
What are the levels of organization in the body?

What are the major body systems?

What types of tissue make up the human body?

Discover Activity: How Does
Your Body Respond?
1. Stack one book on top of another one.
2. Lift the two stacked books in front of you so the lowest book is about level with your shoulders.
3. Hold the books in this position for 30 seconds.
4. While you are performing this activity, note how your body responds.
Afterwards: List all of the parts of your body that worked together during this activity

Levels of Organization

Try this:

1. Examine how a test book is subdivided-into chapters, sections, etc.

2. make a concept map that shows this pattern of organization.

Compare the organization of the text book with the organization of the human body.
Science
Text Book
Unit 1
Unit 2
Chapter 1
Chapter 2
Chapter 3
Chapter 4
Section 1
Section 2
Section 3

Levels of Organization
Organism
Organ
System
Organ Tissue Cells

Human
Body
Circulatory
Digestive
Nervous
Skeletal
Respiratory
Muscular
Endocrine
Brain
Spinal
Cord
Nervous
Tissue
Nerve Cells

Cells

A cell is the basic unit of structure and function in a living thing

Cell membrane

Nucleus

Cytoplasm

Function of Cells

Release energy for the body’s functions

Grow and reproduce

Get rid of waste products

Tissues

A tissue is a group of similar cells that perform the same function

Types of Tissues:

Muscle

Nervous

Connective

Epithelial

Organs and Organ Systems

An organ is a group composed of different tissues that perform a specific function

An organ system is a group of organs that work together to perform a major function

1.
Skeletal
2.
Muscular
3.
Skin
(Integumentary)
4.
Digestive
5.
Circulatory
6.
Respiratory
7.
Exretory
8.
Nervous
9.
Endocrine
10.
Reproductive
11.
Blood
(Lymphatic)

Essential Questions

What is homeostasis?

How do your body systems work together to help maintain homeostasis?

What are the functions of the skeleton?

Homeostasis

Homeostasis is the process by which an organism’s internal environment is kept stable in spite of changes in the external environment.

Maintain homeostasis

Stress is the reaction of your body to potentially harmful, challenging, threatening or disturbing events.

Functions of the Skeletal
System

Shape and support

Protects organs

Allows for movement

Produces blood cells

Stores minerals and other materials

Joints

A joint is a place in the body where two different bones come together

Immovable jointsAllow for little to no movement

Moveable joints - Allow for movement; held together by ligaments and cartilage.

Types of Joints

Hinge

Ball and Socket

Pivot

Gliding

Bone Structure


Compact bonehard and dense but not solid

Spongy bonehas many small spaces within it, allows bones to be lightweight

Bone marrowsoft connective tissue inside of bone

Red marrow produces most of the body’s blood cells

Yellow marrow stores fat and serves as an energy reserve


What types of muscles are found in the body?

Why do skeletal muscles work in pairs?


Muscles can voluntary or involuntary

The 3 types of muscles in the body are :

Cardiac

Smooth

Skeletal

Skeletal Muscle

Attached to the bones of your skeleton

Provide the force that moves your bones

Has a banded, or striated appearance

A tendon can be found at the end of each skeletal muscle

Tendonstong connective tissue that attaches muscle to bone

Smooth Muscle

Involuntary

Found inside many internal organs

Work automatically to perform certain functions inside the body

React and tire more easily than skeletal muscles

Cardiac Muscle

Found only in the heart

Striated

Involuntary

Does not get tiered

Muscles Work In Pairs

Because muscle cells can only contract, not extend, skeletal muscles must work in pairs

While one muscle contracts, the other relaxes to its original length

Example: biceps and triceps

Essential Questions

What are the functions of the nervous system?

What is the structure of a neuron and what kinds of neurons are found in the body?

How do nerve impulses travel from one neuron to another?


Receiving information

Responding to information

Stimulus - a change or signal that can make an organism react

Response - what your body does to react to the stimulus

Maintaining homeostasis

The Neuron

Neuron - nerve cell

Nerve impulse - the message a neuron carries

Structure:

Large cell body

Dendrites

Axon

Dendrites carry impulses towards the neuron’s body cell

The axon carries nerve impulses away from the cell body

Types of Nerves

Sensory Neurons- pick up stimuli from the internal or external environment and converts each stimulus into a nerve impulse

Interneuron- carries nerve impulses from one neuron to another

Motor Neuron- sends an impulse to a muscle or gland, causing a resonse

The Central Nervous System

Consists of the brain and spinal cord

Control center of the body

Controls all information about what is happening in the world around in as well as inside of your body

The Peripheral Nervous
System

Consists of all the nerves located outside of the central nervous system

Network of nerves that branch out from the central nervous system

Involved in voluntary and involuntary actions

Composed of 43 pairs of nerves

The Cerebrum
The portion shown in blue is the cerebrum

Cerebrum

Largest part

Interprets input from the senses

Controls movement and carries out complex mental processes

Divided into a R and L side

The right side sends impulses to skeletal muscles on the left side, while the left side controls the right side

The right side is associated with creativity and artistic ability

The left is associated with logical and mathematical thinking

The Cerebellum

Second largest part

Coordinates the actions of your muscles and helps you keep balance

Brain Stem

Lies between the cerebellum and spinal cord

Controls the body’s involuntary actions

Spinal Cord

The link between your brain and the peripheral nervous system

Connected to the midbrain and the medulla

Peripheral Nervous System
(PNS)

43 pairs of nerves plus 31 pairs of spinal nerves

Spinal nerves are like a two way highway, carrying impulses to and from the central nervous system

The nerves of the peripheral nervous system are separated into the somatic and autonomic systems

Somatic nervous system controls voluntary actions

Autonomic nervous system controls involuntary actions

Your Digestive System


Digestion
 process by which your body breaks down food into small nutrient molecules is called

Absorption
 the process by which nutrient molecules pass through the wall of your digestive system into your blood.

Elimination

Organs of the Digestive
System

The Mouth

The Esophagus

The Stomach

The Small and Large Intestine

Your Body’s Transport System

Components

The Heart

Blood Vessels

Blood

Functions

Delivering needed materials

Removing Waste Products

Fighting Disease

The Heart

The heart is a hollow, muscular organ that pumps blood through the body

Has a R and L side

R and L side separated by the septum

Each side has two chambers- an upper and a lower

Upper chambers = atrium

Lower Chambers = ventricle

Pathway of Blood

Components

Nose

Pharynx

Trachea

Bronchus

Lungs

Functions

Moves oxygen from the outside environment into the body

Oxygen is needed for cellular respiration

The process in which oxygen and glucose undergo a complex series of reactions in the cell

Removes CO
2 and H
2
O from the body

Tying It all Together

Functions

Collects waste produces by cells

Removes waste from the body

Components

Kidneys

Ureter

Urinary Bladder

Urethra

Functions

Produces chemicals that control many of the body’s daily activities

Regulates long-term changes such as growth and development.

Components

Glands

A gland is an organ that releases hormones

Endocrine glandsproduce and release chemicals directly into the bloodstream

Hormones

HormonesChemicals released by glands that speed up, slow down, turn on or turn off organs in the body

When hormones enter the bloodstream they affect only target cells, which are cells that recognize specific hormones

Endocrine Glands

Hypothalamus

Pituitary

Thyroid

Parathyroid

Adrenal

Thymus

Pancreas

They also include the ovaries in females and testes in males

Hypothalamus and Pituitary
Glands