Midterm Review

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Midterm Review
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Chapter 1

• Biology and You

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7 Characteristics of Living Things

• Cellular organization
• Reproduction
• Metabolism
• Homeostasis
• Heredity
• Responsiveness
• Growth development.

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Levels of Organization in Living Things

• Organelles
• Cells
• Tissues
• Organs
• Organ system
• Organism

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Science vs. Biology

• Science
• Process of thinking learning about the world
• Biology
• Study of life

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Steps of the Scientific Method

• State the problem based on observations.
• Research the problem.
• Form a hypothesis.
• Test the hypothesis (experiment).
• Collect and analyze the data.
• Form a conclusion.
• Report the results.

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Control vs. Variable

• Control
• The standard of comparison for the experimental
  group
• Receives no experimental treatment
• Variable
• The one factor that differs among the test
  groups.
• Part of the experimental group

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Independent vs. Dependent Variable

• Independent variable factor changed by the
  experimenter (the factor tested) - a good
  experiment tests one variable.
• Dependent variable factor that depends on the
  value of the independent variable (a result
  measured).

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Independent vs. Dependent Variable
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Observations

• Qualitative
• Observations that deal with the characteristics
  of the object such as hardness, texture, beauty,
  etc.
• Quantitative
• Observations that deal with numbers such as the
  mass, how many, how long, etc.

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Theory vs. Hypothesis vs. Prediction

• Theory
• A set of related hypotheses that have been tested
  and confirmed many times by many scientists.
• Unites and explains a broad range of
  observations.
• Hypothesis
• An educated guess based on observations
  research that can be tested.
• Prediction
• Expected outcome of a test assuming the
  hypothesis is correct.

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Base Units of the Metric System

• Meter
• Measures length
• Liter
• Measures volume
• Gram
• Measures mass
• Celsius
• Measures temperature

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Chapter 2

• Chemistry of Life

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Atom and Its Parts

• An atom is the smallest unit of an element that
  maintains the properties of that element.
• Nucleus contains
• Proton ()
• Neutron (Neutral)
• Electron cloud
• Electron ()

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Covalent vs. Ionic Bonds

• Covalent Bond
• Bond formed when atoms share pairs of electrons.
• Ionic Bond
• Bond formed by the attraction between oppositely
  charged ions.

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Covalent vs. Ionic Bonds
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Molecules and Polar Molecules

• Molecule
• A group of atoms held together by covalent bonds.
  
• Polar Molecule
• Shares its electrons unequally and therefore has
  partially positive and negative ends, or poles.
• Water is a polar molecule.

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Molecules and Polar Molecules
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Solvents

• Solvent
• A substance, usually a liquid, capable of
  dissolving another substance.
• Universal Solvent
• Water.

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pH Scale and Acids Bases

• pH Scale ranges from 0 - 14
• Acid
• A compound that forms hydrogen ions (H) in
  water.
• Its pH is 0 to less than 7. (0 to lt 7)
• Base
• A compound that forms hydroxide ions (OH-) in
  water.
• Its pH is greater than 7 to 14. (gt7 to 14)
• Neutral
• Substances that have a pH of 7.

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Organic Macromolecules

• Organic macromolecules
• Contain carbon atoms that are covalently bonded
  to other elements typically hydrogen, oxygen
  and other carbon atoms.
• 4 principal classes of organic compounds found in
  living things are
• Carbohydrates
• Lipids
• Proteins
• Nucleic acids

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Organic Macromolecules

• Carbohydrates organic compounds made of carbon,
  hydrogen and oxygen in a 121 ratio.
• Monomers are monosaccharides.
• Ex Glucose and fructose
• Polymers are polysaccharides.
• Ex Starches, potatoes, paper, crab shells
• Functions
• Stores energy.
• Makes up cell walls in plants and fungi.
• Makes up exoskeleton in some animals.

