Is It Alive?

How do we know when something is alive?

The world is made up of many different things.

– Some things, like plants and animals, are living.

– Other things, like cars and rocks are non-living.

Living things are called *organisms*

Living or Non-living?

You know plants and animals are living things. How do you know this? All living things (YES, ALL LIVING THINGS)

have certain characteristics in common. We will remember them by remembering THIS

phrase: STRANGER-C

S T R A N G E R C There are 9 characteristics (processes) which are necessary

for life:

Synthesis Transport Respiration Adaptation/Response Nutrition Growth/Genetics Excretion Reproduction Cells

Synthesis

Synthesis means to make / build something more complex Think Legos

Transport

Transport means movement Transportation is the process

by which substances enter and leave our cells and become distributed within the cells Think of water moving from the

roots of a tree all the way to the leaves at the top of the branches

Think of your blood circulating through your body

Respiration

Cell Respiration the process of changing energy stored in food into a chemical energy (ATP) which cells can use

Two types: Aerobic – Uses oxygen Anaerobic – Does not use oxygen

AKA: FERMENTATION

Adapt/Respond Adaptation is any inherited factor that improves the

chances of survival All living things need to adapt and respond to their

environment if they are to survive Adapting means changing to be better able to survive

Think of polar bears in sub-zero temperature Responding means reacting to changes in the

environment Stimulus = any factor (signal) that causes a change/response

- It’s a change in the environment which causes a reaction Doorbell Phone Ringing

Response = a reaction to a change caused by a stimulus Goosebumps Sweat

Kn

ow

th

ese

2!

Nutrition Nutrition means taking in

nutrients needed to make energy and survive Ingestion means to take IN food

Think of you munching on a Big Mac Digestion means breaking down

large “stuff” (complex materials) into smaller/simpler forms That Big Mac doesn't go sloshing

around beneath your skin, smearing ooey-gooey yummy-ness all over your muscles and bones, does it????

Growth & Genetics

Growth means to increase in size and/or number Even though we appear to stop growing… we

always need new cells to repair/replace old ones! Genes are necessary for this to happen!

Your GENES are made up of DNA that contains the instructions for the cell (and we'll learn TONS about that later on!)

Excretion Excretion means to get rid of

cellular waste (NOT POOP!) You excrete in many ways:

Pee-ing (Yup.... I said that too!) Sweat

Ever wonder why the underarm area of your favorite white tee-shirt ends up stained and yellowed????

Breathing What happens when you

breath on a mirror???

Reproduction Reproduction means that living

things are able to make more of their own kind (offspring).

Two types: Asexual – one individual produces

offspring which are identical to the parent

Sexual – two individuals are required to produce offspring and the organism they produce is not identical to either parent

This is the ONLY life-characteristic that is

NOT required for an organism to stay alive....

CELLS

Cells are the building blocks of EVERY living organism The basic unit of structure and

function of all living things EVERY single cell is actually

alive and.... Can exist on it’s own

unicellular Or work with other cells to make

a different organism multicellular

Needs of Living Things

• ALL living things NEED certain things to survive

• Can you think of anything you would NEED in order to stay alive?

• Remember… NEEDING something is different from WANTING something!

• List a few “NEEDED” things:

Needs of Living ThingsALL living things NEED certain things to

survive:

ENERGY – The primary source of energy for ALL life on earth is the SUN

FOOD & WATER – ~70% of your body is water!

AIR – Air is made of the gases which plants and animals need to survive

LIVING SPACE – Living things need a place to get food, water and energy

PROPER TEMPERATURE –The internal temperature must remain in a certain range….

Important Words to Know !!!!!

Metabolism = ALL the chemical reactions occurring within an organism

Homeostasis = “Steady State”. Maintaining a stable internal environment (Even when the external environment changes!)- What’s your body temperature??? Do you think it changes (inside) if it’s super cold

outside??? Super hot???