Overview of Human Biology

Overview of Human Biology

• Human biology is the study of the human body, its functions, and its relationship to the environment.
• It encompasses various fields including anatomy, physiology, genetics, and biochemistry.

Major Systems of the Body

1. Skeletal System

   • Composed of bones, cartilage, and ligaments.
   • Functions: supports the body, protects organs, enables movement, stores minerals, produces blood cells.

2. Muscular System

   • Composed of skeletal, smooth, and cardiac muscles.
   • Functions: facilitates movement, maintains posture, generates heat.

3. Nervous System

   • Includes the brain, spinal cord, and nerves.
   • Functions: controls body activities through electrical signals, processes sensory information, coordinates responses.

4. Circulatory System

   • Composed of the heart, blood vessels, and blood.
   • Functions: transports oxygen, nutrients, hormones, and waste products.

5. Respiratory System

   • Comprises the lungs, trachea, and airway passages.
   • Functions: facilitates gas exchange (oxygen and carbon dioxide).

6. Digestive System

   • Includes mouth, esophagus, stomach, intestines, liver, and pancreas.
   • Functions: breaks down food, absorbs nutrients, eliminates waste.

7. Endocrine System

   • Composed of glands such as the thyroid, adrenal, and pancreas.
   • Functions: regulates metabolism, growth, and development via hormones.

8. Immune System

   • Network of cells and tissues including lymph nodes and spleen.
   • Functions: defends against pathogens, removes foreign substances.

9. Reproductive System

   • Involves male (testes, penis) and female (ovaries, uterus) structures.
   • Functions: produces gametes, facilitates reproduction, supports fetal development.

Cellular Biology

• The basic unit of life is the cell, which contains organelles such as:
  • Nucleus: houses genetic material (DNA).
  • Mitochondria: produces energy (ATP).
  • Ribosomes: synthesizes proteins.
• Cell types:
  • Prokaryotic (bacteria) vs. Eukaryotic (animal, plant) cells.

Genetics

• Genes: units of heredity made of DNA that code for proteins.
• Chromosomes: structures that organize DNA within cells.
• Inheritance patterns:
  • Dominant and recessive traits.
  • Mendelian and non-Mendelian inheritance.

Homeostasis

• The body's ability to maintain a stable internal environment.
• Involves feedback mechanisms (positive and negative) to regulate physiological processes.

Development and Aging

• Stages of human development:
  1. Prenatal (fertilization to birth)
  2. Infancy (birth to 2 years)
  3. Childhood (2 to 12 years)
  4. Adolescence (12 to 18 years)
  5. Adulthood (18 years and older)
• Aging: a complex process involving genetic, environmental, and lifestyle factors affecting homeostasis and body systems.

Key Concepts

• Interconnectedness of body systems: all systems work together to maintain health.
• Importance of nutrition, exercise, and lifestyle choices on overall biology and health.
• Ongoing research in human biology influences medical advancements and public health policies.

Human Biology Overview

• The study of the human body, its functions, and its interactions with the environment.
• Encompasses fields such as anatomy, physiology, genetics, and biochemistry.

Major Body Systems

• Skeletal System: Provides support, protects organs, enables movement, stores minerals, and produces blood cells.
• Muscular System: Facilitates movement, maintains posture, and generates heat.
• Nervous System: Controls body activities through electrical signals, processes sensory information, and coordinates responses, consisting of the brain, spinal cord, and nerves.
• Circulatory System: Transports oxygen, nutrients, hormones, and waste products, consisting of the heart, blood vessels, and blood.
• Respiratory System: Facilitates gas exchange (oxygen and carbon dioxide), consisting of the lungs, trachea, and airway passages.
• Digestive System: Breaks down food, absorbs nutrients, and eliminates waste, consisting of the mouth, esophagus, stomach, intestines, liver, and pancreas.
• Endocrine System: Regulates metabolism, growth, and development via hormones, consisting of glands such as the thyroid, adrenal, and pancreas.
• Immune System: Defends against pathogens and removes foreign substances, consisting of cells and tissues like lymph nodes and the spleen.
• Reproductive System: Produces gametes, facilitates reproduction, and supports fetal development, consisting of male (testes, penis) and female (ovaries, uterus) structures.

Cellular Biology

• The basic unit of life is the cell, containing organelles such as:
  • Nucleus: Houses genetic material (DNA).
  • Mitochondria: Produces energy (ATP).
  • Ribosomes: Synthesizes proteins.
• Cell Types:
  • **Prokaryotic cells **(bacteria) are simple cells without a nucleus or other membrane-bound organelles.
  • Eukaryotic cells (animal, plant) are more complex cells with a nucleus and other membrane-bound organelles.

Genetics

• Genes: Units of heredity made of DNA that code for proteins.
• Chromosomes: Structures that organize DNA within cells.
• Inheritance Patterns:
  • Dominant and recessive traits: Determine how traits are passed from parents to offspring.
  • Mendelian and non-Mendelian inheritance: Describe the different ways traits are inherited.

Homeostasis

• The body's ability to maintain a stable internal environment despite external changes.
• Involves feedback mechanisms (positive and negative) to regulate physiological processes.

Development and Aging

• Stages of Human Development:
  • Prenatal (fertilization to birth)
  • Infancy (birth to 2 years)
  • Childhood (2 to 12 years)
  • Adolescence (12 to 18 years)
  • Adulthood (18 years and older)
• Aging: A complex process influenced by genetic, environmental, and lifestyle factors impacting homeostasis and body systems.

Key Concepts

• Interconnectedness of body systems: All body systems work together to maintain health.
• Importance of nutrition, exercise, and lifestyle choices: Directly impact overall biology and health.
• Ongoing research in human biology: Influences medical advancements and public health policies.