4 daughter cells not identical to parent cells(2n possible combinations of genes). Each new cell has the potential to join with another haploid cell to produce a diploid cell with a complete set of chromosomes. Reduces the chromosome number by half in new cells. One division, 2 daughter cells, daughter cells identical to parent cells Asexual reproduction Production of offspring from one parent Meiosis Occurs during formation of gametes, which are haploid reproductive cells. Occurs in organism undergoing growth, development, repair, or asexual reproduction. Two types of division: mitosis and meiosis Mitosis Results in new cells with genetic material that is identical to the genetic material of the original cell. A new cell wall forms around the new membrane and divides the cell into two new identical haploid cells Eukaryotic cell division Both cytoplasm and nucleus divide. Growing cell membrane pushes inward and constrict towards the center. Cell grows until it reaches approximately twice cell size. New cell meme ran develop between two DNA. DNA is copied resulting in two identical chromosomes attached inside cell membrane. Prokaryotic take cell division take place in process called binary fission Binary fission Division of prokaryotic cell in two offspring cells. DNA is circular and attached in cell membrane. DNA not coiled around proteins to form chromosomes. Cell division Aka cell reproduction is the process which cells produce offspring cells Prokaryotic have cell walls but lack nuclei and meme ran bound organelles. If reproductive cells were diploid, new cell would be too many chromosomes and not functional. When sperm cell(1n) and egg cell(1n) combine to create 1st new cell it becomes a diploid (2n). Thus, haploid have only one Autosome of each homologous pair and one sex chromosome (23 total). have half the number of chromosomes present in diploid cells. 46 chromosomes- 22 pairs of homologous autosomes and 2 sex chromosomes Haploid Sperm and egg cells. All human cells except reproductive cells (sperm and egg cells) are normally diploid. Have two sex chromosomes in animals and human. Have two autosomes for each homologous pair. XX: female Diploid Cells having two sets of chromosomes. 22 homologous pairs of autosomes and 2 sex chromosomes (XY: male. Homologous are the same size and shape and carry genes for the same traits Karyotype A photomicrograph of the chromosomes in a normal dividing cell found in human. Two copies of each Autosome are called homologous chromosomes or homologues. An organism receives one copy of each Autosome from each parent. Two of 26 human chromosome are sex chromosomes, remaining 44 chromosomes are autosomes Homologous chromosomes Every cell of organism produced by sexual reproduction has two copies of each Autosome. Autosome All the other chromosomes in an organism. Sex chromosomes Chromosomes that determine the sex of an organism and may also carry genes for other characteristics.
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