Asexual vs Sexual Reproduction

Sexual reproduction

Reproduction involving the fusion of male and female gametes, producing genetically different offspring

Asexual reproduction

Reproduction involving only one parent, producing genetically identical offspring (clones)

Gamete

A sex cell (sperm or egg) containing half the normal number of chromosomes

Fertilisation

The fusion of a male and female gamete to form a zygote

Zygote

A fertilised egg cell that divides by mitosis to form an embryo

Embryo

A developing organism formed after fertilisation and cell division

Testes

Produce sperm and testosterone

Scrotum

Holds testes outside the body to keep them cooler for sperm production

Sperm cells

Male gametes adapted with a tail for movement and many mitochondria for energy

Penis

Transfers sperm into the female reproductive system

Ovaries

Produce eggs and hormones (oestrogen and progesterone)

Oviduct (fallopian tube)

Where fertilisation usually occurs

Uterus

Where the embryo implants and develops

Uterus lining

Thickens to support a fertilised egg

Vagina

Receives penis and sperm during sexual intercourse

Oestrogen

Rebuilds and thickens the uterus lining; inhibits FSH; stimulates LH

Progesterone

Maintains the uterus lining; inhibits FSH and LH

FSH (Follicle-Stimulating Hormone)

Causes egg maturation in the ovary and stimulates oestrogen release

LH (Luteinising Hormone)

Triggers ovulation and formation of the corpus luteum

Ovulation

The release of an egg from the ovary

Placenta

Transfers oxygen, nutrients, and antibodies from mother to fetus and removes waste

Umbilical cord

Connects the fetus to the placenta

Amniotic fluid

Cushions the embryo, absorbs shock, allows movement, and maintains temperature

Secondary sexual characteristics

Physical changes during puberty that distinguish males and females

Oestrogen (secondary characteristics)

Causes breast development, wider hips, and regulation of the menstrual cycle

Testosterone (secondary characteristics)

Causes deeper voice, facial hair, muscle growth, and sperm production