genetic information is copied and passed on to daughter cells Flashcards
(22 cards)
cell division
process whereby a cell splits to form daughter cells
what are the two types of cell division?
mitosis and meiosis
what characteristic daughter cells does mitosis produce?
mitosis produces two diploid daughter cells that are genetically identical to each other and to the parent cell. this provides genetic stability
what characteristic daughter cells does meiosis produce?
meiosis produces four haploid daughter cells that are genetically different to each other and to the original parent cell
what are the daughter cells produced in meiosis used for?
the daughter cells formed in meiosis are used to produce gametes - sex cells used for sexual reproduction
what processes occur during interphase?
during interphase - DNA replicates, protein synthesis occurs, ATP is synthesised and organelles are produced
what are the four stages of mitosis?
prophase, metaphase, anaphase and telophase
what is a tumour?
an abnormal mass of tissues
what is interphase?
interphase is the longest stage of the eukaryotic cell cycle. cells grow and synthesise new organelles, proteins and DNA in preparation for mitosis
what is mitosis?
mitosis is a form of cell division. it produces two genetically identical diploid daughter cells
why is mitosis important?
mitosis is important for the growth of tissue and repair/replacement of cells
what is the prophase of mitosis?
nuclear envelope breaks down, chromosomes condense, centrioles move to opposite poles of the cell
what is the metaphase?
sister chromosomes line up at the equator, centromeres attach to the spindle fibres
what is the anaphase?
sister chromatids separated and pulled to opposite poles
what is the telephase?
nuclear envelop reforms, spindle fibres break down, chromosomes uncoil
what are sister chromatids?
sister chromatids are a pair of identical chromatids formed by DNA replication, joined by a centromere
what is cytokinesis?
the division of the cytoplasm at the end of mitosis to produce two new daughter cells
mitosis in animal cells
occurs in most tissues
before mitosis cell becomes rounded
involves centrioles
involves micro filaments
spindle fibres disappear prior to cytokinesis
mitosis in plant cells
occurs in meristematic cells only
cell does not change shape
no centrioles involved
no microfilaments involved
some spindle fibres remain during cytokinesis
what may unrestricted mitosis lead to?
cancerous growths
what is meiosis?
form of cell division that produces four genetically different daughter cells (gametes) with a haploid number of chromosomes which involves two divisions
what is the significance of meiosis in reproduction?
creates genetic variation