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1 Unit 1: Biomolecules I. Terms You Should Know lipid fatty acid & glycerol monomer biomolecule protein amino acid nucleic acid nucleotide DNA/RNA enzymes lock and key model catalyst carbohydrate monosaccharide glucose Polypeptide Peptide bonds II. Content A. Function of biomolecules 1. Carbohydrates are used for fast energy. 2. Lipids are used for long term energy storage. 3. Proteins are used for enzymatic functions, structure, transport, and growth/repair. 4. Nucleic Acids are used for genetic information. B. Structure of biomolecules 1. Carbohydrates are made up of monosaccharides. 2. Lipids are made up of long fatty acids chains and glycerol. 3. Proteins are made of amino acids, connected by peptide bonds. Proteins are also known as polypeptides. 4. Nucleic acids are made up of nucleotides, connected by hydrogen bonds. C. Enzymes 1. Enzymes are used to make reactions happen faster. They don't get used up in the reaction. 2. The substrate fits perfectly into the enzyme, like a key fits into a lock. That is why enzymes are substrate-specific. 3. If enzymes are heated up or put in acid, the shape/structure of the enzyme is changed and they cannot do their job. 1

2 Unit II: Cells I. Terms to know Prokaryote Eukaryote Mitochondria Chloroplast Cell membrane Vacuole Ribosome Cell cycle Mitosis Interphase Prophase Metaphase Anaphase Telophase Cytokinesis Specialization/ Differentiation HIV Cancer Virus Capsid Protein receptors Influenza II. Content A. Prokaryote vs. Eukaryote 1. Prokaryotes have no nucleus, and no membrane-bound organelles. They are 100% bacteria. 2. Eukaryotes have nuclei and membrane-bound organelles. They include plants, protists, animals, and fungi. B. Cell Structure (Organelles) 1. Contractile vacuole is responsible for moving water in/out of a cell. 2. Chloroplasts are in plants and make glucose (a carb). 3. Mitochondria are used to make ATP (energy) 4. Cell (plasma) membrane is the outer phospholipid bilayer of the cell that acts as a barrier. 5. Golgi body acts as a UPS system, and packages proteins. 6. Lysosomes break down molecules. 7. Vesicles are sacs that hold fluid and molecules. 8. Ribosomes make proteins. 9. Rough endoplasmic reticulum (RER) is involved in protein synthesis. 10. Smooth ER is involved in fat synthesis. 11. Cell walls are made of cellulose (a sugar), and are only found in plants. C. Cellular Transport 1. Selective permeability means that only certain molecules can go in/out of the cell membrane. 2. Fluid mosaic model shows how the proteins embedded in the cell membrane can move around. 3. The cell membrane is called a phospholipid bilayer because the outside and inside is hydrophilic (likes water), but the inside of the membrane is hydrophobic (does not like water). 4. Passive transport requires no energy. 5. Osmosis is the passive transport of water. 6. Facilitated diffusion is the passive transport of molecules using proteins in the membrane. 7. Active transport requires energy (ATP) to move molecules against the concentration gradient. 2

3 8. If a cell is placed in a hypertonic solution, there is a higher concentration of solutes outside than inside the cell, so the cell will give water to the outside and shrink. 9. If a cell is placed in a hypotonic solution, there is a higher concentration of solutes inside than outside the cell, so the cell will take on water and swell. D. Cell Cycle 1. Purpose of the cell cycle is to make 2 cells that have the exact same DNA. In humans, the parent cell has 46 chromosomes, and so do the two daughter cells. 2. Interphase is made of 3 steps: G1 (growth), S (DNA replication), G2 (preparation to divide). 3. Mitosis is made of 4 steps: Prophase, Metaphase, Anaphase, and Telophase. 4. Prophase: Chromosomes condense and the nucleus breaks down. 5. Metaphase: Chromosomes align in the equator (Middle). 6. Anaphase: Chromosomes are pulled Away to opposite poles. 7. Telophase: Two nuclei form around the chromosomes. 8. Cytokinesis: Cytoplasm is Cut into Mutations in DNA cause a disruption of the cell cycle which could lead to cancer E. Viruses 1. Viruses are made up of: capsid (the protective outer layer), and nucleic acid (genetic information to make more viruses). 2. Lytic cycle: Virus binds to proteins on host cell's membrane, injects genetic information, makes copies of itself, lyses (explodes the host cell) 3. Lysogenic cycle: Virus binds to proteins on host cell's membrane, injects genetic information, waits for host to replicate and the right time to attack 4. Lysogenic cycle takes longer, lytic cycle is shorter 5. Viruses cannot reproduce without a host cell. 6. Viruses are not alive. 3

