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Tackle the
Science TAKS
Why study this?
•You have slept a few hundred
times since you took biology.
•We believe that you need an
intensive review.
Why are you here?
TAKS Test Information
30% Nature of Science
Graphs, Scientific Method, & Safety
15% Living systems
Cells, Genetics, & Taxonomy
15% Environment
Cycles, Pyramids, Chains, & Webs
20%
Properties of Mater
Atoms, Molecules, & Elements
20% Physics
Motion, Forces, & Energy
Nature of Science?
a.k.a. “Can You Look at Pictures
and Read a Graph?”
age of population (millions)
100
total #
80
60
Series1
40
Which graph is
better at showing
the information?
20
10
0's
90
's
80
's
70
's
60
's
50
's
40
's
30
's
20
's
ns
te
e
0
-1
0
0
decades
What’s on the “X” axis?
age of population (millions)
0 - 10
teens
20's
30's
40's
50's
60's
What is it telling you?
70's
80's
90's
100's
1. Many doctors recommend 800 μg of folate, 400 μg of
vitamin B12, and 50 mg of vitamin B6 per day
to improve cardiovascular health. Based on
this information and the nutrition label, the
cardiovascular health benefit of a 1-ounce
serving of this cereal is —
?
A doubtful because it provides insufficient folate and
vitamin B6 and lacks vitamin B12
B superb because it contains only 22 g of
carbohydrates and 75 mg of sodium
C excellent because it provides all needed vitamins
and is low in fat and cholesterol
D poor because it raises blood cholesterol levels with
its high fat and cholesterol content
Hint: Does the question talk about carbohydrates, fats
and sodium? – ELIMINATE!!
Scientific Method
Steps:
1. Questions:
2. State a Hypothesis:
“I think”, “If…, Then…”, “Cause and Effect”
3. Test or Experiment:
How you know if your right, or wrong?
4. Collect Data:
All experiments provide data.
5. Conclusion:
Validate, or restate
Cell and Cell Structures
Cells are: smallest biological unit
that can sustain life.
Two different types of Cells
Prokaryotes
pronounced (pro-carry-oats)
Pro = before
Karyo = kernel or seed
“Before the Nucleus”
Prokaryotic cells are
one where the genetic
material is not
contained in a nucleus.
The DNA is just floating in the cell in
a ring called a Plasmid.
Best Example
– E-coli bacteria in your gut
EuKaryotes pronounced (you-carry-oats)
Eu = true
Karyo = kernel or seed
“True Nucleus”
Eukaryotes have genetic
material stored in the nucleus.
They are:
•generally bigger
•have organelles
•may live in multi-cellular units
Best example - You
Diffusion:
Things moving
from high
concentration to
low
concentration.
Things will diffuse until they reach Equilibrium
Osmosis:
Water moving across a membrane to equalize
another molecule’s concentration.
Example:
A substance (solute) is placed in a
beaker that is divided by a semipermeable membrane.
When a molecule can’t move
across a membrane to equalize
concentration, Water will!
Water will move to equalize the
concentration.
DNA = DeoxyriboNucleic Acid
What is it made from?
Nucleotides:
Phosphate group
Ribose (5 carbon) sugar
Nitrogen Base
Groups of Nucleotides
Purines
Adenine
Guanine
Pyrimidines
A
G
T
C
Thymine
Cytosine
Pairing Rule
1. Adenine always bonds with Thymine
2. Guanine always bonds with Cytosine
How do they link up?
One Nucleotide links with the
next one in the chain by a
COVALENT bond between
the ribose and the next
nucleotides phosphate
The opposite side goes in the other
direction, linking across the
nitrogen base by HYDROGEN
bonds
How do cells make new copies of DNA for new cells?
Replication:
1. When DNA needs to be copied,
it unwinds in the nucleus
2. An enzyme, DNA Helicase,
starts to “unzip” the DNA
making a replication fork.
3. As DNA is unzipped, another
enzyme, DNA Polymerase,
begins to add nucleotides to
the now exposed bases of the
old strand.
4. The two new DNA strands
recoil.
DNA making DNA
DNA makes RNA,…….. But How?
Transcription: DNA making RNA
1. DNA unwinds and unzips.
2. The RNA Polymerase
attaches to a Initiation site.
3. The RNA Polymerase
begins to move only on one
(1) of the strands adding
RNA nucleotides
4. When reaching a
termination site, the RNA
Polymerase releases the
DNA and goes to make
more RNA
Transcription occurs in the nucleus, but the
Messenger RNA (mRNA) leaves the nucleus.
