Science Starter #1

What characteristics do living
organisms have in common?
Chapter 1 Sections 1-1
Pages 4-9
Biology

Biology – the study of life
What is life?
Characteristics of Life
#1 Cells

 Cells: the smallest unit that can perform life
processes
 Basic building blocks of organisms.
 All living things are either:
 Unicellular – single celled organisms
 Multicellular – organisms composed of multiple cells
#2 Organization
Organization – organisms show high degree
of both internal and external organization

 Highly organized at the cellular and/or
molecular level.
 Specific cell structures carry out specific functions
 In multicellular organisms, cell types group
together based on function (specialization)
 Ex. The ear is made of many cells that are
specialized and organized specifically to hear
sound.
#3 Homeostasis

Homeostasis: organisms maintain a
stable internal environment
Ex. body temperature, water content
Humans maintain body temp. at 98.7˚F,
our kidneys help regulate the amount of
water in our bodies
#4 Metabolism

Metabolism – all of the chemical
processes in the body
 Organisms require and use energy
to maintain their organization.
Two Types of Metabolism
 Autotrophs- produce own
nutrients and energy
 i.e. photosynthesis
 Heterotrophs- get nutrients and
energy from eating other
organisms
#5 Response to
Environment

Response to the environment
Stimulus – a physical or chemical change
in the environment
Response – an organisms reaction to a
stimulus
Ex. when a cat feels threatened they puff up
and arch their back
 What could be the stimulus here?
 What was the response?
#6 Growth

Growth - Materials are
converted by the organism
to make more cells.
Cell division produces two
new cells.
Development: organisms
become a mature adult as
cells divide and specialize.
# 7 Reproduction

 Reproduction - Organisms can create new organisms
similar to themselves
 Heredity, the ability to pass traits on through genes
#8 Change Through
Time

Evolution
Populations of organisms change or evolve
over time to adapt to an ever changing
world