4 Unit III: Genetics I. Terms you should know Nucleotide Nitrogen base Thymine Adenine Guanine Cytosine Uracil Phosphate group Deoxyribose sugar Ribose sugar Hydrogen bond Genetic code Transcription Translation Ribosome trna mrna Protein synthesis Mutation Insertion Deletion Substitution Frameshift Gene regulation Gene expression Trait Genotype Phenotype Heterozygous Allele Homozygous dominant Homozygous recessive Meiosis DNA fingerprint Genetic modification Karyotype Crossing over Codon Gametes II. Content A. DNA structure 1. DNA is in a double helix, also known as a twisted ladder. 2. DNA is made up of nucleotides. 3. Each nucleotide has a phosphate group, a sugar, and a nitrogenous base (Adenine, Thymine, Cytosine, or Guanine) 4. Nitrogen bases are in the middle of the double helix. 5. Sugar and phosphate make up the backbone (outside). 6. Nitrogenous bases are connected by hydrogen bonds. 7. All living organisms have DNA made of nucleotides. 8. Every cell in an organism has the same DNA. However, cells can be differentiated - changed to serve different functions (hair cell, skin cell, muscle cell, etc). 9. Gene regulation is when you turn gene expression on or off. If the gene is turned on, the protein it codes for will be made. If it is off, no protein will be made. 10. Gene expression can be affected by DNA, RNA, and environmental factors. It is regulated. 11. While all genes are coded for by the DNA nucleotides, the order of the nucleotide bases determines the trait that is expressed. B. Making proteins! 1. A gene from the DNA in the nucleus is transcribed (copied) into mrna in a process called transcription a) mrna stands for messenger RNA. b) mrna does not have thymine as a base. Instead, it has uracil (U). 2. The mrna then goes to find a ribosome in the cytoplasm. 3. The ribosome reads the mrna 3 bases at a time, called a codon. 4. The trna, transfer RNA, brings the amino acids that are coded for by the codon to the ribosome. 4

5 5. The ribosome puts the amino acids together to form a polypeptide/protein in a process called translation. C. Mutations 1. Mutations are changes in the DNA bases (The ATCG) 2. A point mutation is a change in one DNA base. a) If the DNA base is replaced with another, this is a substitution. b) If the DNA base is taken out, this is a deletion. c) If a DNA base is added, this is an insertion. 3. Insertions and deletions will result in a frameshift. That means that all of the amino acids after the change can be different. 4. If the DNA is changed, the amino acid sequence that is created could be different The protein that is made has the possibility to either express a new trait, result in disease, or no change. D. Inheritance (Passing on your DNA) 1. Inheritance a) Meiosis - process through which gametes (Egg/sperm) are made b) Meiosis produces 4 unique gametes. c) Genetic recombination occurs because chromosomes assort independently and crossing-over occurs. This results in genetic variation. (1) Crossing over is the swapping of DNA of homologous chromosomes (2) Independent assortment is the random separation of homologous chromosomes d) To create a zygote, an egg must be fertilized by a sperm e) Each gamete is haploid meaning it has half the number of chromosomes of a regular cell. (1) In humans, gametes have 23 chromosomes. f) For every gene, you get one copy from mom and one copy from dad. They reside on homologous chromosomes. 2. Crosses a) Alleles are different versions of a gene. b) There is usually a dominant allele, written as a capital letter, and a recessive allele, written as a lowercase letter. c) If an organism has two dominant alleles (RR) or two recessive alleles (rr), they are homozygous for that trait. d) If an organism has one dominant allele and one recessive allele (Rr) they are heterozygous for that trait. (1) homozygous dominant - RR (2) heterozygous - Rr (3) homozygous recessive - rr e) In simple Mendelian inheritance, if an organism has even one dominant allele, they will express that phenotype. f) Genotype - the alleles (letters) you have g) Phenotype - the trait you express (what you look like) 3. Non-Mendelian Inheritance a) co-dominance - both dominant alleles show (cooperate) (1) Ex: Blood (I A, I B, i) (a) Dominant: having antigens, Recessive: no antigens 5

6 (b) I A I B - Type AB (has both A and B antigens) (c) I A i - Type A (only A antigens) (d) I B i - Type B (only B antigens) (e) ii - Type O (no antigens) b) incomplete dominance - the alleles mix (incomplete) (1) Ex: Snapdragons (R - red, r - white) (a) RR - red flowers (b) Rr - red + white = pink flowers (c) rr - white flowers E. Cool things about DNA 1. Genetic Modifications a) The gene of interest is inserted into a bacterium (via a plasmid) b) The purpose is to produce the product (protein) of the gene en masse 2. Karyotype a) Shows the chromosomes of the person b) Can be used to look for trisomies (extra chromosome) or absence of a chromosome c) The last pair of chromosomes are the sex chromosomes (1) XX - female (2) XY - male 3. DNA Fingerprinting a) DNA is extracted from a sample, cut by enzymes, and sorted by size b) Banding patterns are used to compare two samples (1) We can tell how closely related organisms are (2) We can use it to determine parents (bands must come from either mom or dad) (3) We can use it to solve crimes! (Compare suspect's DNA fingerprint to the criminals') 6