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You Asked for it..

• Biology REVIEW

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biomolecules
Building Block Uses Examples Test
Carbohydrate Simple sugars Ready source of energy Glucose Glycogen Cellulose Starch STARCH turns purple in iodine SUGARS react with Benedicts Solution
Protein Amino acids Transport Speed up reactions Immunity Cell communication Enzymes (-ase) Hemoglobin Antibodies Protein hormones (insulin) Reacts with Biuret Solution
Lipid Fatty Acids Back up energy source In membrane Fats, oils Leaves oily spot on brown paper bag
Nucleic Acid Nucleotide Store and transmit genetic info DNA, RNA DNA stains (methylene blue)
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CELLS

• EUKARYOTIC

• PROKARYOTIC

• Eukaryotic cells have their DNA surrounded by a
  membrane.  (They have a nucleus). 
• Two examples shown are plant cells and animal
  cells, but fungi and protists are also eukaryotic
• Notice, plants have chloroplasts (for
  photosynthesis) and cell walls made of cellulose.
  Animal cells don't have these parts.  Also, plant
  cells have a larger vacuole for storage. 
• Both plants and animals have mitochondria to make
  ATP.
• All eukaryotic cells have ribosomes to make
  protein
• These cells are more complex than prokaryotic
  cells.

• Prokaryotic cells have DNA and ribosomes, but
  they have no internal membranes! (They don't have
  a nucleus)
• They have ribosomes to make proteins
• These are the simplest cells
• Examples are bacteria, like those that cause
  strep throat.

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CELL MEMBRANE

• The plasma membrane surrounds EVERY cell.
• It is made of lipid and protein
• It controls what goes in and out of a cell.
• Associated with HOMEOSTASIS

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CELL TRANSPORT
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Enzymes

• are specific for reactions
• speed up reactions
• bind to substrate at active site
• are reusable
• are not changed in the reaction
• are made of PROTEIN

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Photosynthesis and Respiration

• Converts sunlight to chemical energy

• Converts energy in food (glucose) to ATP

• Cellular Respiration
• Takes place in mitochondrion
• Releases the energy stored in glucose
• AKA aerobic respiration (NEEDS oxygen)

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AEROBIC vs AnAEROBIC RESPIRATION

• AEROBIC RESPIRATION

• ANAEROBIC RESPIRATION

• Requires oxygen
• Makes A LOT of ATP
• Produces carbon dioxide and water
• Happens in mitochondrion

• Does not use oxygen
• Makes only 2 ATP
• Small amount of ATP
• Also called fermentation
• YEASTS make ethyl alcohol
• BACTERIA and MUSCLE CELLS (w/o O2) make LACTIC
  ACID
• Happens in cytoplasm (cytosol)

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Atp cYCLE
CLICK THE ICON FOR SOUND
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Asexual vs Sexual Reproduction

• Sexual Reproduction

• Asexual Reproduction

• Adds genetic variation
• Involves meiosis and fertilization
• TWO parents involved
• Diploid and haploid cells

• Creates identical copies (clones)
• Only involves MITOSIS
• ONE parent involved
• Common in bacteria and unicellular protists

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Mitosis and Meiosis

• Meiosis

• mitosis

• One division
• 2n ? 2n
• (same number of chromosomes)
• Results in 2 genetically identical cells

• Two divisions
• 2n ? n
• Half the number of chromosomes
• Results in 4 DIFFERENT haploid cells
• Forms gametes (egg and sperm)

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DNA

• DNA is a polymer of nucleotides.
• A nucleotide is made up of three parts a sugar,
  a phosphate and one of four bases
• In DNA, the bases are A, T, C, and G
• DNAs shape is a double helix
• The two strands are held together by HYDROGEN
  bonds
• A binds to T
• C binds with G

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DNA Replication

• Process of DNA copying itself
• Steps
• DNA Unzips (Hydrogen bonds break)
• Each side acts as a template
• New DNA nucleotides are added according to
  base-pairing rules
• Two new molecules of DNA result each with one
  old and one new strand.
• Happens in INTERPHASE (before mitosis or meiosis)

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Protein Synthesis

• Remember, genes are made of DNA and are in the
  nucleus
• Genes (DNA) contain the instruction for making  a
  protein
• In transcription, DNA is used to make mRNA in the
  nucleus
• mRNA then leaves the nucleus and goes to the
  ribosome
• In translation, tRNA then brings amino acids in
  the proper order to make the protein on the
  ribosome.

DNA ? mRNA ? protein
Made of amino acids
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PROTEIN SYNTHESIS
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Can you IDENTIFY the parts?

