Cell division: is at the heart of reprod. 2 types reprod- sexual (similar) and A sexual (same makeup). Fct of Asexual reprod: replacement of lost cells, repair of damaged cells. Features: mitosis, no genetic variation, fast, in gen larger numbers of offspring, no need for gametes(sex cells). Prokaryotes reprod by binary fission. Eukaryotes more complex, more genes, genes in nucleus, grouped in chromosomes. Chromosomes- DNA containing structures that carry the organism’s genes. Made up of chromatin- combination of uncoiled DNA and protein molec. DNA packing- successive levels of coiling of DNA & proteins results in highly condensed chromosomes. Mitosis- Chromosomes duplicates producing sister chromatids. Sister chromatids contain identical genes. The chromatids are joined together tightly at the centromere. Cell cycle-consists of 2 phases, interphase and mitotic phase. S-DNA synthase. Interphase- cells spends most time here(most common to see), cell performs normal fct., cell doubles everything in cytoplasm, chromosome duplication. Sequence: G1 cell grows in
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