It attaches to a
Ribosome which
begins to read the
mRNA
It reads three (3) letter
words called Codons
Example: An mRNA that attaches to the Ribosome
A
c
u
a
a
a
g
c
g
u
a
u
g
c
a
It reads ACU, then it moves down and reads AAA and so on…
The process of reading the
mRNA code and making
Proteins is called:
Translation
The Ribosome doesn’t
just read the mRNA, it
calls for Amino Acids for
each Codon it reads.
The codon “U G C” calls for
the amino Acid Cysteine.
U
G
C
Hey! I need
a Cysteine!!
A little help
here?
Help comes from
another type of
RNA:
tRNA
U
G
C
A
C
G
Transfer RNAs have a
group of three bases
called the “anticodon”
that is the compliment of
the mRNA
Each TRNA carries a
different Amino Acid:
ACG carries Cysteine
Cysteine
The Ribosome
moves down the
mRNA and calls
for the next
Amino Acid
The first tRNA
goes away when
the second amino
acid is attached
to the first with a
Peptide bond
Then the ribosome
moves to the next
Codon
U
G
C
A
C
G
Cysteine
A
U
C
G
G
C
Threonine
Cell Division
Cells divide for two reasons.
1. To create copies Mitosis
2. To create sex cells -
Meiosis
Mitosis
4 stages:
1. Prophase:
The Centrioles begin to move apart.
Chromosomes thicken
The Nuclear membrane disappears
2. Metaphase:
The centrioles are at the “poles” of the cell
The chromosomes line up in the middle
of the nucleus
3. Anaphase:
The Chromosomes are pulled toward the
centrioles by spindle fibers
4. Telophase:
The nucleus begins to reform and the
cell begins cytokinesis
Meiosis:
The process of creating haploid
sex cells called Gametes
Gamete - sperm or egg
Has two “phases” of
“Mitosis-like stages”
For humans, it takes a
cell with 46
chromosomes and
makes cells with 23.
Let’s look at some Genetic traits
DOMINANT
Black color This dog’s genetics could be two ways
We show the genetics like this:
“B” from one parent, “B” from the other parent
OR
“B” from one parent, “b” from the other parent
“BB” is Homozygous for the trait.
“Bb” is Heterozygous for the trait.
Recessive
lighter color This dog’s genetics CAN ONLY be
shown one way:
“b” from one parent, “b” from the other parent
Recessive traits are ALWAYS
homozygous; thus it would be “bb”
OK, now for a problem:
If I have a
heterozygous black
male and a golden
femalewhat
that ismate,
the chances
of having golden
Bb
puppies in the litter? 50% black
X
bb
100%
golden
50% golden
You either multiply it out or make a Punnett square
Or
b
b
B
Bb
Bb
b
bb
bb
50%
EVOLUTION
Darwin’s Theory - Natural Selection
Those organisms that are best “fit” to the
environment will survive the environment.
Adaptation – a characteristic that an organism
has that allows it to survive.
Extinction – all members of a population dying
out due to not having beneficial
adaptations.
What Evidence is there for Natural
selection?
1. The Fossil Record
Fossils found at lower
layers of rock are
more simple than
those found at upper
layers.
2. Homologous Structures.
Structures from one creature are similar to the
structures from other creatures.
3. Vestigial Organs
Organs that are found in you that have no purpose
in the body, but are found and used in other
organisms.
1. You have an appendix.
2. Snakes have hipbones. 
3. Whales have
hipbones too.
4. Missing Links
There are missing links in the fossil record that
show that the species that are in the earth today.
Rhodocetus – Whale-like species
with limbs.
Archaeopteryx – ancient bird-like
reptile with wings, and
feathers. But it has teeth
and claws on the
forelimbs.
Sometimes change is directional
Directional Selection:
This happens when one of the “extremes” is favored
in an environment over the other extreme or the old
average.
Stabilizing Selection:
Then the average is favored over either of the
extremes in a population.
Disruptive Selection:
This situation happens when either extreme is favored
over the average.
Virus and Bacteria
Virus:
Non-living
Parasitic
Biological Particle
Viruses do not “live”
because they can not
reproduce outside a
“host” cell.
Host: - any organism that is used by a virus
or bacteria to complete it’s lifecycle
Bacteria!!!!
Prokaryotic cells
Living cells!
Bacteria come in three shapes.
