II – Reproduction: A.U sing DNA to Make Proteins: As You grow cells divide producing new cells. These cells become specialized organs and grow larger.

D- D- SexualSexual ReproductionReproduction:: Involves the joining of two special reproductive cells, one from each parent.

1- These sexsex cellscells or gametesgametes have half the number of chromosomes as the body cells.

2- GametesGametes are formed by a special type of cell division called meiosis.

3- 3- During sexual reproduction the sperm and egg cell join this is called fertilizationfertilization.

a-a- When they join they form one cell with a complete set of chromosomes.

E-E-Development of the Development of the Fertilized EggFertilized Egg: A Fertilized egg is called a zygote

1-Forms new identical cell through the process of mitosis.

2- This process (Differentiation) or cleavage continues forming more and more cells.

3- Sexual reproduction leads to variation in offspring.

F-F- Sexual Reproduction in Sexual Reproduction in PlantsPlants.

11-- The flowerflower is the reproductive organ in a plant.

2-2- Parts of a Flower

a-a-StamenStamen = male contains the antheranther which produces pollen

grain (male gamete) and the filamentfilament holds up the anther.

3-3- PistilPistil = female contains the

~StigmaStigma sticky to catch pollen,

~stylestyle tube leading to ovaries,

~ovariesovaries which contain ovules the eggs (ovum female gamete) of the flower.

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