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 The life process by which an organism produces new individuals of the same kind.  This is essential for the survival of the species.

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Presentation on theme: " The life process by which an organism produces new individuals of the same kind.  This is essential for the survival of the species."— Presentation transcript:

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5  The life process by which an organism produces new individuals of the same kind.  This is essential for the survival of the species

6  Asexual Reproduction  Involves ________ parent and results in one or more offspring that are genetically _________ to that parent.  Cells reproduce by Mitosis one identical

7  A process where a cell divides and creates two daughter cells which are identical to the parent  Cell Division happens by series of phases ▪ Interphase, prophase, metaphase,anaphase, and telophase (cytokinesis) ▪ I.P.M.A.T.(C).

8 interphaseprophase metaphaseanaphasetelophase cytokinesis I.P.M.A.T.C. P lease M ake A nother T wo C ells

9 nucleus cell DNA in chromosomes nucleus cell duplicated chromosomes chromosomes in cell 4 single-stranded chromosomes duplicated chromosomes 4 double-stranded chromosomes

10  Stage 1: cell copies DNA nucleus cell DNA Copy DNA! INTERPHASE

11  Stage 2: DNA winds into chromosomes  Nuclear membrane disappears  Spindle Fibers/ Centrioles appear nucleus cell duplicated chromosomes Wind up! PROPHASE

12 double-stranded human chromosomes ready for mitosis

13  Stage 3: Chromosomes line up in middle  attached to protein “cables” that will help them move duplicated chromosomes lined up in middle of cell Line up! METAPHASE

14  Stage 4: Chromosomes separate  start moving to opposite ends chromosomes split & move to opposite ends Separate! ANAPHASE

15  Stage 5: Cell starts to divide  Two nuclei  Chromosomes unwind Divide! TELOPHASE

16  Stage 6: DNA unwinds again  cells separate completely (cleavage furrow)  now they can do their every day jobs Bye Bye! CYTOKINESIS

17 Biology is the only subject in which multiplication is the same thing as division…

18 Binary Fission  The cell splits into two identical cells, each containing an exact copy of the original cell's DNA. Nucleus and Cytoplasm divide EQUALLY!

19 Budding- where the daughter cell grows out of the parent and gradually increases in size. Yeast cells Hydra Nucleus divides equally Cytoplasm divides unequally

20 Spores  Reproductive cell that contains a nucleus and a small amount of cytoplasm  Spores are highly resistant to heat  Spores are capable of growing into a new organism when conditions allow  Produced by bread mold, mushrooms, mosses and ferns

21 Regeneration  Development of a new organism from part of a parent  Whole organisms are produced – Starfish!  Replacement of lost body part

22 Vegetative Propagation  Part of a plant (root, stem, leaves) grows into a new plant  Seedless fruits & vegetables  Commonly used by farmers = quick, easy & successful!

23  Offspring receive half of their genes from one parent and half from the other parent  The genes are carried on chromosomes in sex cells known as gametes  Male gamete is the sperm cell  Female gamete is the ovum (egg)

24  Joining of 2 sex cells (egg & sperm)  Do we make egg & sperm by mitosis? 46 + 92 eggspermzygote What if we did, then…. Doesn’t work! No!

25  Gametes are formed by Meiosis Meiosis (reduction division)  In series of divisions the number of chromosomes is reduced by half

26  46 chromosomes to 23 chromosomes  half the number of chromosomes 23 46 egg sperm 46 meiosis haploiddiploid

27  Fertilization  Two gametes (Ovum and Sperm) join to create an offspring  Variation  Each offspring gets a unique combination of genes, therefore they are not identical to their parents or siblings.

28 Meiosis (reduction division)  Spermatogenesis: Creates 4 sperm cells  Oogenesis: Creates 1 ovum and 3 polar bodies

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31 mitosis zygote 23 46 egg sperm 46 meiosis 46 23 fertilization mitosis & development meiosis  fertilization  mitosis + development 46 gametes

32 Meiosis to make gametes  sperm & egg Mitosis to make copies of cells  growth  repair  Development  replacement

33  Consistency over time  meiosis keeps chromosome number same from generation to generation from Mom from Dad offspring DadMom

34  Change over time  meiosis introduces genetic variation ▪ gametes of offspring do not have same genes as gametes from parents ▪ new combinations of traits from Mom from Dad new gametes made by offspring offspring We ’ re mixing things up here! variation

35 Crossing Over – Trading DNA!  During prophase 1, sister chromatids intertwine  homologous pairs swap pieces of chromosome ▪ DNA breaks & re-attaches tetrad prophase 1

36 Sexual reproduction allows us to maintain both genetic similarity & differences. Baldwin brothers Jonas Brothers Martin & Charlie Sheen, Emilio Estevez

37  The nucleus is taken from parent with a complete set of genetic information  Injected into an egg cell which has had its nucleus removed

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39  The egg is implanted in a surrogate mother  Result is an organism which is 100% genetically identical to parent

40 Many more to come… Too many to list…


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