Spirilla – corkscrew
shaped
Bacilli – rod
shaped
Cocci - spherical
shaped
Classification
Carolus Linnaeus created a system that allowed scientist
all over the world to name the species
that were discovered
Kingdom – broadest classification King
Phylum – separates into major groups
within the Kingdom (plural – phyla)
Phillip
Class – breaks phyla into smaller groups
Came
Order – more specific
Family – very similar characteristics
Genus – a reproductive grouping
Species – most specific
Over
For
Good
Soup
How are animals put into the taxonomic
categories?
They used to be put in by looks
(physical Characteristics).
That can
cause
problems!
Black Bear
Panda (not bear)
Phylogeny - the study of evolutionary
relationships
Cladogram
- a way to visually show relationships
between organisms.
Two examples
Now organisms are organized
by similarities in their DNA.
Types of Kingdoms
1. Animalia
- heterotrophic
multi-cellular
no cell walls
(there are 6 different kingdoms)
2. Plantae
-Autotrophic
multi-cellular
with cell walls
3 Fungi
- Heterotrophic
multi-cellular
with cell wall
4 Protista
-Heterotrophic or autotrophic
single cellular Eukaryotic
with or without cell walls
5. Bacteria
- heterotrophic or autotrophic
single cellular
prokaryotic
with cell walls
6. Archaebacteria
-Heterotrophic or autotrophic
single cellular
prokaryotic
with cell walls
live in extreme environments
Ecology
The study of interactions between
living things and their environment
Levels in Ecology
1. Individual A single member
of a species
2. Population A group of individuals
of a species.
3. Community Several species in
an area.
4. Ecosystem Living and nonliving
things in an area
5. Biome
Group of ecosystems
6. Biosphere All the biomes
How do organisms interact?
Producers - organisms that
produce their own
energy, and are
food for other
organisms.
They are also called
autotrophs
Consumers - organisms that
have to eat other
organisms for
their energy
They are also called
heterotrophs
Who eats who?
Food Chain - a series of steps showing which organisms
eat which. (transfer energy)
Food Web
- a chart linking all
food webs in a
particular area
Another way to show relationships
Ecological Pyramids
Biomass Pyramid
- each level in the
pyramid shows the total
amount of organisms in
the level
Numbers Pyramid
- each level shows the
numbers of individuals
in the pyramid
Energy Pyramid
- each transition shows
the amount of loss of
energy from one level to
the next.
90% of energy
is lost to heat
from one level to
the next.
Only 10% of your food is actually incorporated
into making you!
Cycles in Nature
Water Cycle - shows the different stages that water goes
through in ecology
Carbon Cycle
- the carbon that makes you and all other
living (and many non living) things is
shown moving through the environment.
Nitrogen Cycle - All organisms require nitrogen. This cycle
shows how it moves through the environment.
Biotic factors in the environment interact in many
ways
Competition
When groups are
using limited
resources Situation
leaves winners and
losers.
Predation
When one organism
feeds on another
They can form a symbiotic relationship
(three different types)
1. Mutualism
Both individuals
benefit.
2. Commensalism
One is helped, one is
neither helped or harmed.
3. Parasitism
One is helped, the other is
harmed.
Biomes:
Def: a large area that is characterized by certain
soil, climate. plants, and animals.
Chemistry
The Basics
Matter – Anything that has
mass and takes up space
Substances –
Cannot be broken
down Physically
Mixtures –
physical
combination of
two or more
substances
Substances
Compounds
Elements
• Cannot be broken • Chemical combination
of two or more elements
down any farther
• Requires a chemical
• Found on the Periodic reaction to separate
Table
IA
A
H
II A
Li
Be
Na
VIII
III
B
IV
Al
Si
N
1s1
P
1s1
As
1s1
Sb
1s1
Bi
O
1s1
Si
1s1
Se
1s1
Te
1s1
Po
V
Cr
Mn
Fe
Co
Ni
Cu
Zn
Ga
Ge
Rb
Sr
Y
Zr
Nb
Tc
Ru
Rh
Pd
Ag
Cd
In
Sn
Cs
Ba
La
Hf
Ta
M
o
W
Re
Os
Ir
Pt
Au
Hg
Tl
Pb
Rb
Ra
Ac
Rf
Db
Sg
Bh
Hs
Mt
5f1
5f2
5f3
5f4
4f5
5f5
4f6
5f6
I
C
Ti
4f4
VIII
B
K
4f3
VII
VI
M
g
Ca
4f2
VI
V
III
II
Sc
4f1
V
IV
4f7
5f7
4f8
5f8
4f9
5f9
4f10
5f10
VII
F
1s1
Cl
Ne
1s1
Ar
Br
Kr
I
Xe
At
Rn
4f1
4f1
4f1
4f1
1
2
3
4
1
2
3
4
5f1
5f1
5f1
He
5f1
Mixtures
Homogeneous
• Uniformly mixed
– Like soda
Heterogeneous
• Unevenly mixed
– Like tossed salad
Properties of matter
Physical
Chemical
• Describes how
• Describes how
something looks or feels something acts (or
reacts)
• Observed using the
senses
• Observed through
– Example: color, texture, chemical reactions
– Examples: being
• States of matter are
flammable, iron will
physical properties
rust
Physical Properties
•
• Intensive
• Do not depend on how •
much of something you
have
•
• Examples: color,
shape, density
Extensive
Does depend on how
much you have
Examples: mass,
volume,
Changes in Matter
Physical
Chemical
• Any change that does not alter the •
chemical make up of a substance
• Example:
– Tearing paper
•
– Boiling water
– Melting iron
• There are three main states of
matter: solid, liquid, gas
– Changing from one state to
another is a physical change
does not change the substance
Any change in matter that
does alter the chemical
composition of a substance
Examples:
– Burning wood
– Vinegar and baking soda
– Rusting iron
The Atom
• The atom is the smallest part of an element that still retains the
properties of that element.
