Cell Division Flashcards
Ch 14
Definition of cell continuity?
means that all cells develop from pre-existing cells.
What are chromosomes?
are coiled threads of DNA and protein.
Humans have how many chromosomes in each body cell?
46.
Discuss chromosomes when a cell is not dividing?
they exist as long, thin threads called chromatin.
At cell division, chromatin…?
contracts to form a number of clearly distinguishable chromosomes.
What’s a gene?
a section of DNA that contains the instructions for the formation of a protein.
Definition of a haploid cell?
has one set of chromosomes.
Definition of diploid cell?
has two sets of chromosomes.
Haploid is symbolised by what letter?
n.
Diploid is symbolised as what?
2n.
What’s a homologous pair?
is two chromosomes of similar size with the same sequence of genes.
The cell cycle describes what?
the life cycle of a cell.
Definition of interphase?
state of non division.
What’s the longest phase in the cell cycle?
interphase.
Interphase accounts for over what % of the cycle?
90%.
Name 4 things that happen in interphase?
- photosynthesis,
- respiration,
- DNA replication,
- protein synthesis.
Definition of mitosis?
cell/nuclear division, forming two identical (daughter) cells.
What’s function of mitosis in unicellular organisms?
reproduction.
What’s function of mitosis in multicellular organisms?
growth/repair of tissue.
Name 4 human cells not produced by mitosis?
- sperm,
- egg,
- sex cell,
- gamete.
What is cancer?
uncontrolled mitosis.
What does benign mean?
kind.
What happens in a benign tumour?
the cells stop dividing after some time.
Are benign tumours life threatening? Why/why not?
no as they don’t invade other tissues.