Transcript Biology Midterm Review

Advanced Biology Midterm Review
Holt Biology Chapters 1-6
Ch 1 Biology and You.
Ch 2 Chemistry of Life
Ch 3 Cell Structure
Ch 4 Cells and Their Environment
Ch 5 Photosynthesis and Cellular Respiration
Ch 6 Chromosomes and Cell Reproduction
Ch 1 Biology and You.
Key Terms
• Section 1 - Biology, Cell, Reproduction,
Metabolism, Homeostasis, Gene, Heredity,
Mutation, Evolution, Species, Natural selection,
Ecology,
• Section 2 – Genome, HIV, Cancer, Cystic
Fibrosis, Gene Therapy
• Section 3- Observation, hypothesis, prediction,
pH, experiment, Control Group, independent
variable, dependent variable, theory
Biology – Study of Life
All living things are made of cells.
Cell are the smallest unit capable of life.
Characteristics of All Living Things.
1. Cellular Organization
2. Reproduction
5. Heredity
3. Metabolism
6. Responsiveness
4. Homeostasis
7. Growth & Reproduction
Steps of the Scientific Method
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Collect Observation
Ask Questions
Formulate Hypothesis and Make Predictions
Experiment to confirm predictions - Collect and
Analyze Data
• Draw Conclusion and publish results.
Hypothesis – A statement that can be tested by
observation or experimentation.
Theory – A set of hypothesis that have been tested
and confirmed many times by many scientists.
• Experimental Group – The group in the
experiment that receives some type of treatment.
• Control Group – The group in the experiment that
receives no treatment.
• Independent variable- The factor that is changed
in the experiment
• Dependent variable – The variable that is
measured in the experiment.
Ch 2 Chemistry of Life
Key terms
• Section 1 – Atom, Element, Compound, Molecule,
Ion
• Section 2 – Cohesion, Adhesion, Solution, Acid,
Base
• Section 3 Carbohydrate, Monosaccharide, Lipid,
Protein, Amino Acid, Nucleic Acid, Nucleotide,
DNA, RNA, ATP
• Section 4 – Energy, Activation energy, Enzyme,
Substrate, Active site
Atom – Smallest unit of matter that cannot be broken
down.
Proton – Positive charge within nucleus
Neutron – no charge within nucleus
Electron – Negative charge – outside of nucleus.
• Element- pure substance made of only one kind of
atom.
• Compound – a substance made of atoms of two or
more elements
• Molecule – Two or more atoms covalently
bonded.
• Covalent Bond – Sharing of electrons.
• Hydrogen Bond – Electrostatic attraction between
water molecules.
• Ionic bond- An electrostatic attraction between
molecules who have gained or lost electrons.
Water Properties
Cohesion
Adhesion
Capillary action
Surface Tension
pH
H2O  H+ + OH-
Acid – form hydrogen ions when dissolved
in water. pH < 7
Base – Form hydroxide ions when dissolved
in water. pH > 7
Neutral – pH 7
Carbohydrates – organic compounds made of
carbon, hydrogen and oxygen in a 1:2:1 ratio.
Key source of energy found in fruits, vegetables
and grains.
Lipids include fats,
phospholipids, steroids
and waxes. Important in
the structure and
functioning of cell
membranes.
Proteins – Made of of amino
acids. Found in meat. Many
functions.
•Enzymes promote chemical
reactions.
•Collagen found in skin,
ligaments, tendons and bones.
•Structural proteins found in hair,
muscles and help blood clot.
•Antibody proteins help defend
against infection.
•Hemoglobin carries oxygen.
Nucleic Acids
DNA – Stores hereditary information
RNA – plays key role in the manufacture of proteins
ATP – Energy storing molecule.
Energy – ability to change matter.
Activation energy – the energy needed to start a reaction.
Enzymes lower activation energy.
Ch 3 Cell Structure
Key Terms
• Section 1 – Light microscope, electron
microscope, magnification, resolution, scanning
tunneling microscope.
• Section 2 – Cell theory, cell membrane,
cytoplasm, cytoskeleton, ribosome, prokaryotic,
cell wall, flagellum, eukaryote, nucleus, organelle,
cilium, phospholipids, lipid bilayer.
• Section 3 – Endoplasmic reticulum, vesicle, Golgi
apparatus, lysosome, mitochondrion, chloroplast,
central vacuole.
Ocular lens x objective lens =
total magnification
Magnification – making
image appear larger
Resolution – clarity of image
Cell Size – small cells function more efficiently
than large cells. Cells need large surface to
volume ratio.
Cell Theory
• All living things are made of cells.
• Cells are the basic units of structure and
function in organisms.
• All Cells come from existing cells.
Common Features of Cells
Cell membrane
Cytoplasm
DNA
Ribosomes
Cytoskeleton
No nucleus
Lack membrane bound
organelles.
Circular DNA
Cell wall surrounds
membrane
Nucleus containing
DNA.
Membrane bound
organelles.
Animal Cell
Plant Cell
Cell membranes are selectively permeable.
