Biology SOL
You CAN
Pass
Your
Biology
SOL!
Scientific Method
Step
1:
Make
an
OBSERVATION.
The
two
types
are:
→QUALITATIVE:
Descriptions
without
number.
(Ex)
The
book
is
heavy.
→QUANITATIVE:
Descriptions
that
use
numbers.
(Ex)
The
book
has
250
pages.
Step
2:
Make
a
HYPOTHESIS.
This
is
an
educated
guess
based
on
qualitative
and
quantitative
data.
⇒ Scientist
should
look
for
2
variables
in
trying
to
find
answers
to
the
problem.
◊INDEPENDENT
VARIABLE
(IV)
The
thing
I
change
◊DEPENDENT
VARIABLE
(DV)
The
thing
I
measure
Step
3:
Setup
a
CONTROLLED
EXPERIMENT.
Each
has:
1. CONTROL
GROUP:
the
group
that
stays
the
same
(doesn’t
receive
the
IV).
It’s
needed
to
compare.
2. EXPERIMENTAL
GROUP:
the
group
that
is
manipulated
(the
group
you
are
performing
the
experiment
on).
This
group
receives
the
IV.
Step
4:
Make
a
CONCLUSION
or
THEORY
⇒If
the
data
gathered
from
your
controlled
experiment
support
your
hypothesis,
you
accept
your
conclusion.
⇒If
the
data
doesn’t
support
your
hypothesis,
start
over!
How
to
Identify
Variables
on
a
Graph:
*****Scientists
use
the
SCIENTIFIC
METHOD
to
help
them
answer
questions
and
solve
problems
about
the
natural
world.***** ..................................................................................... .....................................................................................
Yaxis
is
the
DV.
The
thing
I
measure
Xaxis is
the
IV.
The
thing
I
change
*Water
makes
life
possible!
It’s
a
universal
solvent,
comes
in
three
states,
and
has
a
high
specific
heat
to
regulate
temperature*
The
chemical
formula
of
water
is
H2O.
It
has
2
hydrogen
and
1
oxygen.
Water
has
a
positive
side
(hydrogen)
and
a
negative
side
(oxygen).
These
charges
allow
water
to
stick
to
other
things
that
also
have
a
charge.
HYDROGEN
BONDS
hold
water
to
itself
and
to
other
charged
substances.
When
water
sticks
to
other
things
(like
a
car
window)
ADHESION
is
taking
place.
When
water
sticks
to
itself
COHESION
is
taking
place
Water
comes
in
3
states:
solid,
liquid
or
gas.
In
the
solid
state
(ice),
water
is
less
dense
than
the
liquid
state.
Ice
floats!
Water
has
a
HIGH
SPECIFIC
HEAT.
It
can
absorb
a
lot
of
energy
without
increasing
its
own
temperature.
This
is
why
water
takes
so
long
to
boil!
We
use
this
property
to
help
us
regulate
our
body
temperature.
When
our
body
temperature
gets
too
high,
we
start
to
PERSPIRE
(sweat).
We
do
not
want
our
body
temperature
to
fluctuate
very
much
because
it
would
alter
chemical
reactions
(METABOLISM).
When
metabolism
is
thrown
off,
HOMEOSTASIS
(balance)
is
also
Water & its Properties
..............................................................................
.............................................................................. thrown
off.
This
can
lead
to
death!!!!
pH Scale
Macromolecules
*All
living
things
are
composed
of
4
macromolecules.
Macromolecules
are
large
polymers
(the
prefix
“poly”
means
“many”)
that
are
composed
of
lots
of
smaller
building
blocks
called
monomers
(the
prefix
“mono”
means
“one”).
*
1. Carbohydrates:
The
only
macromolecule
that
is
used
for
ENERGY.
Carbohydrate
is
a
fancy
word
for
SUGAR.
The
most
important
sugar
is
GLUCOSE
(C6H12O6).
The
building
blocks
of
carbohydrates
are
MONOSACCHARIDES.
2. Lipids:
The
only
macromolecule
used
to
STORE
ENERGY
and
to
provide
INSULATION.
