Life Science - Biology Semester 1 Exam Review Outline December 2024 PDF

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This is a study guide for a Semester 1 Life Science - Biology exam, scheduled for December 2024. The document covers key vocabulary and concepts in chemistry and biology, and likely includes definitions and examples, aiding exam preparation.

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**[Life Science - Biology ]** **[Semester 1 Exam Review Outline]** **[December 2024]** **[Made by Alisa Liashkova]** **[(I know I will fail this test once again no matter what I do :/)]** **[(NOTE: We're allowed to use the notecard at home and the word bank sheet of paper can be brought too) ]*...

**[Life Science - Biology ]** **[Semester 1 Exam Review Outline]** **[December 2024]** **[Made by Alisa Liashkova]** **[(I know I will fail this test once again no matter what I do :/)]** **[(NOTE: We're allowed to use the notecard at home and the word bank sheet of paper can be brought too) ]** Main vocabulary words we need to know+meanings - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - **[Legend: ]** **[Pink- topic]** **[Green- additional topic]** **[Blue-chapter]** **[Chemistry in Biology - Chapter 6]** Compounds - Difference between compounds and elements An element is - a pure substance that cannot be broken down physically or chemically into other substances. The element is produced by - only one type of atom. There are currently - 118 known elements where 92 of which occur naturally. Each element has a - unique name and symbol. **Periodic Table of Elements:** Horizontal rows are called - periods. Vertical columns are called - groups. **Types of Elements:** Metals- The elements identified as metals tend to donate electrons. Nonmetals- The elements identified as nonmetals tend to accept electrons. - A pure substance is formed when - two or more different elements combine Compounds are always formed from - a specific combination of elements in a fixed ratio. Compounds cannot be - broken down into simpler compounds or elements by physical means. **Types of bonds:** Covalent bond- A chemical bond that forms when electrons are shared between the atoms. A molecule is - a compound in which the atoms are held together by covalent bonds(like in a picture below) ![ch 6 im 8](media/image26.png) The forces that are necessary to the structure and behavior of molecules across various states of matter are called - van der Waals Forces van der Waals Forces - When molecules come close together, the attractive forces between slightly positive and negative regions pull on the molecules and hold them together.The strength of the attraction depends on the size of the molecule, its shape, and its ability to attract electrons. Ionic bond - An electrical attraction between two oppositely charged atoms or groups of atoms. (like in a picture below) ![ch 6 im 9](media/image53.png) Some atoms tend to - donate or accept electrons more easily than other atoms. The elements identified as metals tend to - donate electrons. The elements identified as nonmetals tend to - accept electrons. Most ionic compounds are crystalline at - room temperature Most ionic bonds have - higher melting points than molecular compounds formed by covalent bonds. **In sum:** - - Chemical Reactions A chemical reaction is - the process by which atoms or groups of atoms in substances are reorganized into different substances. Clues that a chemical reaction has taken place include - the production of heat or light and formation of a gas, liquid, or solid. (like in 2 pictures below) Chemical reaction: Physical reaction: ch 6 im 13 chemical change![ch 6 im 13 physical change](media/image44.png) Chemical reactions are essential for - life processes, such as metabolism and energy production. - Reactants are - the **starting substances**, on the left side of the arrow. Products are - the **substances formed during the reaction**, on the right side of the arrow. - formula 14a - - - ![](media/image56.png) **Endothermic Reaction:** - - Exothermic reaction's energy of the product is - lower than the energy of the reactants. Exothermic reaction does what with the energy? - **releases** the heat energy Endothermic reaction's energy of the products is - higher than the energy of the reactants Endothermic does what with the energy? - **absorbs** the heat energy - - Activation energy is - the minimum amount of energy needed for reactants to form products in a chemical reaction. Catalyst - a substance that lowers the activation energy needed to start a chemical reaction. It does not increase how much product is made and it does not get used up in the reaction. \- Enzymes Catalyst - a substance that lowers the activation energy needed to start a chemical reaction. It does not increase how much product is made and it does not get used up in the reaction. What are enzymes? - They are biological catalysts that speed up chemical reactions in living organisms. Enzymes are typically proteins with specific 3D shapes that allow them to bind to reactants. ch 6 im 19 - Active site - the specific location where a substrate binds on an enzyme. - ![ch 6 im 20 and 21](media/image12.png) The active site helps the reactants by - changing shape and forming the enzyme-substrate complex, which helps in the reactants to be broken and new bonds to form. - Substrates - the reactants that bind to the enzyme - A substrate is a molecule upon which an enzyme acts. Enzymes are proteins that speed up chemical reactions in the body by binding to substrates at their active sites. This interaction forms an enzyme-substrate complex, leading to a chemical reaction that transforms the substrate into different molecules called products Substrates are essential for enzyme-catalyzed reactions. The enzyme binds to the substrate, facilitating a reaction that converts it into products. This process is crucial for various bodily