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Organic Macromolecules

• Lipids are nonpolar molecules that are insoluble
  in water include fats, phospholipids, steroids
  and waxes.
• Monomers are glycerol fatty acids
• Polymer examples
• Butter oil
• All membranes
• Cholesterol and Steroids
• Functions
• Stores energy
• Makes up cell membranes
• Acts as chemical messengers

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Organic Macromolecules

• Proteins
• Monomers are amino acids
• Polymer examples
• Hemoglobin and antibodies
• Muscle, hair and nails
• Functions
• Hemoglobin carries oxygen and antibodies help
  defend against infection.
• Make up tissues that support body structures and
  provide movement
• Speed up chemical reactions (enzymes)

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Organic Macromolecules

• Nucleic acids
• Monomers are nucleotides
• Polymer examples
• DNA
• RNA
• Functions
• Controls cellular activities
• Stores hereditary information
• Plays key role in the manufacture of proteins

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Catalyst vs. Enzyme

• Catalyst
• Speeds up chemical reactions by lowering the
  activation energy.
• Enzyme
• Specialized protein that acts as an organic
  catalyst.

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Test Indicators Positive Results

• Benedicts solution
• Tests for simple sugars blue color changes to
  red, orange, yellow, green.
• Lugols iodine
• Tests for starch reddishorange iodine turns
  blue-black or black.
• Biuret solution
• Tests for protein blue turns purple.
• BTB (Bromthymol blue)
• Tests for CO2 blue turns green, or yellow.

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Chapter 3

• Cell Structure

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Microscopes

• Review the different types of microscopes and
  their uses.
• Review the parts and functions of a microscope
• To determine the total magnification of a
  microscope multiply the eyepiece (ocular lens)
  times the objective lens.

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Cell Theory

• All living things are made of one or more cells.
• Cells are the basic unit of structure and
  function in organisms.
• All cells arise from existing cells.

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Prokaryote vs. Eukaryote

• Prokaryote
• No nucleus
• No membrane bound organelles
• Circular DNA
• Relatively small
• Reproduce quickly (20 min.)
• Examples Bacteria

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Prokaryote vs. Eukaryote

• Eukaryote
• Nucleus
• Many membrane bound organelles
• Linear DNA
• Relatively large
• Reproduce slowly (24 hours)
• Examples Plants, animals, fungi protists

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Cell Parts Functions

• Cell membrane
• Controls what enters leaves a cell separates
  protects the cell from the environment.
  
• Nucleus
• Contains the DNA in eukaryotic cells controls
  cellular activities.
• Vacuole
• Membrane bound sac that stores water, may also
  contain ions, nutrients waste.

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Cell Parts Functions

• Chloroplast
• Organelle that uses light energy to make
  carbohydrates from CO2 H2O.
• Cytoplasm
• Region of the cell within the membrane that
  includes the fluid, the cytoskeleton and all of
  the organelles except the nucleus.
• DNA
• Material that contains the information that
  determines hereditary characteristics.

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Cell Parts Functions

• Ribosomes
• Organelle composed of RNA protein site of
  protein synthesis.
• Mitochondrion
• Cell organelle surrounded by 2 membranes is the
  site of cellular respiration, which produces ATP.
  
• Cell Wall
• Rigid structure that surrounds the cell membrane
  provides support to the cell.

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Chapter 4

• Cells and Their Environment

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Diffusion vs. Osmosis

• Diffusion
• The movement of particles from regions of higher
  concentration to regions of lower concentration.
• Ex perfume spreading across a room.
• Osmosis
• The diffusion of water from an area of high
  concentration to an area of low concentration
  across a membrane.
• Ex Getting thirstier when you drink salt water.

