Summary
Sexual reproduction in humans involves the fusion of male and female gametes, resulting in genetically diverse offspring. It requires two parents and includes processes such as fertilization, gestation, and birth.
- Gamete — a sex cell with a haploid nucleus. Example: Sperm and ova are gametes.
- Zygote — a fertilized egg cell with a diploid nucleus. Example: Formed when sperm and ovum nuclei fuse.
- Placenta — an organ that facilitates nutrient exchange between mother and fetus. Example: Transfers oxygen and nutrients to the fetus.
- Umbilical Cord — connects the fetus to the placenta. Example: Carries nutrients and removes waste from the fetus.
- Amniotic Sac — a fluid-filled sac that cushions the fetus. Example: Protects the fetus from physical shocks.
Exam Tips
Key Definitions to Remember
- Gamete: A sex cell with a haploid nucleus.
- Zygote: A fertilized egg cell with a diploid nucleus.
- Placenta: An organ for nutrient exchange between mother and fetus.
Common Confusions
- Mixing up the roles of the placenta and umbilical cord.
- Confusing gametes with normal body cells.
Typical Exam Questions
- What is the role of the placenta? It facilitates nutrient and waste exchange between mother and fetus.
- How does fertilization occur in humans? It occurs when a sperm cell fuses with an ovum.
- What is the function of the amniotic sac? It cushions and protects the fetus during development.
What Examiners Usually Test
- Understanding of the roles of different reproductive organs.
- The process and significance of fertilization.
- Differences between gametes and normal body cells.