8th grade-ch.1 sec. 1 body organization & homeostasis

Ch. 1Ch. 1Sec. 1 Body Sec. 1 Body

Organization & Organization & HomeostasisHomeostasis

levels of organizationin body

cells tissues organs

organ systems

Cell Size and Scale

Cell TypesCell Types

Bone Cell

Muscle Cell

Nerve Cell

Cartilage Cell

Blood Cell

Small IntestineCell

CELL CELL STRUCTURESSTRUCTURES

(organelles)(organelles)

cell cell membranemembrane nucleusnucleus cytoplasmcytoplasm

Cell MembraneCell Membrane

forms outside boundary of cell

NucleusNucleus control center- directs cell’s

activities

The nuclei can be seen in the photograph of human cheek cells below.

CytoplasmCytoplasm clear, jellylike substance contains organelles

4 basic types

of tissues

muscle tissue

nervetissue

connectivetissue

epithelial tissue

4 basic types

of tissues

muscle tissue

nervetissue

connectivetissue

epithelial tissue

movementContracts& shortens

4 basic types

of tissues

muscle tissue

nervetissue

connectivetissue

epithelial tissue

MovementContracts &

shortens

Directs & controls movement

Carries messages back & forth from brain

4 basic types

of tissues

muscle tissue

nervetissue

connectivetissue

epithelial tissue

MovementContracts &

shortens

Directs & controls movement

Carries messages back & forth from brain

Connects & supports

4 basic types

of tissues

muscle tissue

nervetissue

connectivetissue

epithelial tissue

movementContracts& shortens

Directs & controls movement

Carries messages back & forth from brain

Connects & supports

Covers body surfaces in & out

Absorbs & releases chemicals

Bone & fat

Tissues

An organ is a structure that is made of different kinds

of tissue. Your stomach, heart, brain, and lungs are all organs.

Each organ in your Each organ in your body is part of an body is part of an

organ system.organ system. Your heart is part of your circulatory system, which carries oxygen and other materials throughout the body.

Besides the heart, blood vessels are organs in the circulatory system.

organ systems

Circulatory SystemFUNCTIONSFUNCTIONS

carries needed materials to body cells

carries wastes away from body

helps fight disease

homeostasis process by which an organism’s internal

environment is kept stable in spite of changes in external environment

examples:

1. internal body temp.= 37 degrees Celsius no matter outside temp.

2. perspiring on a hot day

Maintaining Homeostasis Regardless of the surrounding temperature, your body temperature remains fairly constant at about 37°C. Sweating and shivering help regulate your body temperature.

stress reaction of your body & mind

to threatening, challenging or disturbing events

disrupts homeostasis

Cell MembraneCell Membrane surrounds cytoplasm allows water, oxygen & other

materials to pass in & out of cells

NucleusNucleus cell’s command center contains cell's DNA (genetic code)

CytoplasmCytoplasm material between nucleus & cell

membrane contains organelles & nutrients

List the 4 levels of organization in the human body. Give an example of each level.

cell- bone cell tissue- muscle tissue organ- heart organ system- circulatory system

What are the 4 types of tissue found in the human body? What is the general function of each type?

muscle tissue= movement nerve tissue= carries messages

between the brain and other parts of the body

connective tissue= provides support and connects all parts of the body

epithelial tissue= covers surfaces of body; absorbs & releases substances

Describe the structure of an animal cell.

The cell membrane forms the outside boundary of the cell.

Inside the cell membrane is the nucleus, the control center of the cell.

The area between the nucleus and cell membrane is the cytoplasm, which contains important cell structures.

What systems of the body are involved when you prepare a

sandwich and then eat it?skeletal systemnervous systemmuscular systemcirculatory systemdigestive system

What is homeostasis ? process by which an organism’s internal

environment is kept stable in spite of changes in external environment

examples:

1. internal body temp = 37 degrees Celsius no matter outside temp.

2. perspiring on a hot day

What is stress? How does it affect homeostasis? reaction of your body & mind

to threatening, challenging or disturbing events

upsets homeostasis