Study of Biology
copyright cmassengale
1
What is Biology?
Biology is the study of all living
things
Living things are called
organisms
Organisms include bacteria,
protists, fungi, plants, & animals
copyright cmassengale
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
copyright cmassengale
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
copyright cmassengale
4
Characteristics of Organisms
copyright cmassengale
5
All Organisms are
made of Cells
copyright cmassengale
6
Facts About Cells
Cells are the smallest living unit
of an organism
All cells contain living material
called cytoplasm
All cells are surrounded by a cell
membrane that controls what
enters & leaves the cell
copyright cmassengale
7
More Cell Facts
Cells are complex &
highly organized
Cells have parts called
organelles that do
different jobs
e.g. Chloroplasts in
plants make sugars
copyright cmassengale
8
More Cell Facts
The simplest cells are
called Prokaryotes
These cells DO NOT
have a nucleus or
membrane-bound
organelles
Bacteria are examples
copyright cmassengale
9
More Cell Facts
More complex cells are
called Eukaryotes
These cells DO have a
nucleus and membranebound organelles
Plants, animals,
protists, & fungi are
examples
copyright cmassengale
10
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
copyright cmassengale
11
Organisms Reproduce to
Pass on their Genetic
Traits
copyright cmassengale
12
Two Types of Reproduction
Sexual
Reproduction
Involves 2 parents
Egg fertilized by
sperm to make a
ZYGOTE
Offspring
DIFFERENT from
parents
copyright cmassengale
13
Two Types of Reproduction
Asexual
Reproduction
Involves a single
organism or cell
Cell divides
Offspring
IDENTICAL to
parent
copyright cmassengale
14
Cells Have a Genetic Code
copyright cmassengale
15
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
copyright cmassengale
16
Organisms Grow & Develop
copyright cmassengale
17
Growth & Development
Organisms grow by
producing MORE
CELLS & by cell
ENLARGEMENT
Organisms develop as
they mature into an
adult organism
copyright cmassengale
18
Cells Require Food & Energy
copyright cmassengale
19
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
copyright cmassengale
20
Food Requirements
Heterotrophs can NOT make their
own food
They must consume other
organisms
Herbivores eat plants
Carnivores eat meat
Omnivores eat plants & animals
copyright cmassengale
21
Metabolism
Sum of all the chemical reactions
in an organism
All require energy
Sunlight is the ultimate energy
for life on Earth
copyright cmassengale
22
Metabolism
Cellular Respiration
– Cells releasing the chemical
energy stored in foods
6O2 + C6H12O6
6CO2 + 6H2O
copyright cmassengale
23
Organisms Respond to
Stimuli
Organisms Respond to stimuli
(Temperature, Water, Food
Supplies, etc.) In Order To
Survive & Reproduce
copyright cmassengale
24
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.
copyright cmassengale
25
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
copyright cmassengale
26
Life is Organized on
Several Levels
copyright cmassengale
27
Levels
Atoms
Molecules
Organelles
Cells – life starts here
Tissues
Organs
System
Organism
copyright cmassengale
28
Levels
Population
Community
Ecosystem
Biosphere
copyright cmassengale
29
copyright cmassengale
30
copyright cmassengale
31