Download What is Life Science?

TODAY ’ S O BJECTIVES :
•Nature of Science
•Scientific method
•Theories of modern biology
•Age of the Earth
•Evolution
•5 Kingdoms
•Characteristics of living things
W HAT
IS
S CIENCE ?

Science has the literal meaning of:
knowledge.

So, science is knowledge attained
through study or practice.
T YPES
OF
S CIENCE

Earth Science – environmental science,
geology, oceanography, palenotology.

Physics – astronomy, quantum mechanics,
thermodynamics.

Chemistry – biochemistry, organic chemistry,
thermochemistry.

Life Science – anatomy, botany, cell biology,
genetics.
W HAT
IS
L IFE S CIENCE ?

Life Science or Biology is “the
study of life”

Broad topic covering the minute
workings of chemical machines
inside our cells to global climate
changes.

Scientists have recently
deciphered the Human Genome
Project.
T HE S CIENTIFIC M ETHOD

Objective, logical, repitable

THE SCIENTIFIC METHOD
1.
Observation – defining a problem
2.
Hypothesis – possible explanation(s)
3.
Experimentation – tests hypothesis
4.
Conclusion – was hypothesis supported?
T HE B ASIS OF M ODERN
B IOLOGY

The Cell Theory

The Theory of Evolution by Natural Selection

Homeostasis
R OBERT H OOKE - C ELLS

Hooke was one of the first
scientists to use a
microscope.

Observed pond water, cork,
and other things to coin the
term CELLS, which as he
noted as the tiny cavities that
he saw.
T HE C ELL T HEORY

Coined by Schleiden and Schwann

The CELL THEORY
1.
All living things are made up of cells.
2.
Cells are the basic unit in living things.
3.
Cells reproduce to form new cells.
DNA

Watson and Crick were
the scientists involved in
representing DNA.

Crick later linked DNA
with proteins (the
Central Dogma,) which
explains the influence of
hereditary on an
organism.
H OMEOSTASIS

Maintenance of a dynamic range of
conditions within which an organism
can function.

Temperature, pH, energy, etc.
T HE A GE
OF THE
E ARTH

Radiometric dating,
which is a process of
dating, uses decay of
radiometric isotopes
to help determine
something's age.

Radiometric dating
suggests the Earth is
approximately 4.5
billion years old.
M ODERN V IEW OF
EVOLUTION

Carl Linneus attempted to categorize
living species of his time.

Created a hierarchy that is still used
today.

Based on a premise that the species
was the smallest unit and each species
belonged to a higher category.
LINNEAN TAXONOMY
Kingdom – Animalia
Phylum – Chordata
Class – Mammalia
Order – Primates
Family – Hominidae
Genus – Homo
Species - Sapiens
H OW SPECIES HAVE CHANGED

Jean Baptiste De Lamarck

Developed one of the first theories on how
species change.

He proposed that acquired characteristics
are inherited from generation to generation.
H OW SPECIES HAVE CHANGED

Charles Darwin

Got the opportunity to study adaptation which
would lead to his theory of evolution

He concluded:
1.
Adaptation – all organisms adapt to environment
2.
Variation – all organisms are variable in their traits.
3.
Over-reproduction – all organisms tend to reproduce
past their environments capacity.
4.
Natural selection – “best” variation advances
T HE D IVERSITY OF LIFE –-5 KINGDOMS
M ONERA

Most primative.

Uni-cellular.

Lack a nucleus and membrane bound
organelles. (PROKARYOTE)

Example – cyanobacteria or blue-green algae
P ROTISTA

First eukaryotic kingdom.

Have nucleus and membrane bound organelles.

This allows for organisms to compartmentalize or
give specific areas specific functions.

Chief role of Protista is being the stem group for
Plants, Animals, and Fungi

Example – ciliates, protozoa, flagellates.
F UNGI

Almost entirely Multicellular.

Heterotrophic – derive energy
from another organism.

Have an ecologic role of
decomposing and recycling
nutrients.

Economic role: food, medicine

Example – yeast, mushroom
P LANTAE

Multicellular.

Autotrophic – make own food
through photosynthesis.

Have an ecologic role as a producer
and sets the base of the food web.

Economic role: food, building
material, paper, medicine, drugs.
A NIMALIA

Multicellular, heterotrophic, capable of
mobility.

Ecologic role: consumers (herbivores,
carnivores, omnivores.)

Economic role: animal meat, clothes, pets.
C HARACTERISTICS OF L IVING
THINGS
1.
Composed of cells
2.
Organization
3.
Homeostasis
4.
Adaptation
5.
Reproduction and heredity
6.
Growth and development
7.
Metabolism
8.
Response to stimuli
Q UESTIONS TO THINK ABOUT
1.
Bacteria belong to which kingdom?
2.
What is the smallest unit of classification in
Linneus’ hierarchy?
3.
What scientists were associated with evolution
by natural selection?
4.
When an organism consists of a single cell it is
referred to as a ______________?
N EXT

TIME :
Chemistry: Atoms and molecules