Tissues, Organs and Systems What do they all do? How do they all work together?

Tissues Definition: Groups of similar cells that work together to perform a specific function 4 Major Tissue Types: Epithelial Connective Muscle Nerve

Epithelial Tissue Definition Surface or coverings of organs and body parts, examples include skin, lining of the intestine, etc Purpose: Protection Secretion Absorption Filtration

Protection Skin protects you from external threats Stomach epithelial cells keep the acid inside the stomach to digest the food and not other internal organs!

Secretion Mammary glands secrete milk for nursing infants Salivary Glands allow saliva to be secreted into your mouth so that you can begin digesting food Mammary glands secrete milk for nursing infants

Absorption Food (nutrients) are mostly absorbed in the small intestine by the epithelial cells

Filtration Red Blood Cells Arteries bring oxygen and nutrients to cells and then exchange it for carbon dioxide and other wastes Waste carried to kidneys and liver via the veins

Connective Tissue Definition Supports, binds and connects tissues to one another. Can be physical or functional 8 D is done here Wed Nov 29th

Physical Connective Tissue 1) Bone: physically supports the body 3) Tendons: connects muscle and bone 2) Ligaments: connects bone to bone to form a joint

Functional Connective Tissue Fat is a functional support because it stores fat to be used as energy as required Blood tissue is also functional because it supplies the body with….. OXYGEN

Muscle Tissue Definition Cells designed to contract and therefore allow movement

3 Main Types of Muscle cells Skeletal Smooth Cardiac

Skeletal Muscle Tissue Muscle attached to bone, For example, calf muscle, biceps, etc Muscles contract VOLUNTARILY (with nerve stimulation)

Smooth Muscle Muscle found within our internal organs such as the intestine, bladder and blood vessels Muscles contract INVOLUNTARILY (without nerve stimulation)

Cardiac Muscle Used to pump blood, therefore this muscle is INVOLUNTARY too

Nervous Tissue Definition Groups of nerve cells that send electrical impulses (signals) to the brain

The NEURON

How neurons work Neurons send signals for sensing and reacting to our environment (touch – hot or cold, pressure receptors, etc) They transmit messages to and from the brain

ORGANS DEFINITION 2 or more tissues working together to perform a specific function

ORGAN SYSTEMS DEFINITION 2 or more ORGANS working together to perform a specific function Examples include Circulatory System Respiratory System Digestive system Nervous system Reproductive system Skeletal system

Digestive System Breaks down and absorbs food and nutrients and then helps get rid of the waste

Respiratory System The main function is the exchange of gases: Oxygen IN Carbon Dioxide OUT

Nervous System The main function to relay messages throughout your body

PHEW: That was a lot of information all at once… PHEW: That was a lot of information all at once…..let’s see how much you remember! Take the quiz on the following page by answering the multiple choice questions and filling in the summary blanks