Mid-Year Biology Honors Study Guide PDF

Mid-Year Biology Honors Study Guide Topic 1 Introduction to Science 1. What is Science? Science is the way of learning the natural world through observation, experimentation, and analysis to discover how the world works. 2. List and describe every step of the Scientific Method 1.​ Make observ...

Mid-Year Biology Honors Study Guide Topic 1 Introduction to Science 1. What is Science? Science is the way of learning the natural world through observation, experimentation, and analysis to discover how the world works. 2. List and describe every step of the Scientific Method 1.​ Make observations: Observe your surroundings and find something that interests you or something that catches your attention(a real world problem). 2.​ Defines a problem/question: Create a specific question based on what you observed to begin your investigation. 3.​ Research background information: Gather back group information or anything that can help you answer your question. This is also helps to see if anyone has already asked themself this question and what were their results(make sure your sources are reliable). 4.​ Poses testable hypotheses (plural): Make a prediction or educated guess on what your results will be, formatted as an “if…then…” statement(make sure it is backed up on research). 5.​ Design an experiment: To create an experiment you need to plan and perform, first define your variables: controlled variables that stay the same, independent variables that you manipulate (the cause), and dependent variables that change as a result of the independent variables (the effect). Next, make a list of materials and procedures to guide your experiment. 6.​ Test hypotheses/conduct investigations: Carry out all your procedures/steps to check your hypothesis. 7.​ Generate data: Record and collect data from your experiment and analyze. There are two different types of data, quantitative and qualitative. 8.​ Conduct numerous trials: Repeat the experiment at least twice, this is necessary to make sure it is reliable and consistent, and also helps to identify potential errors. 9.​ Draw conclusions from results: Before drawing any conclusions you must interpret the data, to see if there are any patterns or correlations, when writing the conclusion you will want to summarize your findings and explain why they are important/why should we care, you will restate your hypothesis and state if you were right or wrong and why. You should also tell what were some of the limitations you felt were the most important(money, supplies, working area, etc… Lastly you will want to say how future research can expand findings on your specific topic. 10.​Communicate findings to the rest of the community: Your results are then shared through scientific papers, conferences, or presentations. Communication allows others to critique, replicate, and build upon the work that you’ve done, and increases the world's knowledge. 11.​Get verification from peers: When your experiment is reviewed by qualified individuals, this ensures that your findings are well done and that your experiment can be replicated by others. 12.​Establish models, laws or/and theories: This step is not mandatory but can help others understand what you found better, you can do this by building models, laws, or theories based on results. 3. Qualitative & Quantitative Data -​ Quantitative: means the results are numeric, something you can count or calculate. Examples of this are height, weight, speed, or temperature. -​ Qualitative: means the data is a description of your results, such as the qualities or characteristics, it is what you see, feel, or hear, like colors, textures, smells, or even opinions. 4. Accuracy and Precision -​ Accuracy: refers to how close a measurement is to the actual value. For example, if a dart lands near the bullseye, it’s accurate. -​ Precision: refers to how consistent your measurements are. For example, if darts keep hitting the same spot, but not near the bullseye, it’s precise. 