• All atoms are made up of three subatomic particles
– Protons
• Positive charge
• Located in nucleus
• Mass of 1
– Neutrons
• No charge
• Located in nucleus
• Mass of 1
– Electrons
• Negative charge
• Located in electron cloud surrounding nucleus
• Mass of 0
The Atom
• An element is defined by the
number of PROTONS it has
• Protons + Neutrons + Mass.
• In a neutral atom, the number of
protons and electrons is the same
•Atoms of the same element
can differ in the number of
electrons or the number of
neutrons
Isotopes
•Atoms of the same
element with different
numbers of neutrons
are called isotopes.
•In isotope notation
(carbon-14) the
number tells the total
atomic mass.
IONS
•Atoms of the same element with
different numbers of electrons are
called ions
•The charge of an ion is always
written as a superscript (Na+1)
•If an ion has a positive charge, then
it has LOST electrons
•If an ion has a negative charge,
then it has GAINED electrons
The Periodic Table
IA
A
H
II A
Li
Be
B
III
IV
V
VI
VII
VIII
I
III
IV
V
B
C
Al
Si
N
1s1
P
1s1
As
1s1
Sb
1s1
Bi
II
Na
Mg
K
Ca
Sc
Ti
V
Cr
Mn
Fe
Co
Ni
Cu
Zn
Ga
Ge
Rb
Sr
Y
Zr
Nb
Mo
Tc
Ru
Rh
Pd
Ag
Cd
In
Sn
Cs
Ba
La
Hf
Ta
W
Re
Os
Ir
Pt
Au
Hg
Tl
Pb
Rb
Ra
Ac
Rf
Db
Sg
Bh
Hs
Mt
VIII
VI
O
1s1
Si
1s1
Se
1s1
Te
1s1
Po
VII
He
F
1s1
Cl
Ne
1s1
Ar
Br
Kr
I
Xe
At
Rn
4f1
4f2
4f3
4f4
4f5
4f6
4f7
4f8
4f9
4f10
4f11
4f12
4f13
4f14
5f1
5f2
5f3
5f4
5f5
5f6
5f7
5f8
5f9
5f10
5f11
5f12
5f13
5f14
The periodic table organizes the elements by
their chemical properties and reactivity.
The Periodic Table
IA
A
H
II A
Li
Be
B
III
IV
V
VI
VII
VIII
I
III
IV
V
B
C
Al
Si
N
1s1
P
1s1
As
1s1
Sb
1s1
Bi
II
Na
Mg
K
Ca
Sc
Ti
V
Cr
Mn
Fe
Co
Ni
Cu
Zn
Ga
Ge
Rb
Sr
Y
Zr
Nb
Mo
Tc
Ru
Rh
Pd
Ag
Cd
In
Sn
Cs
Ba
La
Hf
Ta
W
Re
Os
Ir
Pt
Au
Hg
Tl
Pb
Rb
Ra
Ac
Rf
Db
Sg
Bh
Hs
Mt
VIII
VI
O
1s1
Si
1s1
Se
1s1
Te
1s1
Po
VII
He
F
1s1
Cl
Ne
1s1
Ar
Br
Kr
I
Xe
At
Rn
4f1
4f2
4f3
4f4
4f5
4f6
4f7
4f8
4f9
4f10
4f11
4f12
4f13
4f14
5f1
5f2
5f3
5f4
5f5
5f6
5f7
5f8
5f9
5f10
5f11
5f12
5f13
5f14
On this table, the colors show the groups
(families). Elements in the same column
have similar chemical properties.
