2.1 CELLS & CELL SYSTEMSHow are they organized?

Cells

Tissues

Organs

Systems

Group of cells that are similar in shape and

function

Groups of different tissues put together for at least one

function

Groups of organs that have related function

CELL ORGANIZATION

Cell and Tissue types

EPITHELIAL TISSUE Covers the outside surfaces of your

body. Covers the inside of your body. Serves as membranes lining organs. Separates organs and keeps them in

place. Skin, inside of mouth, stomach, tissue

surrounding the body’s organs.

CONNECTIVE TISSUE Adds support to the body Adds structure to the body Contains fibrous strands – collagen Skin, tendons,

ligaments, cartilage, bone and fat tissue.

Blood is considered a connective tissue.

MUSCLE TISSUE Muscle is a specialized tissue because

it can contract.

NERVE TISSUE Can generate and conduct electrical

signals. Managed by nerve tissue in brain. Transmitted down spinal cord.

Organs

ORGANS The next level of organization in the body An organ contains at least two different types of

tissue functioning together for a common purpose. Liver, kidneys, heart, lungs, skin Skin – 3 layers 1) epidermis 2) dermis 3)

subcutaneous layer

RESPIRATORY SYSTEM Major Role Provide gas exchange between blood

and environment. Oxygen is absorbed from atmosphere. Carbon dioxide is expelled from body. Major Organs Nose. Trachea Lungs

CIRCULATORY SYSTEM Major Role Transport nutrients, gases (O2, CO2),

hormones, waste Major Organs Heart, blood vessels, blood

EXCRETORY SYSTEM Major Role Filter out wastes, toxins, excess

water, nutrients from circulatory system.

Major Organs Kidneys, urteters, bladder, urethra

DIGESTIVE SYSTEM Major Role Breakdown nutrients Absorb nutrients Major Organs Mouth Esophagus Stomach Small intestine Large intestine

NERVOUS SYSTEM Major Role Relay electrical signals throughout the body Directs behavior and movement Controls digestion, circulation Major Organs Brain Spinal cord Peripheral nerves

ENDOCRINE SYSTEM Major Role Relay chemical messages through the

body Works with nervous system to control

nutrient absorption growth etc. Major Organs Hypothalamus Pituitary Thyroid Pancreas Adrenal glands

Major Role Manufacture cells for reproduction In male – sperm In female - eggs Major Organs Male – testes, seminal vesicles and

penis Female – ovaries, oviducts, uterus,

vagina and mammary glands.

REPRODUCTIVE SYSTEM

MUSCULAR SYSTEM Major Role Provide movement Work in pairs Provide movement in organs,

stomach, intestine, heart, circulatory system.

Major Organs Skeletal muscles throughout body Smooth muscles throughout body

LYMPHATIC / IMMUNE SYSTEM Major Role Destroy and remove invading

microbes and viruses. Remove fat and excess fluids from

blood. Major Organs Lymph Lymph nodes and vessels White blood cells T cells B cells

SKELETAL SYSTEM Major Role Provide support for the body Protect delicate internal organs Provide attachment sites for organs Major Organs Bones Cartilage Tendons Ligaments

QUESTIONS Define; tissue, organ, organ system. Give an example of each. Organize the following structures from smallest to largest and

give an example: tissue, cell, organ, molecule Make a table to compare the levels of cell organization (pg 42)

with the levels in some organization that you are familiar with such as: sports team RPG The school system Government system Banking system Family tree of authority Police structure of authority

Science Probe 8 - pg 42