5. Independent and dependent variables & Control group -​ Controlled: the variables that are not manipulated/that stay the same, it is used for comparison.Example: A group of plants kept in normal sunlight while testing other plants in different lighting conditions. -​ Independent: the variables being changed or manipulated/the cause. Example: Amount of sunlight given to plants. -​ Dependent: the variables that change due to the independent variables or that you measure in response/the effect. Example: How tall the plants grow. 6. Bar, Line and Pie Graphs -​ Bar Graph: A graph that uses bars to represent and compare different categories or groups. The length or height of each bar shows the value/quantitative data of that category. Example: If you’re comparing the number of apples, oranges, and bananas sold at a market, each fruit would have a bar, and the height of the bar shows how many were sold. -​ Line Graph: A graph that uses points connected by lines to show how something changes over time. It is used when you want to see trends or patterns over a period of time. Example: If you’re tracking the temperature throughout the day, you’d plot the temperature at each hour and connect the points with a line. -​ Pie Chart: A circular graph divided into slices, where each slice represents a percentage or portion of the whole, the slices always add up to 100%. Example: If you spend your day on school (50%), sleep (30%), and free time (20%), the pie graph would show slices with those proportions. 7. Metric System (SI Units) Base units: -​ Length Unit = meter -​ Mass Unit = kilogram -​ Volume Unit = Liter -​ Temperature = Kelvin or Celsius(Cº) -​ Time = seconds -​ Energy = Joules Prefixes:  -​ Kilo- (k): 10^3 (1 kilometer = 10^3 meters) -​ Hecto- (h): 10^2 -​ Deca- (da): 10^1 -​ Deci- (d): 10^-1 (1 decimeter = 0.1 meters) -​ Centi- (c): 10^-2 (1 centimeter = 0.01 meters) -​ Milli- (m): 10^-3 (1 millimeter = 0.001 meters) ​ If you want to go up a unit you need to divide it by 10, and if you want to go down a unit you need to multiply it by 10. 8. Scientific Notation ​ Is a way to write very large or very small numbers using powers of 10. Format: A number in scientific notation looks like this: a × 10^n -​ a: A number between 1 and 10 (called the coefficient). -​ n: An integer (positive or negative), showing the power of 10. 9. What is Biology? Biology is basically the study of everything that's alive and how it all works. Whether it’s how plants grow, how animals behave, or how our own bodies function. We learn about all kinds of living things, from the tiniest bacteria to the biggest animals, and how they’re all connected. Biology helps us understand the world around us, how life adapts, and why things happen the way they do, like why we get sick or how we evolve over time. Topic 6 Macromolecules 1. List and describe the 2 types of bonds found in water -​ Covalent Bonds: Atoms share electrons (between hydrogen and oxygen) to form the water molecule. -​ Hydrogen Bonds: Weak bonds form between the hydrogen of one water molecule and the oxygen of another, due to their partial charges. Key idea: Covalent bonds hold the water molecule together, while hydrogen bonds connect water molecules to each other. 2. Adhesion Water molecules stick to other surfaces or materials, not just each other.(water sticking to other stuff) Example: Water climbing up a paper towel or plant stem. 3. Cohesion Water molecules stick to each other because of hydrogen bonds. This is why water forms drops and has surface tension.(water sticking to water) Example: Water beads up on a waxed car. 4. Specific Heat -​ This is the amount of heat needed to raise the temperature of 1 gram of water by 1°C. -​ Water has a high specific heat, meaning it takes a lot of energy to heat it up or cool it down. Energy to change temperature. 5. Heat of Vaporization -​ This is the amount of heat needed to turn 1 gram of water from liquid to gas (vapor) at its boiling point. -​ Water has a high heat of vaporization, which means it takes a lot of energy to evaporate it. Energy to turn liquid into gas. 6. Describes what happens to water when it freezes and why When water freezes: - Molecules Slow Down ​ ​ ​ -Hydrogen bonds Lock Molecules ​ ​ ​ -Ice is Less Dense ​ These things happen because the hydrogen bonds create a solid structure when frozen, making ice lighter and less compact than water in its liquid state. 7. Solute, solvent, solution and solubility -​ Solute dissolves. -​ Solvent dissolves it. -​ Solution is the result. -​ Solubility is how well it dissolves. 