functions, including digestion and metabolism Enzyme Specificity: Each enzyme is specific to its substrate, meaning it will only work with particular molecules. This specificity ensures that biochemical reactions occur correctly and efficiently - - What factors affect enzyme activity? - pH, temperature, and other substance When enzyme doesn't function, it - denatures (or goes down in the graph) - - - - pH- the measure of concentration of H^+^ in a solution - - - - - - - Water's Polarity - All biological and regular molecules that have an unequal distribution of charges are called - polar molecules Polarity - the property of having two opposite poles. Water is a polar molecule, meaning it has a partial positive charge on one side and a partial negative charge on the other. This allows for hydrogen bonding - Hydrogen bonding is a special type of attraction between molecules, not a true chemical bond like covalent or ionic bonds. It occurs when a hydrogen atom, which is partially positively charged, is attracted to a nearby electronegative atom like oxygen, nitrogen, or fluorine. This interaction can happen between different molecules (intermolecular) or within the same molecule (intramolecular) - - - Hydrogen bond is - a weak interaction involving a hydrogen atom and a fluorine, oxygen, or nitrogen atom. Electrons can form - bonds Bond is - combination of valence electrons of an element with other valence electrons of the same or different element, and one electron pair combination termed as one or single bond and two electrons pair combination is termed as two or double bond and so on. The bond is made out of compounds. - Cohesion & Adhesion: Cohesion is water molecules sticking to each other; adhesion is water molecules sticking to other surfaces **Adhesion -** When two different substances or molecules face the force of attraction this force is known as adhesion force. It has the ability to stick water molecules to other substances. A strong adhesion force causes the liquid to - spread all over the surface. Adhesion is caused by - electrostatic or mechanical forces that exist among two kinds of different substances. An example of adhesion is - Water drops on the surface of leaves and flowers. **Cohesion -** When two same substances or molecules face the force of attraction this force is known as cohesion force. Each water molecule forms hydrogen bonds with neighboring molecules. Cohesion has the ability of water molecules to stick to each other. Cohesion is caused by - hydrogen bonding and Van der Waals forces. A strong force of cohesion forms - water droplets on any surface. An example of cohesion is - water - **Solvent Properties -** Water\'s polarity makes it an excellent solvent, dissolving many substances. Solvation is - the process by which solvent molecules surround and interact with solute molecules Solutes that are able to be dissolved by a solvent are considered to be - soluble (insoluble substances will not form a solution) Water can dissolve many substances, making it essential for life processes Water is commonly referred to as - the universal solvent due to its capacity to dissolve a large number of substances Water can dissolve any substance that contains - charged particles (ions) or electronegative atoms (polarity) - Mixtures Mixture is - a combination of two or more pure substances in which each pure substance retains its individual chemical properties. Mixtures can be composed of solids, liquids, or gases. Mixtures are made out of - compounds Types of mixtures- Heterogeneous Mixture and Homogenous Mixture Homogenous Mixture - A mixture that form when a solute dissolves completely in a solvent. Heterogeneous Mixture - A mixture where the components remain distinct(separated).![ch 6 im 27 heterogeneous](media/image14.png) - Solute - the substance that is dissolved in the solvent. A homogeneous mixture where the solute is dissolved in the solvent. - Solvent - a substance in which another substance is dissolved. - Solute - the substance that is dissolved in the solvent. Acids and Bases Buffers- mixtures that can react with acids or bases to keep the pH within a particular range Acids release H⁺ ions in solution, while bases release OH⁻ ions. The pH scale measures how acidic or basic a solution is. ch 6 im 28 ![ch 6 im 23](media/image23.png) - - Acids are - the substances that release **hydrogen ions (H^+^)** when dissolved in water. pH- the measure of concentration of H^+^ in a solution - Bases are - the substances that release **hydroxide ions (OH^--^)** when dissolved in water. Macromolecules Macromolecules are formed by joining smaller organic molecules together. Macromolecules are large, complex molecules essential to life. They are built from smaller units called monomers and include four major classes: carbohydrates, lipids, proteins, and nucleic acids. Each class plays distinct and essential roles in living organisms. - **Function:** Carbohydrates serve as a primary energy source and provide structural support in organisms.Monomers: Monosaccharides (simple sugars) are the building blocks of carbohydrates (and are nucleotides) Made of carbon, hydrogen, and oxygen in a 1:2:1 ratio. They provide energy and structural support. - ![](media/image13.png) - - - - - - - **Triglycerides (Fats and Oils):** Lipids include fats and oils; saturated fats have single bonds, while unsaturated fats have double bonds. - - - Carbohydrates: Look for ring structures with oxygen and multiple -OH groups (e.g., glucose). Lipids: Long hydrocarbon chains or fatty acid tails, with or without a glycerol backbone. Proteins: Amino acids linked by peptide bonds. Look for the central carbon, amino group, carboxyl group, and variable R-group. Nucleic Acids: Phosphate group, sugar (ribose or deoxyribose), and nitrogenous bases (A, T, C, G, U). - - - ![](media/image20.jpg) - Uses the molecular model kits to build the fat molecule called a **[triglyceride]**.
