1.1- division and differentiation in human cells Flashcards
what are somatic cells?
non-sex cells that make up all the cells in the human body other than gametes
4 things made up by somatic cells
smooth muscle cells
red blood cells
b lymphocytes
epithelial cells
how many chromosomes do somatic cells contain?
46 (23 homologous pairs) (diploid)
how do somatic cells divide and what into?
mitosis
divide into daughter cells which may then divide to form more cells
what does the division of somatic daughter cells result in?
increase in size of the body and its organs
what are germline cells?
cells that eventually leads to the formation of sex cells (gametes)
how many chromosomes do germline cells contain?
46 (23 homologous pairs) (diploid)
what happens when a germline cells nucleus divides by mitosis?
it maintains the diploid chromosome number
what types of nuclear division do germline cells undergo?
mitosis
meiosis
what is meiosis?
process that produces haploid gametes intended to fuse with another gamete to produce a zygote
process of meiosis
original germline cells contains 23 homologous pairs of chromosomes
division 1
homologous pairs of chromosomes separated and each cell contains 23 homologous chromosomes
division 2
chromosomes separated and 4 haploid cells are made each showing genetic variation
what cells do mitosis and meiosis take place in?
germline cells
summary of mitosis and meiosis
mitosis- germline stem cells divide and produce more germline cells
meiosis- produces haploid gametes
what is cellular differentiation?
process by which a cell expresses certain genes to produce proteins characteristic for that type of cell
what does cellular differentiation allow a cell to do?
carry out a specialised function