8. Create a chart listing the polymers and monomers of the macromolecules. Include the bonds in between the monomers and the function of each macromolecule. Macromolecule Monomer Polymer Bond Between Function Monomers Carbohydrates Monosaccharides Polysaccharides Glycosidic Bonds Provide quick (e.g., glucose) (e.g., starch, energy and glycogen) structural support. Proteins Amino Acids Polypeptides Peptide Bonds Catalyze reactions (Proteins) (enzymes), transport, structure, defense. Lipids Glycerol and Fatty Triglycerides, Ester Bonds Store long-term Acids Phospholipids energy, make up  cell membranes, insulation. Nucleic Acids Nucleotides (A, DNA, RNA Phosphodiester Store and transfer T/U, G, C) Bonds genetic information. Topic 7 Enzymes 1. What is an enzyme? A protein that speeds up chemical reactions by lowering activation energy. 2. What is a catalyst? A substance that speeds up reactions without being used up. Enzymes are biological catalysts. 3. What is activation energy? The energy needed to start a chemical reaction. 4. What is denaturing? What factors affect an enzyme? Denaturing is when an enzyme loses its shape and stops working. The factors that affect an enzyme are temperature, pH, substrate concentration, and inhibitors. 5. ATP Metabolic reactions ​ ​ ATP releases energy by hydrolysis, where one phosphate group is released. ATP + H20 —> ADP + Pi (Phosphate group) + Energy. Another metabolic reaction caused by ATP is dehydration synthèse. This is making ATP from ADP. ADP + Pi + Energy —> ATP + H20 Topic 8 Origin of Life 1. Chemical Evolution (Miller-Urey) Life’s building blocks (amino acids) could form from simple chemicals and energy.Miller and Urey recreated early Earth’s conditions in a lab (gases, lightning, and water) and showed amino acids could form. 2. Abiogenesis (Oparin) Life came from simple organic molecules in early Earth's "primordial soup." Oparin proposed that Earth's early oceans had molecules like carbon and nitrogen that gradually formed life over time with energy from the Sun or lightning. 3. Biogenesis Life comes from existing life. Proven by experiments like Louis Pasteur’s (no spontaneous generation of life in sterilized broth). 4. Endosymbiotic Theory Eukaryotic cells (complex cells) evolved when one cell swallowed another. Topic 9 Cells 1. Light Compound Microscope Advantages Light microscopes are cheap, easy, and perfect for studying live cells. 2. Electron Microscope Advantages Electron microscopes are for super close-up, clear images of tiny stuff (but can’t view living things). 3. Dissecting Microscope Uses Dissecting microscopes are perfect for studying bigger objects up close in 3D. 4. Cell Theory 1.​ All living things are made of cells. 2.​ Cells are the basic unit of structure and function in life. 3.​ All cells come from pre-existing cells. 5. Create a chart showing the differences between Prokaryotes and Eukaryotes Feature Prokaryotes Eukaryotes Cell Type Simple, single-celled Complex, single or multi-celled Nucleus No nucleus (DNA is free in Has a true nucleus (DNA cytoplasm) enclosed) Organelles No membrane-bound organelles Has membrane-bound organelles (e.g., mitochondria, ER) Size Smaller Larger Examples Bacteria, Archaea Plants, Animals, Fungi, Protists Reproduction Asexual Sexual or asexual (mitosis, meiosis) DNA Shape Circular DNA Linear DNA (in chromosomes)  Ribosomes Smaller Larger Cytoskeleton Minimal or absent Well-developed cytoskeleton 6. Create a chart showing the differences between Plant and Animal Cells Feature Plant Cells Animal Cells Cell Wall Present (made of cellulose) Absent Shape Rigid, rectangular Flexible, round or irregular Chloroplasts Present (for photosynthesis) Absent Vacuole Large central vacuole (stores Small or absent water/nutrients) Energy Makes glucose through Relies on food for energy photosynthesis Centrioles Absent (usually) Present (for cell division) Lysosomes Rare Common Plasma Membrane Covered by cell wall Outer layer is just the plasma membrane Examples Found in plants and algae Found in animals and humans 7. What are the 4 Components of a cell all organisms have 1.​ Cell Membrane 2.​ Cytoplasm 3.​ DNA 4.