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Passive vs. Active Transport

• Passive Transport
• Does not require energy.
• Movement down the concentration gradient.
• Examples
• Diffusion
• Osmosis
• Facilitated diffusion

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Passive vs. Active Transport

• Active Transport
• Requires energy.
• Movement against the concentration gradient.
• Examples
• Sodium-potassium pump
• Endocytosis
• Phagocytosis
• Pinocytosis
• Exocytosis

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Chapter 5

• Photosynthesis
• and
• Cellular Respiration

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ATP

• The energy currency of the cell.
• An organic molecule that acts as the main energy
  source for cell processes
• Composed of a nitrogen base, a sugar 3
  phosphate groups.
• The energy is stored in the phosphate bonds.
• Powers metabolism.

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Photosynthesis

• Process by which plants, algae some bacteria
  use sunlight, CO2 H2O to produce carbohydrates
  O2.
• Takes place in the chloroplast
• Main pigment is chlorophyll.
• Reactants are CO2 and H2O
• End products are glucose O2

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Photosynthesis

• Stage 1
• Consists of the absorption of light energy which
  excites the electrons in chlorophyll.
• The electrons enter the ETC (electron transport
  chain).
• Water is split to produce O2, H, and the
  electrons to replace those lost by the
  chlorophyll molecules.

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Photosynthesis

• Stage 2
• The conversion of light energy into chemical
  energy that is temporarily stored in ATP and
  NADPH.
• The energy from ATP and NADPH will be used to
  power the third stage.

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Photosynthesis

• Stage 3
• CO2 fixation occurs
• Inorganic CO2 is fixed into organic compounds
  (sugars).

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Cellular Respiration

• Process by which cells produce energy from
  carbohydrates O2 combines w/ glucose to form H2O
  CO2.
• Takes place in the mitochondrion.
• Reactants are glucose and oxygen.
• Products are carbon dioxide water.

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Aerobic Respiration vs. Anaerobic Respiration

• Aerobic Respiration
• Requires oxygen.
• Produces much more ATP (38 net ATP)
• Anaerobic Respiration
• Does not require oxygen.
• Regenerates NAD so that gylcolysis can continue.
  
• (2 net ATP from glycolysis)

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Aerobic Respiration

• Stage 1 Glycolysis takes place in the
  cytoplasm.
• Does not require oxygen.
• Glucose is broken down to 2 pyruvate molecules
• Produces 2 net ATP and 2 NADH
• Stage 2 Bridge reaction carries pyruvates into
  the mitochondrion.
• 2 CO2 and 2 NADH are produced

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Aerobic Respiration

• Stage 3 Krebs Cycle occurs in the matrix of the
  mitochondrion
• In the presence of oxygen.
• In two turns of the Krebs Cycle
• 4 CO2 are produced
• 6 NADH are produced
• 2 ATP are produced
• 2 FADH2 are produced.

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Aerobic Respiration

• Stage 4 Electron Transport Chain occurs in the
  inner membrane of the mitochondrion
• In the presence of oxygen.
• 34 net ATP produced
• 2NADH from glycolysis 6ATP
• 2 NADH from bridge reaction 6 ATP
• 6 NADH from Krebs cycle 18 ATP
• 2 FADH2 from Krebs cycle 4ATP

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Anaerobic Respiration or Fermentation

• Alcoholic Fermentation
• Occurs in the absence of oxygen
• Occurs in yeast and some bacteria
• Produces
• Ethyl alcohol
• Carbon dioxide
• Regenerates NAD so glycolysis can continue

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Anaerobic Respiration or Fermentation

• Lactic Acid Fermentation
• Occurs in the absence of oxygen
• Occurs in the muscle tissue of animals in
  lactic acid bacteria
• Produces
• Lactic acid
• Regenerates NAD so glycolysis can continue

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Chapter 6

• Chromosomes
• and
• Cell Reproduction

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Chromosomes

• Chromosomes are DNA its associated proteins.
• We have 46 chromosomes or 23 pairs of
  chromosomes.
• In a prokaryotic cell, it is the main ring of
  DNA.

