1. Organ Systems: Structure & Function

2. Organ Systems
Groups of organs that work together to accomplish a specific life function.
Different ways to count the number of systems in the human body – we’ll look at 11.
Systems actually work with and influence each other – they’re not completely independent.

3. Cardiovasculaar System
Reproductive System
Integumentary System
Skeletal System
Nervous System
Urinary System
Cardiovasculaar System
Muscular System
Digestive System
Respiratory System
Lymphatic System

4. Integumentary System Forms the external body covering
Composed of the skin, sweat glands, oil glands, hair, and nails
Protects deep tissues from injury, regulates body temperature, synthesizes vitamin D, provides sense of touch
Figure 1.3a

5. Skeletal System Composed of bone, cartilage, and ligaments
Protects and supports body organs
Provides the framework for muscles
Site of blood cell formation
Stores & releases minerals including Ca++
Figure 1.3b

6. Muscular System Composed of muscles and tendons
Movement! Allows manipulation of the environment, locomotion, and facial expression
Maintains posture
Produces heat
Figure 1.3c

7. Nervous System
Composed of the brain, spinal cord, nerves, and sense organs
Is the fast-acting control system of the body
Responds to stimuli by activating muscles and glands
Includes 3 types of neurons:
Sensory neurons gather information
Interneurons analyze information and make decisions
Motor neurons send commands to muscles and glands
Figure 1.3d

8. Cardiovascular System aka, Circulatory System
Composed of the heart and blood vessels
The heart pumps blood
The blood vessels transport blood throughout the body
Arteries carry blood away from the heart
Veins carry blood to the heart
Capillaries exchange gases, nutrients, and wastes with body cells
Figure 1.3f

9. Lymphatic System, aka Immune System
Composed of red bone marrow, thymus, spleen, lymph nodes, and lymphatic vessels
Picks up fluid leaked from blood vessels and returns it to blood
Disposes of debris in the lymphatic stream
Houses white blood cells involved with immunity
Figure 1.3g

10. Respiratory System
Composed of the nasal cavity, pharynx, trachea, bronchi, and lungs
Keeps blood supplied with oxygen and removes carbon dioxide
“Gas exchange:” trades O2 for CO2
Figure 1.3h

11. Digestive System
Composed of the oral cavity, esophagus, stomach, small intestine, large intestine, rectum, anus, gall bladder, and liver
Breaks down food into absorbable units that enter the blood
Eliminates indigestible foodstuffs as feces
Figure 1.3i

12. Urinary System, aka Excretory System
Composed of kidneys, ureters, urinary bladder, and urethra
Eliminates nitrogenous wastes from the body
Regulates water, electrolyte, and pH balance of the blood
Figure 1.3j

13. Male Reproductive System
Composed of prostate gland, penis, testes, scrotum, and ductus deferens (vas deferens)
Main function is the production of offspring
Testes produce sperm and male sex hormones
Ducts and glands deliver sperm to the female reproductive tract
Figure 1.3k

14. Female Reproductive System
Composed of mammary glands, ovaries, uterine tubes, uterus, and vagina
Main function is the production of offspring
Ovaries produce eggs and female sex hormones
Remaining structures serve as sites for fertilization and development of the fetus
Mammary glands produce milk to nourish the newborn
Figure 1.3l

15. Endocrine System Includes various glands throughout the body
Examples: Pituitary gland, pineal gland, thymus, pancreas, thyroid gland, adrenal glands, ovaries, testes.
Releases hormones that regulate metabolism, growth, development, tissue function, and influence mood.

16. A Couple of Mnemonics for You!
For fans of Arthurian legends:
Dr. Merlin, S.E.C.
Or, if you’re interested in Forensics:
(Sorcerer of Extreme Competency)
Crime Sein Dr.
(OK, so it’s misspelled – but if it helps you remember, use it!)

17. An Example of Organ System Interrelationships
The integumentary system protects the body from the external environment
Digestive and respiratory systems, in contact with the external environment, take in nutrients and oxygen
Nutrients and oxygen are distributed by the blood
Metabolic wastes are eliminated by the urinary and respiratory systems

18. Figure 1.2