​ Ribosomes 8. Describe: Nucleus, nucleolus, nuclear envelope, nucleoplasm Nucleus: The "control center" of the cell.Holds the DNA, which contains the instructions for making proteins and managing cell activities. Nucleolus: A small, dense spot inside the nucleus that makes ribosomes, which build proteins. Nuclear Envelope: A double-layered membrane surrounding the nucleus.Protects the nucleus and controls what goes in or out (like RNA or proteins). Nucleoplasm: The gel-like fluid inside the nucleus.Provides a medium for materials (like DNA and RNA) to move around in the nucleus. 9. Endoplasmic Reticulum: Rough and Smooth Rough ER: -​ Covered in ribosomes (little protein-making machines). -​ Makes and processes proteins. Smooth ER: -​ No ribosomes, smooth surface. -​ Makes lipids (fats), breaks down toxins, and stores calcium. 10. Ribosomes Tiny structures that make proteins by reading genetic instructions (mRNA), found in the cytoplasm, attached to RoughER. 11. Mitochondria The "powerhouse" of the cell, Breaks down food molecules (like glucose) to produce energy (ATP) 12. Chloroplast The green organelle in plant cells, that performs photosynthesis, converting sunlight into glucose (energy for the plant). 13. Vacuole & Vesicles Vacuole: -​ A large storage sac (mainly in plant cells),stores water, nutrients, and waste; helps maintain cell structure. Vesicles: -​ Small membrane sacs found in all cells, transports materials like proteins and lipids within or outside the cell. 14. Golgi Apparatus A stack of flattened sacs that modifies, packages, and ships proteins and lipids made by the ER. 15. Lysosome A sac filled with enzymes (mostly in animal cells), breaks down waste, damaged organelles, or invaders. 16. Plasma Membrane a. Fluid-Mosaic Model: A description of how the plasma membrane is structured. b. Selective Permeability: The plasma membrane lets some substances pass through while blocking others. ​ c. Components: Phospholipids , Proteins , Carbs , Cholesterol. 17. Cell Wall A rigid outer layer found in plant cells, fungi, and bacteria (but not animal cells) that provides structure, protection, and support to the cell. 18. Cytoskeleton (3 components) Cell skeleton with three parts: -​ Microfilaments = Muscles (movement). -​ Intermediate Filaments = Ropes (structure). -​ Microtubules = Highways (transport and movement). 19. Create a chart listing and describing all of the passive and active transports (7 total) Type of Transport Category Description Energy Required? 1. Simple Diffusion Passive Movement of No molecules from high to low concentration. 2. Facilitated Passive Movement of No Diffusion molecules through a membrane protein (still high to low). 3. Osmosis Passive Diffusion of water No molecules across a membrane. 4. Ion Channels Passive Specialized proteins No that allow ions to pass through the membrane. 5. Active Transport Active Movement of Yes (ATP) molecules from low to high concentration using energy. 6. Endocytosis Active The cell engulfs Yes (ATP) large particles or liquids into vesicles.  7. Exocytosis Active Vesicles fuse with Yes (ATP) the membrane to release materials outside the cell. Topic 10 Photosynthesis 1. What are the Reactants and Products of Photosynthesis 6CO2​+ 6H2​O + light energy → C6​H12​O6​+ 6O2 Reactants ​ ​ Products 2. Structure (picture) and Function of Chloroplast Function:Chloroplasts are the site of photosynthesis, where light energy is converted into chemical energy (glucose). 3. Describe the Light Reactions (PSII to PSI) -​ PSII starts it: Splits water, gives electrons. -​ ETC powers it: Makes ATP. -​ PSI finishes it: Recharges electrons, makes NADPH. 4. Describe the 3 steps of the Calvin Cycle 1.​ Carbon Fixation: ○​ CO22​is attached to RuBP (5-carbon sugar) by the enzyme Rubisco. 2.​ Reduction: ○​ ATP and NADPH convert 3-carbon molecules into G3P (a sugar). 3.​ Regeneration: ○​ Some G3P molecules are used to regenerate RuBP, allowing the cycle to continue. 5. What are Cyanobacteria and their effects on Earth Cyano bacteria are tiny bacteria that do photosynthesis, like early versions of plants. Effects on Earth: -​ They released oxygen into the air (first to do this). -​ Made Earth livable for organisms that need oxygen.  -​ Became chloroplasts in plants through teamwork (endosymbiosis). Topic 11 Cellular Respiration 1. Reactants and Products of Cellular Respiration C6​H12​O6​+ 6O2 ​→ 6CO2 ​+ 6H2​O + ATP Reactants ​ ​ Products 2. Describe Glycolysis Breaks glucose, make ATP and pyruvate. 