 \*Notice that it contains one glycerol and three fatty acids! - - Function: Proteins are involved in nearly every cellular function, including catalysis, structure, signaling, transport, and movement. Enzymatic Activity: Enzymes like amylase catalyze biochemical reactions, increasing reaction rates without being consumed. Structural Support: Proteins like collagen provide tensile strength to connective tissues; keratin strengthens hair and nails. Transport: Hemoglobin transports oxygen in the blood; membrane proteins facilitate the transport of ions and molecules across cell membranes. Signaling: Hormones like insulin regulate physiological processes; receptor proteins transmit signals from the environment to the cell\'s interior. Movement: Actin and myosin are involved in muscle contraction and cellular movement. Defense: Antibodies protect against disease by identifying and neutralizing pathogens. Made of amino acids; they perform various functions like catalysis (enzymes) and transport (hemoglobin) - ![F:\\BSC 1005 - Survey\\resources\\jpgs labled\\ch05\\figure\_05\_17\_nb.jpg](media/image9.jpg) - - - - - - Function: Nucleic acids store and transmit genetic information; they are also involved in protein synthesis. Monomers: Nucleotides are the building blocks of nucleic acids. DNA and RNA, composed of nucleotides. DNA contains A, T, C, G bases; RNA contains A, U, C, G - Base Pairing: Adenine pairs with Thymine (A-T) via two hydrogen bonds. Cytosine pairs with Guanine (C-G) via three hydrogen bonds. The hydrogen bonds between DNA strands occur between specific pairs of nitrogenous bases: T only pairs with A, and C only pairs with G. This specificity comes from the shapes of the bases and their chemical properties. Because the DNA strands are matched according to these base pairing rules, the strands are said to be **complementary**. ![](media/image24.png) - RNA, or ribonucleic acid, is a crucial molecule in biology, primarily involved in the synthesis of proteins. It is composed of four nitrogenous bases: adenine (A), uracil (U), cytosine (C), and guanine (G). These bases are essential for the structure and function of RNA. RNA Bases --------- - - - - **[Chapter 12 ]** DNA Structure DNA often is compared to a twisted ladder. 
 Double helix formed by two antiparallel strands. Sugar-phosphate backbone on the outside. Nitrogenous bases paired on the inside. Base Pairing: Adenine pairs with Thymine (A-T) via two hydrogen bonds. Cytosine pairs with Guanine (C-G) via three hydrogen bonds. Stores genetic information for the development and functioning of living organisms. DNA is a double helix composed of nucleotides with bases A-T and C-G pairing through hydrogen bonds DNA Replication Semi-conservative replication is the mechanism by which DNA is copied, ensuring that each new DNA molecule consists of one original parent strand and one newly synthesized strand. This method preserves the genetic information and maintains the integrity of the genome across generations. Occurs during the S phase of the cell cycle. Enzymes like helicase unwind DNA, while DNA polymerase adds new nucleotides - DNA helicase, an enzyme, is responsible for unwinding and unzipping the double helix. 
 How does replication actually get going at the forks? **Helicase** is the first replication enzyme to load on at the origin of replication. Helicase\'s job is to move the replication forks forward by \"unwinding\" the DNA (breaking the hydrogen bonds between the nitrogenous base pairs). Proteins called **single-strand binding proteins** coat the separated strands of DNA near the replication fork, keeping them from coming back together into a double helix.RNA primase adds a short segment of RNA, called an RNA primer, on each DNA strand. DNA polymerase continues adding appropriate nucleotides to the chain by adding to the 3′ end of the new DNA strand.DNA polymerases are responsible for synthesizing DNA: they add nucleotides one by one to the growing DNA chain, incorporating only those that are complementary to the template. - - - - ![](media/image17.png) DNA polymerase removes the RNA primer and fills in the place with DNA nucleotides. 
