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