of a characteristic, of your body.
What are the three stages of the cell cycle?
1) Interphase
2) Mitosis
3) Cytokinesis
What happens in interphase?
The cells grow and they replicate their DNA in preparation for division.
What happens in mitosis?
One set of chromosomes is pulled up to each end of the dividing cell and the nucleus divides.
What happens in Cytokinesis?
The cytoplasm and the cell membranes divide to produce two identical daughter cells
What is an embryonic stem cell?
They are stem cells that have been removed from the embryo and they can differentiate into any cell type
What is an adult stem cell?
They can only differentiate into related cell types only.
Why are chromosomes arranged in pairs?
Because one chromosome is given by each parent to make a pair, they each give 23 to make 23 pairs.
What are the potential risks of stem cell research?
Mutations have been observed in the stem cells, and some have been observed to behave like cancer, the uncontrollable growth causes a tumour to form.
What are the ethical concerns with stem cell research?
the research is unethical, because deriving the stem cells destroys the blastocyst, an unimplanted human embryo at the sixth to eighth day of development
