Reproductive Cells and The Menstrual Cycle

Function: To transport males DNA to the females egg so the DNA can combine.

Features:

Small

Long Tails (So they can swim to egg)

Lots of mitochondria in middle section for energy (From respiration) 

Acrosome at front where enzymes are stored (Needed to digest their way through the membrane of egg cell)

Contain haploid nucleus (One copy of each chromosome)

Function: To carry female DNA and nourish the developing embryo in early stages.

Features:

Contains nutrients in cytoplasm to feed embryo

Straight after fertilisation egg changes structure of membrane (To stop anymore sperm getting in)

Contains haploid nucleus

Day 1 - Bleeding starts. Uterus lining breaks down and is released (menstruation)

Stage 2 - Lining of uterus builds up again (Day 4-14) into thick spongy layer of blood vessels ready to recieve fertilised egg.

Stage 3 - Egg is released from ovary (Ovulation) at day 14.

Stage 4 - Lining maintained until day 28. If not fertilised lining breaks down.