3. Describe Pyruvate Oxidation Turns pyruvate into Acetyl-CoA. 4. Describe Kreb Cycle Generates energy carriers. 5. Describe ETC Uses carriers to make lots of ATP. 6. Describe Fermentation Emergency backup for energy without oxygen. Topic 12 Mitosis 1. Describe all of the details happening at every stage of Interphase (Including Checkpoints) Interphase G1 Phase (Gap 1) ​ What happens: The cell eats macromolecules, then breaks them down to get monomers to build ATP. ​ Checkpoint: The G1 checkpoint checks if the cell is ready for DNA replication (enough resources, no damage). S Phase (Synthesis) ​ What happens: The DNA is synthesized so it can be replicated, and make sister chromatids. Centrosomes move the chromosomes during mitosis.  ​ Checkpoint: The S checkpoint checks if the DNA is replicated correctly. G2 Phase (Gap 2) ​ What happens: The cell continues making proteins for chromosome manipulation. Organelles are duplicated. Cytoskeleton is broken down to make mitosis spindle. ​ Checkpoints: The G2 checkpoint checks for DNA damage and ensures everything is ready for division. 2. Describe all of the details happening at every stage of Mitosis Mitosis 1. Prophase: -​ Chromosomes become more compact -​ Mitotic spindles start to emerge from centrosomes. -​ Nucleolus and Nuclear envelope break down 2. Prometaphase: -​ Chromosomes are still getting more and more compact -​ Mitotic spindle begins to grow into the center of the cell 3. Metaphase: -​ Spindle fibers have fully reached the middle -​ Sister chromatids are lining up in the middle of cell to make metaphase plate -​ Sister chromatids attach to mitotic spindle. 4. Anaphase: -​ Cohesion breaks down -​ Centrosomes start pulling mitotic spindle to pull sister chromatids apart -​ The cell becomes more oval shaped because spindle fibers start to hit plasma membrane 5. Telophase: -​ Mitotic spindles and chromosomes are pulled black to the poles -​ Nuclear envelope and nucleus start to reform -​ Mitotic spindle breaks down 3. Cytokinesis (Plant vs Animal) Not officially part of mitosis, cytokinesis usually happens at the same time as telophase Physical separation of cytoplasm: -​ Plant: new cell wall forms between identical daughter cells -​ Animal: does not allow cell walls to form, so process starts during late anaphase 4. Asexual Reproduction (Binary Fission) Binary Fission = One cell, one copy of DNA, and then it splits into two identical cells. Steps: Copy DNA → Grow → Separate DNA → Split into two. 5. What is Cancer? Cancer is a disease where cells in the body grow and divide uncontrollably. Normally, cells grow, divide, and die in a controlled way. But in cancer, something goes wrong, and the cells keep growing and forming tumors (lumps or masses of tissue) instead of dying when they should. Think of it as: Cancer is like a "broken" cell factory that keeps producing faulty cells without stopping. 6. Somatic Cells Somatic cells are the "everyday" cells that make up the tissues and organs in your body, handling functions like growth, repair, and maintenance. 7. Describe the difference between Homologous Chromosomes vs Sister Chromatids Homologous Chromosomes = One from mom, one from dad, similar but not identical. Sister Chromatids = Identical copies of the same chromosome. Topic 13 Meiosis 1. Describe the difference between Haploid vs Diploid -​ Haploid = One set of chromosomes (sex cells). -​ Diploid = Two sets of chromosomes (body cells). 2. Sexual Reproduction Sexual reproduction is a process where two parent organisms (one male and one female) combine their genetic material (sperm and egg) to produce offspring. The offspring inherit a mix of traits from both parents. 3. Gametes & Germ Cells Gametes: -​ Reproductive cells (sperm in males, eggs in females) that carry half the number of chromosomes (haploid).Gametes combine during fertilization to form a zygote (fertilized egg) with a full set of chromosomes (diploid). Germ Cells: -​ Specialized cells in the reproductive organs (testes in males, ovaries in females) that produce gametes. Germ cells undergo meiosis to create gametes (sperm or eggs). 