There
are
three
classes
of
lipids
(fats,
oils
&
waxes).
The
building
blocks
of
lipids
are
FATTY
ACIDS.
3. Proteins:
The
only
macromolecule
that
can
SPEED
UP
CHEMICAL
REACTIONS
and
provide
STRUCTURE
&
SUPPORT.
The
building
blocks
of
proteins
are
AMINO
ACIDS.
4. Nucleic
Acids:
The
only
macromolecules
that
TRANSMITS
HEREDITY
INFORMATION.
There
are
two
types
of
nucleic
acids:
DNA
&
RNA.
Their
building
blocks
are
NUCLEOTIDES.
...........................................................................................
Macromolecules
Enzyme
Enzymes
are
CATALYSTS.
Catalysts
SPEED
things
up!
Without
enzymes,
chemical
reactions
(metabolism)
would
happen
too
slowly
to
keep
you
alive.
Enzymes
are
shape
specific.
Enzymes
can
only
catalyze
reactants
(Substrates)
if
they
can
fit
inside
the
enzyme’s
ACTIVE
SITE.
Enzymes
speed
up
chemical
reactions
by
LOWERING
ACTIVATION
ENERGY.
Activation
energy
is
the
amount
of
energy
needed
to
start
a
chemical
reaction.
Activation
Energy
works
like
a
speed
bump.
• The
bigger
the
activation
energy
the
slower
the
chemical
reaction
• The
smaller
the
activation
energy
the
faster
the
chemical
reaction.
*Enzymes
are
biological
catalysts.
They
speed
up
chemical
reactions
and
regulate
metabolism.
Enzymes
are
proteins
that
can
lower
a
chemical
reaction’s
activation
energy*
Enzymes
...........................................................................................
Microscopy
*The
microscope
is
one
of
the
most
important
tools
in
biology.
It
allowed
scientists
to
discover
the
cell
and
all
of
its
structures.*
Once
the
microscope
was
invented,
ROBERT
HOOKE
was
able
to
see
and
name
the
tiny
structures
that
make
up
life
while
studying
cork.
He
was
the
first
person
to
use
the
word
CELL.
......................................................
The
are
only
2
things
that
you
need
to
Microscopes
&
the
Cell
know
about
microscopes:
1. Determining
Total
Magnification:
Multiply
the
eyepiece
(that
is
always
10x)
by
the
objective
lens
(the
lenses
that
can
be
rotated)
10
x
Objective
Lens=
Total
Mag.
2. Making
a
WetMount
Slide:
Always
place
the
cover
slip
on
at
a
45°
Angle
to
prevent
air
bubbles.
With
the
help
of
Hooke
and
other
scientists
working
with
the
microscope,
the
CELL
THEORY
was
created.
THE
CELL
THEORY:
1. All
living
things
are
composed
of
cells.
2. Cells
are
the
basic
units
of
structure
and
function
of
life.
3. Cells
can
only
come
from
pre‐
...............................................
existing
cells.
Cells: An Overview
All
living
things
are
made
up
of
only
one
of
two
type
of
cells:
PROKARYOTIC
CELLS
or
EUKARYOTIC
CELLS.
• Prokaryotes
are
simple,
small,
and
lack
a
nucleus.
The
only
example
of
a
prokaryote
is
BACTERIA.
• Eukaryotes
are
complex,
large,
and
contain
a
nucleus
and
lots
of
organelles.
All
protists,
fungji,
plants
and
animals
are
made
up
of
eukaryotic
cells.
****Everything
living
things
is
made
up
of
at
least
one
cell.
Cells
are
the
lowest
level
of
structure
of
living
things
that
can
still
perform
all
the
activities
(metabolism).**** ..........................................................................
Cell
of
Eukaryotes
Plant
Cell Animal
Cell
Cell Structures
...........................................................................
****Eukaryotes
contain
membrane‐bound
ORGANELLES.
Each
organelle
performs
a
specific
job
in
the
cell
to
help
maintain
metabolism
and
homeostasis.****
1. NUCLEUS:
This
is
the
control
center
of
the
cell.
