Transcript Biology Midterm Exam Review

Biology Unit Exam Review
Microscope
Total Magnification= eyepiece X
objective
1. 10 X 40= 400
2. High Power
Key Terms for Microscope
3.
Magnification: see first slide for total
magnification
4. Resolution: show two points that are
close together as separate images
5. Slide moves to left, image appears
to move to the right
Parts of the Microscope
1.
2.
3.
4.
5.
6.
7.
8.
Ocular/Eyepiece
Fine Adjustment Knob
Objective Lenses
Diaphragm
Base
Light Source
Stage
Arm
Fine vs Coarse Adjustment
 7.
Course Adjustment Knobmoves lenses
 8. Course- low power
 Fine-
High Power
MAKE SURE THAT YOU KNOW
THE DIAGRAM OF THE
MICROSCOPE AND THE
CHARACTERISTICS OF LIFE
Scientific Method
Steps of Sci Method:
Problem
Hypothesis
Testing Hypothesis (procedure)
Record Data (# or details)
Analyze and Form Conclusions
Replicate Work
Variables
Controlled Experiment:
Two groups differ by one factor;
control is present
Control vs Experimental Group:
Experimental group has something
changed (i.e. amount of light, etc)
Variables
Independent Variables:
Changed by scientist to see what
happens
Dependent Variable: Changes in
response to the change the scientist
makes to the independent variable.
Determine the Different Variables
 Does
fertilizer make a plant grow?
 Two
spider plants are placed in
separate pots. One plant is given
fertilizer and the other plant is not.
Both plants are measured daily.
 Identify
Independent, Dependent,
and control group
Answers

INDEPENDENT: Amount of fertilizer
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DEPENDENT: Growth of plant

CONTROLLED: Plant not receiving fertilizer
Chemistry
Atomic Number, Atomic Mass
Atomic #: # of protons in the
nucleus
Atomic Mass: sum of protons
and neutrons in the nucleus
Example: Oxygen
Atomic #: 8
Atomic Mass: 16
Determine the # of protons,
neutrons, and electrons
ANSWER
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Protons: 8
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Electrons: 8

Neutrons: 16-8= 8
Charges
Protons: +
Electons: Neutrons: neutral
Neutral Atom
Neutral atom has no charge; so
number of protons and
electrons would be equal
Ions
 Charged
 Charge
atom
can be either positive
or negative…how does this
form?
ANSWER
 Positive
Ion: excess positive
charge ( more protons)
 Negative
Ion: excess negative
charge (more electrons)
Positive or Negative Ion?
Isotope of potassium has 19
protons and 21 electrons.
What is its charge?
ANSWER

NEGATIVE
Covalent Bonds
Bond formed by sharing
electrons
Ionic Bond
Bond that forms by transferring
the electrons; can create an
electrical attraction
Elements, Compound, Mixture
Elements: substance made up of one kind of
atom (i.e. oxygen)
Compound: made up of two or more
elements (i.e. water)
Mixture: substances that are mixed without
forming a new chemical bond (i.e.
saltwater)
2H2O + O2---2H2O2
Atoms= hydrogen, oxygen
Reactants: 2H2O + O2
Products: 2H2O2
Atoms: 8 Hydrogen, 8 Oxygen
Chemical Formula
Tells you the type and amount of
atoms
EX: H2SO4
2 hydrogen, 1 sulfur, and 4 oxygen
H2SO4

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
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Atoms: Hydrogen, Sulfur, Oxygen
H= 2
S=1
O=4
pH Scale
 pH
runs from 1-14
 7 is neutral
 Below 7 acidic (with 1 being
more acidic)
 Above 7 basic with 14 being
most basic
Neutralization Reaction


Reaction that occurs when acids and bases are
combined to form water and salt
EX: NaOH + HCl----NaCl + H2O
Solution & Its Parts

Substances are spread evenly throughout the
mixture

EX: Air- comprised of N, O, CO2

Two parts:
a.
b.
Solvent: substance that a solute is dissolved in
Solutes: substance that is dissolved in a solvent
Biochemistry
Organic Compounds
 Compounds
that contain carbon
and occur naturally only in the
bodies and products of an
organism
Monomer vs. Polymer
 Monomer-
 Polymer-
1 sugar
2+ sugars; can
contain 100 or 1000 sugars
Macromolecule
 Another
name given to organic
compound because they are
very large compounds
Monomers

Carbs: sugar
Proteins: amino acids
Nucleic Acid: nucleotide

Skip question #6
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Examples of Carbohydrates

Anything that ends with –ose (maltose,
fructose, glucose)
Examples:

Lipids

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Proteins

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Fats, oils, waxes
Enzymes
Nucleic Acids

DNA, RNA
Classify:
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A. carb
B. carb
C. Lipids
D. Lipids
E. Lipids
F. Nucleic Acids
G. Nucleic Acids
H. Proteins
I-K. Carb

Disaccaharide:
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2 sugars (maltose)
Polypeptide:

