Pg:- 20
1. Circulatory System
Components: Heart, blood vessels (arteries, veins, capillaries), blood. Functions:
Transports oxygen, nutrients, hormones, and waste products throughout the body.
Maintains body temperature and pH balance.
Protects the body with clotting mechanisms and immune responses.
2. Respiratory System
Components: Lungs, trachea, bronchi, diaphragm, nasal passages. Functions:
Facilitates gas exchange (oxygen and carbon dioxide) between the air and the blood.
Maintains the body's pH balance by regulating the concentration of carbon dioxide in the blood.
3. Digestive System
Components: Mouth, esophagus, stomach, small intestine, large intestine, liver, pancreas, gallbladder. Functions:
Breaks down food into nutrients that the body can absorb.
Eliminates solid waste products.
Regulates water balance and electrolyte levels.
4. Nervous System
Components: Brain, spinal cord, peripheral nerves, sensory organs. Functions:
Controls and coordinates body activities by transmitting electrical impulses.
Processes sensory information and governs responses.
Responsible for cognition, memory, and learning.
5. Endocrine System
Components: Glands (pituitary, thyroid, adrenal, etc.), hormones. Functions:
Regulates bodily functions through the secretion of hormones.
Controls growth, metabolism, reproductive processes, and stress responses.
6. Musculoskeletal System
Components: Bones, muscles, cartilage, tendons, ligaments, joints. Functions:
Provides structure and support to the body.
Facilitates movement through muscle contraction and joint articulation.
Protects vital organs.
7. Integumentary System
Components: Skin, hair, nails, sweat glands, sebaceous glands. Functions:
Protects the body from external harm (e.g., pathogens, chemicals).
Regulates body temperature.
Provides sensory information and synthesizes vitamin D.
8. Lymphatic/Immune System
Components: Lymph nodes, lymphatic vessels, spleen, thymus, bone marrow, white blood cells. Functions:
Defends against infections and diseases.
Maintains fluid balance by returning interstitial fluid to the bloodstream.
Absorbs and transports fats from the digestive system.
9. Urinary System
Components: Kidneys, ureters, bladder, urethra. Functions:
Removes waste products and excess substances from the blood.
Regulates blood volume and pressure.
Maintains electrolyte and acid-base balance.
10. Reproductive System
Components (male): Testes, penis, vas deferens, seminal vesicles, prostate gland. Components (female): Ovaries, fallopian tubes, uterus, vagina, mammary glands. Functions:
Produces gametes (sperm in males, eggs in females).
Facilitates fertilization and supports fetal development in females.
Produces sex hormones that influence secondary sexual characteristics and reproductive functions.
Integration of Systems
The human body’s systems are highly interdependent. For example:
The circulatory and respiratory systems work together to deliver oxygen to and remove carbon dioxide from cells.
The nervous and endocrine systems coordinate to regulate body functions, with the nervous system providing rapid responses and the endocrine system providing longer-lasting effects.
The digestive and urinary systems manage the intake, processing, and elimination of nutrients and waste products.
Homeostasis is a fundamental principle of physiology where systems work together to maintain a stable internal environment despite external changes. For instance, the body regulates temperature through the integumentary system (sweating or shivering), and maintains pH balance through the respiratory and urinary systems.