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Autosomes vs. Sex Chromosomes

• Autosomes are any chromosomes that are not
  directly involved in determining the sex of an
  individual.
• We have 22 pairs.
• Sex chromosomes contain genes that will determine
  the sex of the individual.
• We have one pair.
• Females are XX.
• Males are XY.

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Gametes

• Gametes are an organisms reproductive cells.
• Females gametes are eggs or ova.
• Males gametes are sperm.

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Haploid vs. Diploid

• Haploid refers to a cell (gamete) that contains
  only 1 set of chromosomes.
• It is represented by n.
• Diploid refers to a somatic or body cell that
  contains 2 sets of chromosomes.
• It is represented by 2n.

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Karyotype

• A karyotype is a photo of the chromosomes in a
  dividing cell that shows the chromosomes arranged
  by size.
• A trisomy at 21 indicates the individual has Down
  syndrome.

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5 Stages of the Cell Cycle
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5 Stages of the Cell Cycle

• The first 3 stages are collectively called
  interphase. (90 of a cells life is spent here.)
• First growth (G1) phase
• Cell grows rapidly carries out routine
  functions. (Major portion of a cells life is
  spent here.)

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5 Stages of the Cell Cycle

• Synthesis (S) phase
• Cells DNA is copied.
• Each chromosome consists of 2 chromatids attached
  at the centromere.
• Second growth (G2) phase
• Preparations are made for the nucleus to divide.
• Microtubules are rearranged.
• Organelles are manufactured or reproduced.

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5 Stages of the Cell Cycle

• Mitosis
• The nucleus of a cell divides into 2 nuclei each
  with the same and kinds of chromosomes as the
  original cell.
• Cytokinesis
• The cytoplasm divides and 2 new cells are formed.

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3 Checkpoints

• A checkpoint is an inspection point at which
  feedback signals from the cell can trigger the
  next phase of the cell cycle or delay it.
• Cell Growth (G1) checkpoint at the end of the G1
  phase
• Makes the decision of whether or not a cell will
  divide.

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3 Checkpoints

• DNA synthesis (G2) checkpoint at the end of the
  G2 phase
• DNA replication is checked by DNA repair enzymes.
• Mitosis checkpoint at the end of mitosis
• Triggers the exit from mitosis

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4 Phases of Mitosis

• Prophase
• Chromosomes become visible.
• Nuclear envelope dissolves.
• The spindle forms.
• In animal cells, the centrioles move to opposite
  poles and the spindle forms between them.

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4 Phases of Mitosis

• Metaphase
• Chromosomes move to the center of the cell line
  up along the equator.
• Spindle fibers link the chromatids of each
  chromosome to opposite poles.

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4 Phases of Mitosis

• Anaphase
• Centromeres divide.
• The 2 chromatids (now called chromosomes) move
  toward opposite poles as the spindle fibers
  attached to them shorten.

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4 Phases of Mitosis

• Telophase
• A nuclear envelope forms around the chromosomes
  at each pole.
• The chromosomes uncoil and return to chromatin
  form.
• The spindle dissolves.
• Cytokinesis begins.

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Cytokinesis

• Division of the cytoplasm of a cell
• Follows the division of the cells nucleus by
  mitosis or meiosis
• Cytokinesis in animal cells occurs when a belt of
  protein threads pinches the cell membrane in
  half.
• Cytokinesis in plant cells occurs when vesicles
  from the Golgi apparatus fuse to form a cell
  plate.

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Cytokinesis

• Cytokinesis in Cytokinesis in
• animal cells plant
  cells

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Energy pathway from sun to fox
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Enzymes

• Organic catalyst
• Speeds up chemical reactions by lowering the
  activation energy

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Photosynthesis vs. Cellular Respiration

• Photosynthesis
• Cellular Respiration

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Review the following labs

• Compound Light Microscope Lab
• Cell Structure Lab (Lab 9)
• Diffusion Demo Lab
• Osmosis worksheet
• Fermentation Lab (Inv. 17)