1. Human Body Systems
Chapter 35-1

2. Organization of the body
1. CELLS:
Simplest, lowest level of organization
Each cell type has a different function and special features
All cells have the same DNA within one organism
2. TISSUE:
A group of cells that work together with a common function
4 types:
Epithelial – lines surfaces of organs
Connective – support for the body and connect different parts
Nervous – transmits nerve impulses through body
Muscle – moves body parts and organs

3. Picture of Body Tissues
4 basic tissues from non-related
locations
4 basic tissues in related locations of one organ

4. Organization of the body Continued
3. Organs:
A group of different tissues that work together with a common function
Ex: Eye, heart
4. Organ Systems:
A group of organs that work together with a common function
There are 11 organ systems

5. Maintaining Homeostasis: Feedback Inhibition
In order to maintain homeostasis (a stable internal environment), the human body is constantly monitoring itself
In order to keep body levels in a constant range, a process called “Feedback Inhibition” is used
When the concentration or amount of something gets too high, it causes the production to shut off
When the concentration or amount of something gets too low, it causes the production to turn on
Example: Home heating system
If you set the thermostat to 70, the heater warms the house until that temperature
An internal sensor shuts off the heater when the temperature is 70
If the temperature drops too far below 70, the internal sensor turns the heater back on

6. How is Feedback Inhibition Used in the Body?
Maintaining homeostasis requires all 11 body systems to work together
Feedback Inhibition is used to maintain normal levels of the following:
Temperature (Similar to a home heating system)
Nervous, integumentary, and muscular systems all work together pH
Water concentration
Hormone Levels
Many more!!

7. Body Systems: Integumentary
Includes:
Skin, hair, nails, sweat and oil glands
Function:
Regulated body temp
Excrete a small amount of waste through sweat
Protective barrier from invaders and infection
Protection from UV radiation

8. Body Systems: Skeletal
Includes:
Bones, cartilage, ligaments, tendons
Functions:
Supports the body
Protects internal organs
Allows movement (in conjunction with the muscular system)
Stores minerals (ex: Calcium)
Site of blood cell formation

9. Body Systems: Muscular
Includes:
Skeletal muscle
Smooth muscle
Cardiac muscle
Functions:
Works with the skeletal system to produce voluntary movement
Helps circulate the blood
Moves internal organs

10. Body Systems: Excretory
Includes:
Skin
Lungs
Kidneys
Ureters
Urinary bladder
Urethra
Function:
Eliminates cellular, metabolic waste

11. Body Systems: Digestive
Includes:
Mouth, pharynx, esophagus, stomach, small and large intestines, rectum
Function:
Converts foods into simpler molecules tat can be used by the cells of the body: absorbs food, eliminates non-digestable material

12. Body Systems: Circulatory
Includes:
Heart
Blood vessels
Blood
Function:
Brings oxygen, nutrients, and hormones to cells
Fights infection
Removes cell wastes
Helps to regulate body temperature

13. Body System: Respiratory
Includes:
Nose
Pharynx
Larynx
Trachea
Bronchi
Bronchioles
Alveoli
Function:
Provides oxygen needed for cell respiration and removes excess carbon dioxide
Aka: Gas exchange

14. Body Systems: Nervous Includes: Brain, spinal cord, peripheral nerves
Functions:
Recognizes and coordinates responses to changes in the internal and external environment
Maintains short-term homeostasis

15. Body Systems: Endocrine
Includes:
Hypothalamus, pituitary, thyroid, parathyroids, adrenals, pancreas, ovaries (in females), testes (in males)
Function:
Controls growth and development
Controls metabolism
Maintains homeostasis over the long-term

16. Body Systems: Reproductive
Includes:
Testes, epididymis, vas deferens, urethra and penis (males)
Ovaries, Fallopian tubes, uterus, vagina (females)
Function:
Produce reproductive cells
In females: protect, nurture and develop an embryo

17. Body Systems: Lymphatic/Immune
Includes:
White blood cells, thymus, spleen, lymph nodes, lymph vessels
Function:
Helps protect the body from disease
Collects fluid lost from blood vessels and returns the fluid to the circulatory system