Reproduction & Development Topic 4 Reproduction & Development

Topic 4 Vocabulary on p 60 Gamete, recombination, differentiation,zygote, clone Types of reproduction: Asexual Sexual

Topic 4 Examples of asexual reproduction

Topic 4 Cloning Same end result of asexual repro.

Topic 4 Mitosis- DNA must replicate PRIOR Identical One division Diploid  diploid Essential for growth, development, repair, etc. Plant cells form cell plate= cell wall, animal cells for cleavage furrow= pinches in . Meiosis- DNA must replicate PRIOR Source of variation Produces gametes with haploid # (half) Two divisions Crossing over=variety Non-disjunction= failure to separate Spermatogenesis 14 Oogenesis 11 viable +3 polar bodies

Topic 4 Zygote Formation Haploid gametes unite or fuse The male gamete is mobile, the female is not. Recombination – refers to combining of genetic material from both sources. Differentiation Cells of an organism have the SAME DNA but not all the genes are expressed in all cells… early in development differentiation occurs which initiates this/gene expression.

Topic 4 Human Reproduction Hormones produced in brain and reproductive organs(gonads) interact with certain tissues b/c of receptor molecules found on the cell membranes of those tissues. Hormones regulate reproductive cycles.

Topic 4 Female reproductive system: Ovaries (gonads) Fallopian tubes or Oviduct Uterus Placenta- temporary organ of the fetus Umbilical cord Vagina/birth canal Gestation= time of pregnancy from conception/fertilization till birth: development(mitosis) crucial that proper pre-natal care be taken during first few months especially b/c of organ development Zygoteembryofetusbaby Labor & delivery= positive feedback

Topic 4 Male reproductive system Testes (gonads) Scrotum Penis

Topic 4 Applications of technology in reproduction: IV fertilization Hormone therapy Vasectomy Tubal ligation Pre-natal screening: amniocentesis, karyotyping, etc