1. DNA
2. mRNA
3. Nucleus
4. Cytoplasm
5. Ribosome
6. Codon
7. Anticodon
8. tRNA
9. Amino acid
10. Protein (polypeptide)

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READING THE CODON CHART

• Be sure to use mRNA
• You wont have to memorize this!
• What amino acid is coded for by the DNA
• ATA GAG

First convert DNA to mRNA ATA GAG UAU CUC UAU
tyr CUC Leu
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Genetics

• We have two genes for each trait this is our
  GENOTYPE
• One gene came from mom, one from dad
• If the genes are alike, the individual is
  homozygous (RR, rr)
• If the genes are different , they are
  heterozygous (Rr)
• Some genes are dominant and others are recessive
• We only show a recessive trait if we have no
  dominant gene
• RR and Rr would look dominant
• rr would look recessive

• This diagram shows the cross between 2
  heterozygous purple flowers
• Cross is Bb x Bb
• Notice that 75 are purple and 25 white

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Sex Linkage

• Females are XX
• Males are XY
• Sex-linked traits are on X chromosome
• Trait is more common in MALES
• Examples are colorblindness and hemophilia (blood
  fails to clot)

• Males give X chromosomes to their daughters and
  Ys to their sons
• Moms give Xs to both daughters and sons

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CODOMINANCE BLOOD TYPE

• Four blood types
• A, B, AB, O
• Three different alleles A, B or neither

• A AA or AO
• B BB or BO
• AB AB
• O OO

Agglutinogen protein
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PEDIGREES

• Tracing traits through generations
• Males are squares
• Females are circles
• Horizontal line means married
• Vertical line means children
• Filled in circle means the individual HAS the
  condition
• Can you identify the genotypes of individuals 4,
  7, 12?

4 Ee (parent 2 had to give an e) 7 Ee (child
is ee, so they had to have one e) 12 ee
(affected with recessive condition)
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KARYOTYPE
XY male

• A chart showing arrangement of chromosomes

• In humans, 22 pair of autosomes
• 1 pair of sex chromosomes
• XX female
• XY male
• Extra chromosomes a result of non-disjunction
• Chromosome pairs fail to separate in meiosis
• One example is DOWN SYNDROME (extra 21)
• Another example is KLINEFELTERS (XXY)

3 21s Down Syndrome
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GENETIC TECHNOLOGY

• DNA FINGERPRINTING

• TRANSGENIC organisms

• Use gel electrophoresis to compare DNA fragments
• IF DNA matches, its from the same individual

• Organisms that have 2 different kinds of DNA
• Gene cloning
• Uses bacteria to make human proteins like insulin

Evidence points to suspect 2
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EVOLUTION change over time

• EVIDENCE

• Natural Selection

• Fossil evidence
• Fossils found in sedimentary rock
• Lower level fossils are older and more PRIMITIVE
• We can compare fossils to modern organisms
• Similar structure suggests common ancestor
• Biochemical evidence
• DNA and protein similarities suggest common
  ancestor

• Credited to Charles Darwin
• Organisms in populations have variations that can
  be passed from generation to generation
• More organisms born that environment can support
• Organisms compete for resources
• Those organisms with favorable variations have
  more babies and the population evolves

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ECOLOGY AND ECOSYSTEMS
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Food CHAINS

• Original source of energy for most chains is the
  sun
• 1st trophic level is producer
• 2nd trophic level is primary consumer
• 2rd trophic level is secondary consumer
• Decomposer not shown on chain, but they recycle
  nutrients

Energy is lost as you mover up the food chain
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SYMBIOSIS
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Predation

• Predator EATS Prey
• The populations cycle
• Predator has lower curve
• There cant be more predators than prey

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Population GROWTH

• EXPONENTIAL GROWTH

• Logistic growth

• J-curve
• Occurs when unlimited resources are available

• S-curve
• Occurs because resources are limited
• Carrying capacity reached

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HUMAN POPULATION GROWTH

• Overpopulation of humans leads to
• Destruction of habitats (pollution and/or
  destroying)
• Loss of biodiversity
• Introduced species
• Outcompete nativespecies

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Carbon CYCLE

• Cycling of carbon and oxygen
• Three main processes
• Photosynthesis plants use carbon dioxide
  produce oxygen
• Respiration uses oxygen, produces carbon
  dioxide (both plants and animals)
• Combustion burning releases more carbon
  dioxide

• Greenhouse Effect
• Carbon dioxide traps heat in the atmosphere,
  making life possible
• Increased carbon dioxide can make temperatures
  rise more
• Human activities can lead to GLOBAL WARMING

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BE A GOOD STEWARD