Ch 4 Cells and Their
Environment
Key Terms
• Section 1 – Passive transport, concentration
gradient, equilibrium, diffusion, osmosis,
hypertonic solution, hypotonic solution, isotonic
solution, ion channel, carrier protein, facilitated
diffusion.
• Section 2- Active transport, sodium-potassium
pump, endocytosis, exocytosis, receptor protein,
second messenger.
Passive Transport –does not require energy.
Diffusion – The
movement of a substance
from an area of high
concentration to an area
of lower concentration
until equilibrium is
reached.
Osmosis – The diffusion of water through a
selectively permeable membrane.
Diffusion through ion channels is passive
transport. It does not require energy.
Facilitated Diffusion is passive transport. It
requires carrier proteins but it does not require
energy. Why?
Active Transport
• The movement of a substance across the
cell membrane against its concentration
gradient.
• The energy needed for active transport is
supplied directly or indirectly by ATP.
Active Transport
An important carrier protein used to move substances
against the concentration gradient.
Active Transport
Endocytosis
Exocytosis
Ch 5 Photosynthesis and Cellular
Respiration
Key Terms
Section 1- Photosynthesis, autotroph, heterotroph, cellular
respiration.
Section 2 – Pigment, chlorophyll, carotenoid, thylakoid,
electron transport chain, NADPH, carbon dioxide fixation,
Calvin cycle.
Section 3- Aerobic, anaerobic, glycolysis, NADH, Krebs
cycle, FADH2, fermentation.
Flow of energy
• Energy flows from sunlight or inorganic
substances to autotrophs then to heterotrophs.
Photosynthesis
Sunlight contains a mixture of
wavelengths of visible light.
Chlorophylls absorb mostly violet, blue, and
red light, while carotenoids absorb mostly
blue and green light.
Pigment molecules are
embedded in thylakoid
membranes
The electron transport chain
converts light energy into
chemical energy.
Cellular Respiration
Cellular respiration
occurs in two stages.
Glycolysis is the first stage
of cellular respiration.
Glucose is broken down in
the cytoplasm.
Glycolysis is an anaerobic
process that breaks down one
six carbon glucose to two
three carbon pyruvate ions.
Glycolysis uses two ATP
molecules but produces four
for a net gain of two ATP
molecules.
When oxygen is present, pyruvate produced during
glycolysis enters a mitochondrion and Acetyl-CoA is
formed and carbon dioxide is released.
After the Krebs cycle, NADH and FADH2 contain energy that
was previously stored in glucose and pyruvate. These electrons
pass through the Electron Transport Chain in the inner
membranes of the mitochondria.
Most ATP is produced during aerobic respiration.
When oxygen is not present, fermentation follows glycolysis
regenerating NAD+ for glycolysis to continue.
Ch 6 Chromosomes and Cell
Reproduction
Key Terms
Section 1 – Gamete, binary fission, gene,
chromosome, chromatid, centromere, homologous
chromosome, diploid, haploid, zygote, autosome,
sex chromosome, karyotype.
Section 2 – Cell cycle, interphase, mitosis,
cytokinesis, cancer.
Section 3 - Spindle
Prokaryotic Cells
• Cell division is simple.
• A single cell doubles
in size and then
separates into two
daughter cells
• Binary fission
Eukaryotic Cell
• Cell division more
complex.
• Process of cell
division called
mitosis.
Chromosomes contain genetic information.
After replication become visible by
condensing.
• Chromatids - one of the
two strands of a
chromosome that become
visible during mitosis.
• Centromere - the region of
the chromosome that holds
the two sister chromatids
together during mitosis
Chromatin - DNA and associated proteins
observed when the nucleus in not dividing.
Phases of the cell cycle.
• G 1 - Most of the cell’s
growth takes place.
• S phase - chromosome
replication takes place.
• G 2 - preparation for cell
division.
• M phase (mitosis) - Cell
division takes place.
Cancer cells lose the normal ability to
regulate the cell cycle.
The Cell Cycle -Interphase
• G 1, S, G 2, period
between cell divisions.
• The long strands of DNA
and protein that make up
chromosomes unfold and
are difficult to see.
• Chromosomes active
directing cell growth &
development.
Mitosis - Prophase
• Longest phase- 50% of
mitosis.
• Chromosomes appear as
a result of condensing
and coiling of chromatin.
• Chromosomes consist of
2 identical strands
attached at the
centromere.
Prophase
• In animal cells two
centrioles (b.) separate
and move to opposite
sides of the nucleus
• Spindle fibers (c.) network of microtubules
begin to form.
• Nucleus begins to
disappear.
Metaphase
• Shortest phase of
mitosis - lasts only a
few minutes.
• Chromosomes
complete attachment
to spindle fibers
• Chromosomes line up
across the middle of
cell
Anaphase
• Centromeres split,
allowing sister
chromatids to separate.
• Chromosomes move
to opposite poles.
• Anaphase is complete
when chromosomes
have stopped moving.
Telophase
• Microtubules of the
spindle begin to break
apart
• Chromosomes uncoil
into chromatin
• Nuclear membrane
forms
Cytokinesis
• The division of
the cytoplasm
into 2 individual
cells
• Animal cells pinching
• Plant cells - plate
forms.