Unit #1: Wellness And HomeostasisCells and Homeostasis (1)

“Histology and Organization”

Generally speaking, animal and plant bodies are organized in the following manner

Cells Tissue Organ Organ System

Cells • The basic structural, functional and

biological unit of a living organism

2 types:

Prokaryotic Cells:

– Basic cells found in bacteria

– Smaller, lack organelles, lack a true nucleus and

carry minimal amounts of genetic material

Eukaryotic Cells:

– Larger more complex cells found in fungi, animal

and plant life.

– Contain organelles

– Have specialized functions

– Have a true nucleus which contains more condensed

genetic material

Organelle – a membrane bound structure within a cell that

performs some type of cellular function

Tissue • A group of similar cells that work together to

perform a specific function

4 general types of Animal Tissue:

“Connective Tissue”

– Fibrous tissue made up of cells separated by non – living

material called an “extracellular matric”

– Matrix can be liquid or solid

– This type of tissue gives shape to organs and can hold

them in place

– Blood, Bone, Tendons, Ligaments, Fat and Lung tissues

are examples of Connective Tissue

“Muscle Tissue”

– Tissues made up of muscle cells that are used to cause

movement (body movement, organ movement, movement

of material within the body)

– Tissue is made up of long narrow cells

“Nervous Tissue”

– Neural tissue made up of specialized cells called

neurons

– Used to carry impulses to and from the body’s central

nervous system

“Epithelial Tissue”

– Tissue formed by cells that cover the surfaces (internal

and external) of organs.

– “linings”

– used to protect organ surfaces

– Helps with absorption of water and nutrients

– Helps with the elimination of waste

– Can form glands that secrete enzymes and hormones

Organ

Organ System

Histology

• A collection of tissues joined in a structural

unit to serve a common function

• Two or more organs working together to

perform a specific body function

• The study of cells and tissues

• Scientists can gauge the health and function of

an organ or organ system by analyzing the

function of the tissues and cells that the organ

is made up of.

So, what does this have to do with Homeostasis?