4. Describe the process of Cross Over/Recombination Crossover is the process during meiosis where homologous chromosomes (the matching chromosomes from each parent) exchange pieces of their DNA. 5. Describe all of the details happening at every stage of Meiosis I Prophase I: Chromosomes pair up and exchange DNA. Metaphase I: Chromosomes line up at the center. Anaphase I: Chromosome pairs are pulled apart. Telophase I: New nuclei form, and the cell prepares to split. Cytokinesis I: The cell divides into two, each with half the chromosomes. 6. Describe all of the details happening at every stage of Meiosis II ​ Prophase II: Chromosomes become visible, and spindle fibers form. ​ Metaphase II: Chromosomes line up at the center. ​ Anaphase II: Sister chromatids are pulled apart. ​ Telophase II: New nuclei form, and the cells prepare to divide. ​ Cytokinesis II: The cells divide, resulting in four haploid gametes. 7. Describe the differences between Mitosis and Meiosis Mitosis = 1 division → 2 identical cells → growth, repair. Meiosis = 2 divisions → 4 unique cells → sexual reproduction. Topic 14 Heredity 1. Describe the procedures and results of Mendel’s Experiment 1. Choice of Organisms: Mendel used pea plants because they had easily observable traits and reproduced quickly. 2. Cross-Pollination: Mendel controlled mating by transferring pollen from one flower to another. 3. Purebred Plants: He began with purebred plants, which consistently passed on the same traits. 4. First Cross (F1 Generation): Mendel cross-pollinated contrasting plants (e.g., tall vs short), and F1 plants showed the dominant trait (e.g., tall). 5. Second Cross (F2 Generation): F1 plants were allowed to self-pollinate, and the F2 generation showed a 3:1 ratio of dominant to recessive traits. 2. Describe Mendel’s Law of (Dominance, Segregation and Independent Assortment) Law of Dominance: Dominant alleles mask recessive ones (e.g., tall (T) masks short (t)). Law of Segregation: Each organism has two alleles for a trait, which separate during gamete formation. Law of Independent Assortment: Genes for different traits are inherited independently. 3. Punnett Squares A statistical model that displays and predicts the different possible allele outcomes from allele combinations (offspring's traits/genes). It involves different types of crosses for different laws. MonoHybrid:A cross between a true breeding red and white plant where red is dominant Dihybrid: A cross between a true breeding red and white plant where red is dominant & black and white seeds where black is dominant. 4. Homozygous vs Heterozygous Homozygous: Both alleles for a trait are the same (e.g., TT or tt). Heterozygous: The alleles for a trait are different (e.g., Tt). 5. Dominant vs Recessive Dominant: The allele that masks the effect of the other (e.g., T for tall). Recessive: The allele that is masked unless both alleles are the same (e.g., t for short). 6. Phenotype vs Genotype Phenotype: The physical appearance or trait (e.g., tall or short). Genotype: The genetic makeup (the actual alleles) of an organism (e.g., TT, Tt, or tt). 7. Characteristics vs Traits vs Alleles Characteristics: General features that describe an organism (e.g., height, eye color). Traits: Specific versions of a characteristic (e.g., tall or short for height). Alleles: Different forms of a gene that determine traits (e.g., T for tall or t for short). 8. Incomplete Dominance Neither allele is completely dominant, so the result is a mix of the two traits. 9. Codominance Both alleles are fully expressed at the same time, not blended. 10. Polygenic Traits Traits controlled by multiple genes, not just one. 11. Multiple Alleles When a gene has more than two possible alleles (different versions of the gene). 12. Sex-linked vs Autosomes Sex-linked: Genes found on the X or Y chromosome. These traits are often passed down differently in males and females. Autosomes: Genes found on non-sex chromosomes (the other 22 pairs of chromosomes). 13. Epistasis One gene can hide or modify the effect of another gene. 14. Sum vs Product Rules (Statistics/Probability) Sum Rule: If two events are mutually exclusive (can't happen at the same time), you add their probabilities. Product Rule: If two events are independent (can happen together), you multiply their probabilities. Topic 15 DNA 1. Griffith experiment Injected mice with harmless (R) and heat-killed deadly (S) bacteria. Harmless bacteria transformed into deadly bacteria when mixed with heat-killed S strain. Discovered that a "transforming principle" (later known to be DNA) could transfer genetic information. 