 DNA Transcription - The process where RNA polymerase makes mRNA from DNA in the nucleus. - - RNA Translation mRNA is decoded by ribosomes in the cytoplasm to produce proteins. tRNA helps match mRNA codons with amino acids - - - - - - - *[Keep in mind for the above processes:]* ***-Where** these processes take place -* *-What **enzymes** are involved in each -* *-Other **structures** that are involved -* *-Final **products** that are produced -* Discovery of the Genetic Material - - Achievement: Developed the double-helix model of DNA. Model Features: Two antiparallel strands. Complementary base pairing. Explained DNA replication mechanism - 1. 2. 3. Franklin: - - - - - Photo 51: Franklin\'s X-ray diffraction image revealing DNA\'s helical structure. In sum: Watson and Crick discovered the double helix structure of DNA with contributions from Franklin\'s X-ray diffraction data Mutation - - - - - ![ch 12 im 40](media/image29.png) - - - - - - - - - **[Chapter 13.2, 13.3]** Genetic Engineering Tools - - - - - - - - - - - - - [[gel electrophesis demo]](https://www.youtube.com/watch?v=ZDZUAleWX78) - - - - Biotechnology - - - - - - - \- Risks, Benefits Benefits -------- 1. 2. 3. 4. 5. Risks ----- 1. 2. 3. 4. Overall, while transgenic plants and animals offer many benefits, they also come with significant risks that need careful consideration and management. \- Example of an that has been genetically modified - - - Human Genome Project - **[Cell Structure and Function - Chapter 7]** 1. Life can be found as: - - - - - - - - - All living things are composed of cells, which are the basic unit of life. New cells arise from existing cells 2. a. **Light passes through a specimen** **Two lenses form image** 3. b. c. d. Use transmitted light where light must pass through object on the slide Position and movement of the image is [opposite] from the object Used for thin-sections Light microscopes use light to magnify specimens; electron microscopes use electron beams for greater detail i. e. 4. 5. 6. 7. 8. Disadvantage: sample must be dead and sliced very thin and stained 2\. **[Scanning Electron Microscope (SEM):]** Electrons are directed over the surface of the sample producing a 3 dimensional image. 9. 10. 11. ![http://www.jeol.com/Portals/0/prodshots/EO/jem-2100f.jpg](media/image41.jpg) 12. f. Lack a nucleus; have simple structures like cell walls and ribosomes. ii. procaryotecell.jpg g. Have a nucleus and organelles like mitochondria and endoplasmic reticulum iii. iv. Prokaryotic - - - - - - - - Eukaryotic - - - - - - - - - - ![http://www.shmoop.com/images/biology/biobook\_cells\_1.png](media/image7.png) 13. Prokaryote 14. 15. 16. 17. 18. 19. 20. 21. h. **Eukaryote** 22. 23. 24. 25. 26. 27. 28. 29. i. 30. ![](media/image64.jpg) 31. Describes the cell membrane structure with a phospholipid bilayer containing proteins that control substance entry/exit j. k. 32. - - - - - Cell Transport Passive transport processes where molecules move from high to low concentration areas without energy use. Require energy to move substances against concentration gradients or transport large molecules into/out of cells a. - The movement of solute particles from a high concentration to low b. 1. c. d. 2. e. 3. 4. 5. 6. f. i. 1. 2. ii. 1\. Isotonic solution: 7. 8. ![ch7 7-4 q3a](media/image25.png)ch 7 im 30b iii. 3\. Hypertonic 9. 10. 11. iv. 2\. Hypotonic solution: - - - - Comparing all solutions: ![http://www.phschool.com/science/biology\_place/biocoach/images/biomembrane1/Tonic2.gif](media/image61.gif)http://2.bp.blogspot.com/\_10M5kCPMTYM/S-1kTAlmmrI/AAAAAAAAABc/Duc-LSzYgyU/s1600/Bio+hypotonic,+Isotonic,+Hypertonic.gif g. 12. 13. h. v. ![E:\\LESSON OVRVW batch 2\\art\\BIO10NAE\_03\_07\_04\_005\_LRIM\_14.png](media/image43.png) i. - - - - - - endocytosis![phago](media/image31.jpg) **Exocytosis:** - **Cells releasing large amounts of material from the cell** - **The membrane of the vacuole surrounding the material fuses with the cell membrane, forcing the contents out of the cell** E:\\LESSON OVRVW batch 2\\art\\BIO10NAE\_03\_07\_04\_005\_LRIM\_15.png ![endocytosis](media/image54.png)

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