Table of contents

1. Introduction to Anatomy & Physiology5h 43m
2. Cell Chemistry & Cell Components12h 36m
3. Energy & Cell Processes10h 6m
4. Tissues & Histology10h 3m
5. Integumentary System2h 20m
6. Bones & Skeletal Tissue2h 16m
7. The Skeletal System2h 35m
8. Joints2h 17m
9. Muscle Tissue2h 33m
10. Muscles1h 11m
11. Nervous Tissue and Nervous System1h 35m
12. The Central Nervous System1h 6m
- Introduction to the Central Nervous System
  18m
- The Cerebrum
  48m
13. The Peripheral Nervous System1h 26m
14. The Autonomic Nervous System1h 38m
15. The Special Senses2h 41m
16. The Endocrine System2h 48m
17. The Blood3h 22m
18. The Heart3h 42m
19. The Blood Vessels3h 35m
20. The Lymphatic System3h 16m
21. The Immune System14h 37m
22. The Respiratory System3h 20m
23. The Digestive System2h 5m
24. Metabolism and Nutrition4h 0m
25. The Urinary System2h 39m
26. Fluid and Electrolyte Balance, Acid Base Balance37m
27. The Reproductive System2h 5m
28. Human Development1h 21m
29. Heredity3h 32m

28. Human Development

Introduction to Human Development

Anatomy & Physiology

28. Human Development

Introduction to Human Development

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Multiple Choice

Which of the following describes a difference between how monozygotic and dizygotic twins develop?

Monozygotic twins always share the same placenta, whereas dizygotic twins never share a placenta.

Monozygotic twins are always of the same sex, while dizygotic twins are always of different sexes.

Monozygotic twins have different genetic material, whereas dizygotic twins have identical genetic material.

Monozygotic twins develop from a single fertilized egg that splits, while dizygotic twins develop from two separate fertilized eggs.

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Verified step by step guidance

Understand the basic definitions: Monozygotic twins, also known as identical twins, originate from a single fertilized egg that splits into two embryos. Dizygotic twins, or fraternal twins, develop from two separate eggs fertilized by two different sperm cells.

Consider the genetic implications: Monozygotic twins share identical genetic material because they come from the same fertilized egg. In contrast, dizygotic twins have different genetic material, similar to regular siblings, because they come from two separate eggs.

Examine the placental development: Monozygotic twins may share a placenta or have separate placentas depending on when the fertilized egg splits. Dizygotic twins always have separate placentas because they develop from separate eggs.

Analyze the sex of the twins: Monozygotic twins are always of the same sex because they originate from the same fertilized egg with identical genetic material. Dizygotic twins can be of the same or different sexes since they come from two different eggs.

Summarize the key difference: The primary distinction between monozygotic and dizygotic twins is their origin. Monozygotic twins come from a single fertilized egg that splits, while dizygotic twins develop from two separate fertilized eggs.