It
contains
the
cell’s
DNA
and
controls
the cell’s
metabolism
and
homeostasis.
2. MITOCHONDRIA:
This
is
the
power
plant
of
the
cell.
The
cell’s
energy
supply
(ATP)
is
made
here
via
CELLULAR
RESPIRATION.
3. RIBOSOMES:
These
are
the
sites
of
protein
synthesis
for
the
cell.
4. GOLGI
APPARATUS:
This
is
the
post
office
of
the
cell.
It
packages
and
exports
materials
in
and
around
the
cell.
5. ENDOPLASMIC
RETICULUM:
There
are
two
kinds:
smooth
and
rough.
Both
help
to
move
things
around
the
cell.
They
work
like
a
system
of
roads
in
the
cell.
6. LYSOSOMES:
These
are
the
garbage
cans
of
the
cell.
They
break
down
waste.
7. CHLOROPLAST:
This
is
found
in
plants
and
is
the
site
of
photosynthesis.
8. CELL
WALL:
This
is
a
rigid
layer
found
on
the
outside
of
plant
cells.
It
gives
plant
cells
their
unique
rectangular
shape.
9. CELL
MEMBRANE:
This
surrounds
all
cells.
It
maintains
homeostasis
by
controlling
what
can
enter
and
leave
the
cell.
It’s
composed
of
two
layers
of
PHOSPHOLIPIDS.
The
PHOSPHOLIPID
BILAYER
has
a
polar
head
and
two
non‐polar
tails.
This
allows
things
that
are
small
and
nonpolar
to
cross
the
membrane
without
asking
for
permission.
Food
and
raw
materials
for
chemical
reactions
must
be
able
to
cross
the
membrane.
Waste
must
be
able
to
leave
the
membrane.
Cell Structures
Transport
****Substances
need
to
be
able
to
travel
into
and
out
of
cell
across
the
cell
membrane.
This
movement
can
either
happen
spontaneously
(by
itself)
or
with
the
input
of
energy
(ATP)****
There
are
two
types
of
transport:
PASSIVE
&
ACTIVE
1. PASSIVE
TRANSPORT:
This
moves
substances
across
membranes
from
regions
of
high
concentration
to
low
concentration
without
energy.
2. ACTIVE
TRANSPORT:
This
moves
substances
across
membranes
from
regions
of
low
concentration
to
high
concentration
with
energy
(ATP)
Examples:
Endocytosis
&
Exocytosis
..............................................................
There
are
3
types
of
PASSIVE
Transport:
1. DIFFUSION:
the
movement
of
substances
from
a
region
of
high
concentration
to
low
concentration.
2. OSMOSIS:
the
movement
of
water
from
a
region
of
high
concentration
to
low
concentration.
3. FACILITATED
DIFFISION:
the
movement
of
substances
from
high
to
low
with
the
help
of
a
transport
protein.
Metabolism
****CELLULAR
RESPIRATION
and
PHOTOSYNTHESIS
are
processes
that
allow
cells
to
use
and
make
energy
to
keep
the
cell
alive.
They
have
a
cyclical
relationship
with
one
another.
They
depend
on
one
another!****
Cellular
Respiration Photosynthesis
CELLULAR
RESPIRATION
is
a
process
that
turns
sugar
(glucose
C6H12O6)
into
usable
energy
for
the
cell
(ATP).
HETEROTROPHS
(organisms
who
cannot
make
their
own
food)
use
this
process
to
release
ATP
from
food
in
the
MITOCHONDRIA.
INPUT
(Reactants):
Mitochondria
take
in
oxygen
and
glucose
OUTPUTS
(Products):
Mitochondria
release
carbon
dioxide
and
ATP!!!!
PHOTOSYNTHESIS
is
a
process
that
turns
light
energy
from
the
sun
into
food
(glucose)
for
plants.
Plants
and
organisms
that
make
their
own
food
are
called
AUTOTROPHS.
Autotrophs
perform
photosynthesis
in
their
CHLOROPLASTS.
INPUT
(Reactants):
Chloroplasts
take
in
carbon
dioxide
and
sunlight.
