Meiosis/Mitosis Flashcards
What is the difference between mitosis and meiosis?
the crossover that occurs in prophase 1
What is synapsis?
the fusion of chromosome pairs at the start of meiosis.
What is chiasmata?
site of crossing over
What is nondisjunction?
An error in cell division that causes homologous chromosomes or sister chromatids to move to the same side of the dividing cell
(leads to abnormal numbers of chromosomes in daughter cells)
What is spermatogenesis
the production of sperm in the testes
- starts with a diploid cell called a spermatogonium
- at puberty, spermatogonia reproduced by mitosis undergo meiosis to form 4 haploid cells
- after meiosis the cells undergo a final developmental stage where they develop into mature sperm
What is oogenesis
the production of egg cells that occurs in the ovaries
- starts with an Oogonium (diploid cell) that develops into oocytes
- before birth, the oocytes reproduce by mitosis and meiosis but stop at prophase 1
- at puberty, hormones cause oogenesis to continue and during each menstrual cycle one oocyte completes meiosis 1 and leaves the ovary (ovulation)
*Oogenesis involves in the cytoplasm dividing unequally so only 1 egg is produced
Explain the difference between mitosis and cytokinesis
mitosis is a type of cell division in which a whole cell divides
cytokinesis is one of the steps of mitosis in which the cytoplasm of the cell divides
What phase of mitosis do the cells need to be in to get a viable karyotype image? Why not interphase?
To obtain a viable karyotype image, cells need to be in the metaphase stage of mitosis. Metaphase is the stage where chromosomes are most condensed and aligned along the metaphase plate, making them easier to observe and analyze under a microscope.
Interphase is not suitable for obtaining a karyotype image because during interphase, the chromosomes are in their least condensed state, and individual chromosomes are not distinguishable. Instead, they appear as long, thread-like structures within the nucleus.
