The Human Body:An Orientation

Part 1

Review What is Anatomy?

Give an example of Anatomy of the Cardiovascular System

What is Physiology? Give an example of Physiology of the Digestive

System

Overview Levels of Structural Organization Maintaining Life Homeostasis

Levels of Structural Organization What is the smallest thing known to

Humankind? What are ALL THINGS (living and non-living)

made of?

From Atoms to Organisms 1) Atoms

Tiny building blocks of matter

2) Cells The smallest unit of living things

3) Tissues A group of similar cells that have a common

function

From Atoms to Organisms 4) Organ

Made of two or more tissues and performs a specific function for the body

5) Organ System A group of organs that cooperate to accomplish

a common purpose 6) Organism

A group of organ systems that make up the highest level of living structural organization

The Human Organism Can you name all 11 organ systems that

make up the human organism?

Body Systems Skeletal System Muscular System Nervous System Endocrine System Cardiovascular System Lymphatic System Respiratory System Digestive System Urinary System Reproductive System

Maintaining Life 1) Maintaining Boundaries

Organisms must keep their “insides” separate from the “outside”

Which Human Body System maintains this essential boundary?

Why is maintaining a boundary important?

Maintaining Life 2) Movement

Necessary for motility and to perform bodily functions such as digestion and pumping blood.

Which Human Body System is responsible for movement?

Why is motility important?

Maintaining Life 3) Responsiveness

The ability to sense changes in the environment and react to them

What TWO Human Body Systems are responsible for responsiveness?

Why is responsiveness important?

Maintaining Life 4) Digestion

The process of breaking down food into molecules that can be used by the body

5) Metabolism All chemical reactions that occur in the body

6) Excretion The process of removing wastes from the body

Maintaining Life Why is it important to be able to break

down food through digestion? Why do you think chemical reactions are

necessary in the body? Why is it important to be able to excrete

waste from the body?

Maintaining Life 7) Reproduction

The production of offspring

Why is reproduction an important function of the body?

Maintaining Life 8) Growth

An increase in size

Why is growth an important aspect of living things?

Maintaining Life Survival Needs

Nutrients Oxygen Water Body Temperature Atmospheric Pressure

Homeostasis What do you think Homeostasis means?

Homeostasis Homeostasis

The body’s ability to maintain relatively stable internal conditions despite ever-changing external conditions

In your notes, write a definition with an example in your own words.

Homeostasis How do we control Homeostasis?

Negative Feedback Loops (Feedback Inhibition) A system in which the effect of a stimulus turns off

or reduces the original stimulus

Lets look at an example

Feedback Inhibition Loop:A home heater

Room Temp. Decreases

Room Temp. Increases

Thermostat senses temp. increase and switches heater off

Thermostat senses temperature decrease and switches heater on

How is the house heater like the Human Body?

What happens to you when you get very cold?

Feedback Inhibition Loop:Your Body - too COLD

BODY Temp. Decreases too much

BODY Temp. Increases to normal

Your body stops shivering (Thermostat OFF)

Your body shivers and shakes to warm you (thermostat ON)

What about when you get too hot? What happens?

Feedback Inhibition Loop:Your Body - too HOT

BODY Temp. Decreases to normal

BODY Temp. Increases too much

Your body produces sweat to cool you.

Your body stops producing sweat

Feedback Inhibition

Feedback inhibition is a process utilized by many body systems in order to maintain homeostasis.

Homeostasis Write in your notes an example that will

help you remember what Negative Feedback is.

What happens when our bodies are unable to maintain homeostasis? (Homeostatic Imbalance)

Quick Quiz Name the 6 levels of living structural

organization. Name one of the requirements for

maintaining life, and say why it is important. Give a definition for Homeostasis IN YOUR

OWN WORDS Give an example of a Negative Feedback

Loop