OUTPUTS
(Products):
Chloroplasts
release
oxygen
and
glucose.
CO2 O2
Glucose
Chloroplast
Mitochondria
DNA
****DNA
is
a
double‐helix
composed
of
2
complementary
strands.
It
has
4
nucleotides
composed
of
either
A,
T,C,or
G:
A
pairs
with
T,
G
pairs
with
C.
This
structure
makes
DNA
REPLICATION
and
PROTEIN
SYNTHESIS
possible.!**** ..........................................................................
When
DNA
needs
to
divide,
DNA
REPLICATION
begins.
The
weak
hydrogen
bonds
that
are
holding
the
two
strands
of
DNA
together
break
apart
and
the
DNA
“unzips.”
The
two
original
strands
of
DNA
then
become
templates
for
new
daughter
strands
of
DNA
that
will
form.
Chromosome
Structure:
DNA (continued)
****The
process
of
turning
DNA
into
proteins
follows
a
specific
order.
It
starts
in
the
nucleus
and
ends
at
the
ribosome.****
Frst,
DNA
is
turned
into
MESSENGER
RNA
(mRNA).
RNA
is
the
skinny
cousin
of
DNA
which
means
it
can
leave
the
nucleus.
RNA
is
single‐stranded.
It
one
strand
looks
almost
identical
to
DNA
with
the
exception
of
the
nitrogen
base
URACIL.
Uracil
takes
the
place
of
thymine.,
so
U
pairs
with
A.
♦ Making
RNA
from
DNA
is
called
TRANSCRIPTION.
Next,
the
message
transferred
from
DNA
to
mRNA
makes
it
way
to
the
ribosome
(the
site
of
protein
synthesis).
♦ Making
proteins
from
mRNA
is
called
TRANSLATION.
Cell Division
****DNA
is
the
cell’s
genetic
material.
It
must
be
copied
before
the
cell
can
divide.
To
help
with
this,
the
DNA
is
packaging
into
structures
called
CHROMOSOMES.
Humans
have
46
chromosomes
that
must
be
copied
exactly
before
the
cell
can
divide.
The
process
of
cell
division
is
called
MITOSIS.
Mitosis
has
4
steps:
PROPHASE,
METAPHASE,
ANAPHASE
&
TELOPHASE.****
Genetics
****GENETICS
is
the
study
of
heredity.
A
GENE
is
a
basic
unit
of
heredity.
An
ALLELE
is
one
of
two
or
more
alternative
forms
of
a
specific
gene.
Two
alleles
make
up
a
gene.
GREGOR
MENDEL
crossed
peas
to
develop
the
genetic
theory
we
still
use.****
There
are
two
types
of
alleles:
‐DOMINANT
ALLELES:
The
expressed
trait.
Represented
by
a
capital
letter.
‐RECESSIVE
ALLELES:
The
unexpressed
trait.
Represented
by
a
lowercase
letter.
The
two
letters
(representing
two
alleles)
represent
an
organism’s
GENOTYPE.
There
are
two
types
of
genotypes:
‐HOMOZYGOUS:
two
identical
alleles
(TT)
or
(tt)
‐HETEROZYGOUS:
two
different
alleles
(Tt)
The
expression
of
the
genotype
(physical
appearance
of
the
gene)
is
the
PHENOTYPE.
We
can
use
the
parent
genotypes
to
predict
what
offspring
might
look
like.
Monohybrid
crosses
can
be
completed
by
using
a
PUNNET
SQUARE.
......................................................................................
Example
of
a
monohybrid
cross:
Consider
a
cross
between
a
true
breeding
tall
plant
(TT)
and
a
true
breeding
short
plant
(tt).
Classification
****All
of
life
can
be
classified
in
one
of
6
kingdoms.
Each
kingdom
can
be
broken
down
into
even
smaller
units
for
classification.
The
modern
day
classification
system
is
based
on
a
two‐word
naming
system
called
BINOMIAL
NOMENCLATURE.
This
naming
system
involves
an
organism’s
GENUS
and
SPECIES.****
...........................................................