The Periodic Table
IA
A
H
II A
Li
Be
B
III
IV
V
VI
VII
VIII
I
III
IV
V
B
C
Al
Si
N
1s1
P
1s1
As
1s1
Sb
1s1
Bi
II
Na
Mg
K
Ca
Sc
Ti
V
Cr
Mn
Fe
Co
Ni
Cu
Zn
Ga
Ge
Rb
Sr
Y
Zr
Nb
Mo
Tc
Ru
Rh
Pd
Ag
Cd
In
Sn
Cs
Ba
La
Hf
Ta
W
Re
Os
Ir
Pt
Au
Hg
Tl
Pb
Rb
Ra
Ac
Rf
Db
Sg
Bh
Hs
Mt
VIII
VI
O
1s1
Si
1s1
Se
1s1
Te
1s1
Po
VII
He
F
1s1
Cl
Ne
1s1
Ar
Br
Kr
I
Xe
At
Rn
4f1
4f2
4f3
4f4
4f5
4f6
4f7
4f8
4f9
4f10
4f11
4f12
4f13
4f14
5f1
5f2
5f3
5f4
5f5
5f6
5f7
5f8
5f9
5f10
5f11
5f12
5f13
5f14
All Elements to the LEFT of the stair step line
(red line) are metals.
Elements to the RIGHT are nonmetals.
Elements that are touching the line are
called metalloids or semi-metals
The Periodic Table
IA
A
H
II A
Li
Be
B
III
IV
V
VI
VII
VIII
I
III
IV
V
B
C
Al
Si
N
1s1
P
1s1
As
1s1
Sb
1s1
Bi
II
Na
Mg
K
Ca
Sc
Ti
V
Cr
Mn
Fe
Co
Ni
Cu
Zn
Ga
Ge
Rb
Sr
Y
Zr
Nb
Mo
Tc
Ru
Rh
Pd
Ag
Cd
In
Sn
Cs
Ba
La
Hf
Ta
W
Re
Os
Ir
Pt
Au
Hg
Tl
Pb
Rb
Ra
Ac
Rf
Db
Sg
Bh
Hs
Mt
VIII
VI
VII
O
1s1
Si
1s1
Se
1s1
Te
1s1
Po
He
F
1s1
Cl
Ne
1s1
Ar
Br
Kr
I
Xe
At
Rn
4f1
4f2
4f3
4f4
4f5
4f6
4f7
4f8
4f9
4f10
4f11
4f12
4f13
4f14
5f1
5f2
5f3
5f4
5f5
5f6
5f7
5f8
5f9
5f10
5f11
5f12
5f13
5f14
The groups are named as follows:
Alkali metals
Transition metals
Halogens
Alkaline-earth metals
Inner-transition metals
Noble gases
Chemical Bonds
A Chemical bond is the force that holds two atoms
together
Bonds form so that atoms can be stable.
An atom is stable when it has eight valence
(outside) electrons
The noble gases have eight valence electrons and
therefore do not react with other elements
The Two types of chemical bond are:
Ionic Bonds
Covalent Bonds
Ionic Bonds
• Formed when one atoms
gives up electrons and
another one takes them
• Called ionic because ions
are formed
• Form crystals in solid form
• Have much higher melting
and boiling points
Example : NaCl……. Table salt
Covalent Bonds
• Formed when one atom
shares it electron with
another
• The word “covalent”
means “outsides
together”
• Generally do not form
crystals
• Have lower boiling and
melting points
Example: H2O ….. Water
Chemical Reactions
How do you know a chemical reaction has
happened?
1.It gives off light (flames are a good sign)
2.It gives off or absorbs heat (again with the
flames)
3.It changes colors (unexpectedly)
4.Produces a gas (usually observed as
bubbles or fizz)
5.Produces a precipitate (a solid formed
from two liquid reactants)
What are the different types of chemical
reactions?
1. Synthesis – only one product from more
than one reactant
2. Decomposition – more than one
product from only one reactant
3. Single replacement – an element
replaces one element in the other
reactant
4. Double replacement – The two
compounds that react trade partners
5. Combustion – must have oxygen,
usually gives off a large amount of heat
Chemical Equations
A chemical equation uses symbols and
chemical formulas to represent what
happens in a chemical reaction. They
look like the following:
1 CaSO4 + 2 LiOH  1 Li2SO4 + 1 Ca(OH)2
Reactants
Products
Subscripts
Coefficients