2+ amino acids
connected by peptide
bonds
Polar vs. Nonpolar
 Water
is polar
 Polar molecule: a molecule
that has a partial positive and
partial negative charge
 Only polar substances will
dissolve in water; non polar
will not.
Enzymes
12/13. Proteins that are necessary for
life
14. It is a catalyst, which causes a
reaction to occur
15.pH, temperature affect
enzymes
16. Substance that is broken down
by enzyme
17. Area where substrate binds
The Cell: Make sure you know
the diagrams on plant and animal
cells
Cell Theory
 1.
All living things are
composed of one or more cells
 2. Cells are organisms’ basic
units of structure and function
 3. Cells come only from
existing cells
Prokaryotic vs. Eukaryotic Cells
 Prokaryotes:
Lack any internal
membrane bound structures
(most organelles) and nucleus
 Ex: bacteria
 Eukaryotes: have nucleus;
plants & animals
Cell Membrane
 Also
called Plasma Membrane
 Prokaryotes, Eukaryotes
 Plants & Animals
 Function: controls what enter
and leaves the cell
Cell Wall
 Found
in bacteria and plants
 Made of cellulose
 Function: gives cells its shape and
protection
Nucleus & Nuclear Envelope
 Only
in eukaryotes
 Function: Control center for
metabolism and reproduction
 Surrounded by a nuclear
envelope that is selectively
permeable
Nucleolus
 Eukaryotes
 Function:
makes ribosomes
Cytoplasm
 Eukaryotes
& Prokaryotes
 Jelly-like substance in between
cell membrane and nucleus
 Function: metabolism; holds
organelles in place
Endoplasmic Reticulum
 Eukaryotes
 Function:
highway of cell;
moves material from one end
to the next
Two Types:
 Rough
Endoplasmic Reticulum
(ER): ribosomes attached
 Smooth
ER: no ribosomes
Ribosomes
 Eukaryotes
 Function:
makes proteins
Golgi Complex
 Eukaryotes
 Flattened
stack of pancakes
 Modify and transport proteins
to parts of the cell
Lysosomes
 Eukaryotes
 Garbage
disposal; break down
food or bacteria
Mitochondria
 Eukaryotes
 Powerhouse
of cell
 Produces energy for the cell
Vacuoles
 Plants:
one large
 Animals: several small that
digest food or remove excess
water (similar to sponge)
Cilia & Flagella
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Involved in cell movement
Cilia: usually in animals
Flagella: usually one whip like structure
found in unicellar organisms
Microtubules & Microfilaments

Involved in cell movement and shape

Forms the cell’s cytoskeleton

Eukaryotes
Centrioles

Involved in cell division

Animals only
Plastids
 Plants
 Two
only
types:
1. Leucoplasts: starch storage
2. Chromoplasts: pigments for color
Choloroplast
 Type
of chromoplast
 Contains chlorophyll; site for
photosynthesis
 Plants only
Phospholipid Bilayer
Selectively Permeable
 Only
allows certain things to
enter or exit

EX: Cell Membrane
Organization
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Cell
Tissue
Organ (stomach, pancreas, liver)
Organ System (respiratory, circulatory)
Organism (human, dog, cat)
Tissue vs. Organ
 Tissue:
group of cells that
serve the same function
 Organ:
group of tissues that
serve the same function
Cell Transport
Active vs. Passive

Active


Energy Required
Moves from low
concentration to high
concentration

Passive

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No energy required
Moves from high
concentration to low
concentration
Diffusion
 Movement
of molecules from
an area of high concentration
to an area of lower
concentration
 Passive
Transport
Diffusion
Concentration Gradient
 Occurs
when there is a
difference between high and
low concentration
Equilibrium
 Same
amount is inside and
outside the cell
Osmosis
 Diffusion
of water across a
selectively permeable
membrane from region of
high water concentration to a
region of low water
concentration
 Passive
Plasmolysis vs. Cytolysis
Plasmolysis: shrinking of
cytoplasm (result of hypertonic
solution)
Cytolysis: cell explodes due to
hypotonic solution
Turgor Pressue
 Increase
of pressure in a plant
due to water entering the cell via
osmosis
 Plant cell will not explode
because of cell wall
 Greatest pressure in pure water
Facilitated Diffusion
 Special
transport proteins
transport substance into or
out of cell

Same as diffusion- movement from high to
low concentration
Endocytosis
 Transporting
material into cell by
vesicle
EX:
 Pinocytosis: small liquids are
taken into cell by vesicle
 Phagocytosis: solid particles
ingested into cell by vesicles
Exocytosis
 Transporting
material out of
cell by vesicle
Type of
Solution
Where is
there more
solute
Where is
there more
solvent
(water)
What
direction
does water
move
What
happens to
the cell
Hypotonic
Inside cell
Outside cell
Inside
Cytolysis
(explode)
Hypertonic
Outside cell
Inside cell
Outside
Plasmolysis
(shrink)
Isotonic
Equal
Equal
Constant
Nothin
Let’s Do Examples

Look at the examples on the board and
determine which way the water will move
and what will happen to the cell.