2. Avery experiment Treated heat-killed deadly bacteria with enzymes to remove proteins, RNA, or DNA, and tested transformation. Only DNA caused the transformation of harmless bacteria into deadly bacteria. Concluded that DNA is the "transforming principle" responsible for genetic inheritance. 3. Hershey & Chase experiment Used radioactive markers to track the DNA and protein of viruses infecting bacteria. The virus’s DNA, not its protein, entered the bacterial cell. Confirmed that DNA is the genetic material, not protein. 4. Chargaff Analyzed DNA from different organisms to measure the amounts of bases. Found that the amount of adenine (A) equals thymine (T), and guanine (G) equals cytosine (C). Discovered that A pairs with T, and G pairs with C, showing base pairing in DNA. 5. Watson & Crick model Used X-ray crystallography data and chemical information to build a model of DNA. Proposed that DNA has a double helix structure, with base pairs of A-T and G-C. Determined that DNA’s double helix structure explains how genetic information is stored and replicated. 6. Structure (Picture) & Function of DNA Functions: -​ DNA stores genetic information. -​ It provides the instructions to make proteins. -​ It helps cells reproduce by passing on genetic information to new cells. 7. Describe the process of Replication (Helicase, Primase, DNA Polymerase, Ligase) Helicase unwinds the DNA double helix. Primase adds RNA primers to the DNA strands. DNA polymerase adds new nucleotides to form the new DNA strands. Ligase connects the fragments on the lagging strand, ensuring both strands are fully replicated. 8. Semi-conservative Semi-conservative means that one half of the DNA in each new molecule is the conserved DNA, and the other half is new, this ensures the genetic information is accurately passed on to the next generation of cells. 9. Chromosomal mutations -​ Aneuploidy (Insertion & Deletion names): Abnormal number of chromosomes (too many or too few). -​ Inversion (Para vs Pericentric): A section of the chromosome is flipped around. -​ Translocation: A piece of a chromosome moves to a different chromosome. -​ NonDisjunction: Chromosomes don’t separate properly during cell division, leading to extra or missing chromosomes. 10. Effects of mutations (Somatic vs Germline) -​ Somatic mutations affect only the individual (not passed to offspring) and can cause diseases like cancer. -​ Germline mutations are inherited by offspring and can lead to genetic disorders. 11. Genetic Variation Genetic variation is crucial for the survival and evolution of species, as it provides the diversity necessary for adaptation to changing environments. 12. Neutral vs Beneficial vs Negative mutations -​ Neutral mutations have no impact on survival or reproduction. -​ Beneficial mutations provide an advantage and can increase an organism’s chance of survival or reproduction. -​ Negative mutations cause harm, reducing the organism’s ability to survive or reproduce. 13. Epigenetics Epigenetics is the study of how gene expression can be modified without changing the DNA sequence. It involves chemical changes to DNA or histones that can turn genes on or off. Epigenetic changes can be influenced by environmental factors and can play a role in development, health, and disease. 14. What are the differences and similarities between RNA and DNA Feature DNA RNA Full Name Deoxyribonucleic acid Ribonucleic acid Sugar Contains deoxyribose (a sugar Contains ribose (a sugar with without one oxygen atom) one more oxygen atom) Structure Double-stranded, forming a Single-stranded double helix Bases Adenine (A), Thymine (T), Adenine (A), Uracil (U), Cytosine (C), Guanine (G) Cytosine (C), Guanine (G) Function Stores genetic information (the Helps in protein synthesis and blueprint of life) gene regulation Location in Cell Found mainly in the nucleus Found in the nucleus and cytoplasm Stability More stable (can last longer in Less stable, breaks down quickly the cell) after use