The
6
kingdoms
of
the
life
are:
1. Archaebacteria:
Prokaryotic
organisms
that
are
only
found
in
extreme
environments.
2. Eubacteria:
Single‐celled,
prokaryotic
organisms
that
can
cause
sickness
(Example:
streptococcus
&
salmonella)
3. Protist:
Single‐celled,
eukaryotic
organisms
that
can
be
either
heterotrophic
(protozoa)
or
autotrophic
(algae).
4. Fungi:
Multicellular
eukaryotic
organisms
with
cell
walls
composed
of
chitin.
These
organisms
are
external
digesters
(heterotrophic).
5. Plant:
Multicellular
eukaryotic
autotrophs
with
cell
walls
composed
of
cellulose.
6. Animal:
Multicellular
eukaryic
heterotrophs
that
do
not
have
cell
walls.
Evolution
****EVOLUTION
is
the
process
by
which
species
change
over
time.
It’s
brought
on
by
the
process
of
NATURAL
SELECTION.
Natural
selection
allows
for
individuals
with
certain
traits
to
successfully
survive
and
reproduce,
passing
those
traits
to
the
next
generation.****
SPECIATION
is
the
process
by
which
new
species
arise.
There
are
two
mechanisms
that
can
lead
to
new
species:
o Geographic
Isolation:
the
physical
separation
of
species
populations
by
geographic
barriers
(Example:
oceans
and
mountains)
o Reproductive
Isolation:
Isolation
WITHOUT
the
presence
of
a
physical
barrier.
(Example:
One
group
of
individuals
only
mates
in
the
fall,
and
another
only
reproduces
in
the
spring.)
...............................................................
A
SPECIES
is
a
group
of
individuals
that
can
interbreed
and
produce
fertile
offspring.
‐The
horse
and
zebra
are
both
members
of
their
own
species.
How
do
we
know?
When
we
force
them
to
mate,
their
off‐
spring
(a
zebroid)
is
not
fertile.
Evidence
for
Evolution
****Scientists
have
3
areas
of
focus
that
provide
evidence
for
evolution.****
1.
Fossils 2.
Anatomy 3.
Biochemistry
Scientists
can
use
layers
of
undisturbed
rock
to
determine
the
relative
age
of
fossilized
organisms.
The
OLDEST
fossils
will
always
be
at
the
bottom
of
the
column
and
the
YOUNGEST
at
the
top.
This
technique
is
called
the
PRINCIPLE
OF
SUPERPOSITION.
.........................................................................
HOMOLOGOUS
STRUCTURES:
Structures
that
look
SIMILAR
to
one
another.
These
demonstrate
descent
from
a
COMMON
ANCESTOR
(Divergent
Evolution)
ANALOGOUS
STRUCTURES:
Different
structures
that
perform
similar
functions.
The
environment
forces
unrelated
individuals
to
develop
structures
to
perform
similar
function.
NO
COMMON
ANCESTOR!
(Convergent
Evolution)
Remember:
Organisms
that
have
more
DNA
in
common
are
closely
related!
This
means
that
organisms
that
have
more
proteins
in
common
are
also
closely
related.
Look
at
the
amino
acid
chain
of
unknown
animal:
MetGlySerTyrTyrArgHisHisGluLys
It
most
closely
resembles?
Horse:
Met‐Gly‐Ser‐Ser‐Tyr‐Arg‐Arg‐Asp‐His‐Glu
Dog:
Met‐Gly‐Ser‐Tyr‐Tyr‐Arg‐His‐Asp‐Glu‐Lys
Cat:
Met‐Gly‐Ser‐Tyr‐Tyr‐Arg‐His‐His‐Arg‐Cys
Mouse:
Met‐Gly‐Ser‐Tyr‐Tyr‐Arg‐His‐Glu‐Val‐Val
Our
unknown
animal
is
most
closely
related
to
the
dog!
There’s
only
1
difference
in
the
protein
sequence.
Met‐Gly‐Ser‐Tyr‐Tyr‐Arg‐His‐Asp‐Glu‐Lys