Reproduction in Animals
IGCSE Biology – 10th Grade
Academic Year: 2025/2026
Learning Objectives
• • Describe sexual and asexual reproduction in
animals.
• • Explain the structure and function of human
reproductive systems.
• • Understand fertilisation, pregnancy, and
birth.
• • Describe the hormonal regulation of the
menstrual cycle.
Asexual vs Sexual Reproduction
• • Asexual: One parent, identical offspring
(e.g., budding, binary fission).
• • Sexual: Two parents, genetic variation in
offspring.
• • Common in animals: sexual reproduction.
Male Reproductive System
• • Main parts: testes, scrotum, sperm duct,
urethra, penis.
• • Function: produce and deliver sperm.
Female Reproductive System
• • Main parts: ovaries, oviducts, uterus, cervix,
vagina.
• • Function: produce eggs, support fertilisation
and development.
Fertilisation and Development
• • Fertilisation: fusion of sperm and egg.
• • Zygote develops into embryo, then foetus in
uterus.
• • Placenta: exchange of nutrients and gases
between mother and baby.
The Menstrual Cycle
• • Cycle length: ~28 days.
• • Main hormones: oestrogen and
progesterone.
• • Stages: menstruation, ovulation, preparation
of uterus lining.
Summary
• • Animals reproduce mainly through sexual
reproduction.
• • Human reproduction involves specific
structures and hormonal control.
• • Fertilisation leads to the development of a
new organism.
• • The menstrual cycle prepares the body for
potential pregnancy.
Check Your Understanding
• 1. What is the difference between sexual and
asexual reproduction?
• 2. Name three parts of the male reproductive
system and their functions.
• 3. What is the role of the placenta during
pregnancy?
• 4. Explain what happens during ovulation.
• 5. Which hormones regulate the menstrual
cycle?