All Living Things Share Common Characteristics Basic Unit is the

download report

Transcript All Living Things Share Common Characteristics Basic Unit is the

Study of
Characteristics
of Life
copyright cmassengale
Edited by pdunning EHS
1
What is Biology?
Biology is the study
of all living things
Living things are
called organisms
Organisms include
bacteria, protists,
fungi, plants, &
animals
2
All Living Things Share
Common Characteristics
1. Basic Unit is the Cell
2. They Reproduce
3. All Based On
Universal Genetic
Code (DNA)
4. Grow & Develop
3
Common Characteristics
5. Obtain & Use Materials &
Energy
6. Respond To Their Environment
7. Maintain A Stable Internal
Environment
8. AS A GROUP, Living Things
Evolve, That Is They Change
Over Time
4
Characteristics of Organisms
5
All Organisms are
made of Cells
6
Cell Structure and Function
Cell basic unit of life
All organisms are made
of and develop from
cells
Some composed of only
a single cell
(unicellular) which is
usually identical to
parent
Facts About Cells
Cells are the smallest living unit
of an organism
All cells contain cytoplasm
All cells are surrounded by a cell
membrane that controls what
enters & leaves the cell
8
More Cell Facts
Cells are complex &
highly organized
Cells have parts called
organelles that do
different jobs
e.g. Chloroplasts in
plants make sugars
9
More Cell Facts
The simplest cells are
called Prokaryotes
These cells DO NOT
have a nucleus or
membrane-bound
organelles
Bacteria are examples
10
More Cell Facts
More complex cells are
called Eukaryotes
These cells DO have a
nucleus and membranebound organelles
Plants, animals,
protists, & fungi are
examples
11
Organisms are Grouped by
their Number of Cells
Unicellular Organisms
– Living Organism Made Up Of One
Cell
Multicellular Organisms
– Living Organism Made Up Of
Many, Specialized Cells
12
Cells
All living things are
composed of cells
In multicellular
organisms, many are
specialized to perform
specific functions
Cells are always very
small
The size of multi-celled
organisms depends on
the number of cells
NOT their size
Copyright Cmassengale
13
Living things reproduce
Copyright Cmassengale
14
Organisms Reproduce to
Pass on their Genetic
Traits
15
Reproduction
 All species have the ability to reproduce
Not essential to survival of individual but
is essential for continuation of a species
Copyright Cmassengale
16
Two Types of Reproduction
Sexual
Reproduction
Involves 2 parents
Egg fertilized by
sperm to make a
ZYGOTE
Offspring
DIFFERENT from
parents
17
Two Types of Reproduction
Asexual
Reproduction
Involves a single
organism or cell
Cell divides
Offspring
IDENTICAL to
parent
18
Cells Have a Genetic Code
copyright cmassengale
19
Genetic Code
DNA (deoxyribose nucleic
acid) carries the genetic
code for all organisms
All organisms contain DNA
DNA codes for the
proteins that make up cells
& do all the work
necessary for life
20
Organisms Grow & Develop
21
Growth & Development
Organisms grow by
producing MORE
CELLS & by cell
ENLARGEMENT
Organisms develop as
they mature into an
adult organism
22
Growth
Grow occurs as the result of cell
division and cell enlargement
Cell division is the formation of
two cells from a preexisting cell
New cells enlarge as they mature
When a cell grows to a size
where its surface area isn’t big
enough for its volume, the cell
divides
Copyright Cmassengale
23
Cells Require Food & Energy
24
Food Requirements
Autotrophs can make
their own food
Photoautotrophs use
sunlight to make food
(photosynthesis)
Chemoautotrophs use
chemicals such as iron
& sulfur as their
energy
25
Food Requirements
Heterotrophs can NOT make their
own food
They must consume other
organisms
Herbivores eat plants
Carnivores eat meat
Omnivores eat plants & animals
26
All organisms need substances
such as nutrients, water, and
gases from the environment
The stability of the environment
depends on the healthy
functioning of organisms in that
environment
27
Metabolism
Sum of all the chemical reactions
in an organism
All require energy
Sunlight is the ultimate energy
for life on Earth
28
Metabolism
Cellular Respiration
– Cells releasing the chemical
energy stored in foods
6O2 + C6H12O6
6CO2 + 6H2O
29
Organisms Respond to Stimuli
Organisms Respond to stimuli
(Temperature, Water, Food
Supplies, etc.) In Order To
Survive & Reproduce
30
Homeostasis
Keeping The Internal Environment
(Homeostasis) Of The Cell or
Organism Within The Ranges Required
For Life
Stable internal conditions of pH,
temperature, water balance, etc.
31
Living Things Evolve
Groups Of Organisms
(Not Individuals)
Change Over Time In
Order To Survive
Within Changing
Environments.
Fossil records show
changes in groups of
organisms
32
Explains why organisms look and
behave the way they do
Provides a basis for exploring the
relationships among different
groups of organisms
33
Natural Selection
Natural selection is the
driving force in evolution
Organisms that have certain
favorable traits are better
able to successfully reproduce
than organisms that lack
these traits
34
Natural Selection
Survival of organisms
with favorable traits
cause a gradual change
in populations over many
generations
Copyright Cmassengale
35
Life is Organized on
Several Levels
36
Levels
Atoms
Molecules
Organelles
Cells – life starts here
Tissues
Organs
System
Organism
37
Levels
Population
Community
Ecosystem
Biosphere
38
39
Quiz Next Time!
40