Bio 2 Exam Study Guide PDF

Topic 3 Study Guide: What are hydrolysis reactions? What is the purpose of these reactions? Hydrolysis is a chemical reaction where water is used to break down a compound. This typically involves the splitting of a bond in the molecule, adding a water molecule. The purpose is to decompose comple...

Topic 3 Study Guide: What are hydrolysis reactions? What is the purpose of these reactions? Hydrolysis is a chemical reaction where water is used to break down a compound. This typically involves the splitting of a bond in the molecule, adding a water molecule. The purpose is to decompose complex molecules like polymers into monomers, making them more accessible for varioud biological procceses. What are condensation or dehydration reactions? What is the purpose of these reactions? Condensation reactions also known as dehydration reactions, involve joining of two molecules with the realse of a water molecule. The purpose is these reations are essential for synthesizing larger molecules like polymers from monomers, contributing to the formation of macromolecules like protien, nucleic acids, and carbohydrates. De ne polymer and monomer. What is the relationship between the two? Polymer: is a large molecule made up of repeating monomers Monomer: is a small, single molecule that can join together with other similar molecules to form a polymer. Their relationship is monomers are the building blocks of polymers. through condensation reactions, monomers link together to form long chains known as polymers. What type of chemical reations adds monomers together to lengthen polymers? What type of chemical reaction removes monomers to shorten polymers? Condensation reactions add monomers together to lengthen polymers Hydrolysis reactions remove monomers to shorten polymers Carbohydrates What are the monomers of carbohydrates called? The polymers? The monomers of carbohydrates are called monosaccharides, while the polymers are called polysaccharides De ne Monosaccharide. What is the major function of a monosaccharide in living organisms? Monosaccharides are a simple sugar (glucose) that serves as a primary energy source for living organisms De ne Polysaccharide, and give the function of the two main types (storage vs structural) Polysaccharide: a carbohydrate polymer made of many monoccharides Storage polysaccharides store energy while structural provide support fi fi fi Name the two types of storage polysaccharides (fuel storage in plants and fuel storage in animals) Plants: starch (composed of amylose and amylopectin) Animals: Glycogen Difference between Amylose and Amylopectin Amylose: a linear polymer of glucose(unbranched) Amylopectin: A branced polymer of glucose What is the name of the structrual polysaccharides found in plants and disccused in class? Cellulose is the primary structual polysaccharide found in plants What are sugar isomers? Make sure you are able to de ne two sugars are isomers from each other. Sugars that have the same molecular formula but different structural arrangements to determine if two sugars are isomers check if they have the same chemical formula but different structures C6H12O6 What is the name of the covalent bond that joins two sugars together? Glysosidic bond What are amylases and maltases? What macromolecule do they break down and what are the products? Where in the body are they produced? Amylases: break down starch into smaller suagrs like maltose Maltases: speci cally break down maltose into glucose They break down carbohydrates they produce simpler sugars like maltose or glucose Amylases are produces in the saliva and pancreas, while maltase is produced in the small intestine Proteins What are the monomers of proteins called? The polymers? What is the name of the covalent bond that joins amino acids together? The monomers of proteins are called amino acids, while polymers are polypeptides or proteins. The covalent bond that joins two amino acids together are called a peptide bond. What are the three groups that can be found attached to the central carbon of an amino acid? How do amino acids differ from each other? How many standard amino acids exist? The three groupd that can be found attached to the central carbon of an amino acoid is amino fi fi group, carboxyl group, and side chain  Amino acids differ from each other primarily based on the structure and characteristics of their side chains. Their are 20 standard amino acids Amino acids are grouped in 4 different groups based on the chemistry of the side chain. Make sure you know the groups. Make sure you are able to determine, if given a structure, to which group an amino acid belongs to. For example, determine to which group the amino acid below belongs How are protein structure and function related? Protein structure is directly related to its function. The speci c arrangement of amino acids detedetermines the protein shape, which in turn affects how it interacts with other molecules. A protein must have the correct structure to preform its biological function Name and de ne the four levels of protein structure, and indicate which bonds are important at each level. Primary Structure: The sequence of amino acids in a polypeptide chain. Bonds: Peptide bonds. Secondary Structure: The folding or coiling of the polypeptide chain into structures like alpha helices or beta sheets. Bonds: Hydrogen bonds between backbone atoms. Tertiary Structure: The overall 3D shape of a single polypeptide chain, determined by interactions among side chains (R groups). Bonds: Hydrogen bonds, ionic bonds, disul de bridges, and hydrophobic interactions. Quaternary Structure: The arrangement of multiple polypeptide chains (subunits) into a single functional protein. Bonds: Same as tertiary—hydrogen bonds, ionic bonds, disul de bridges, and hydrophobic interactions. De ne Denaturation. Discuss why this is important to the function of proteins, and provide some of the factors that can cause proteins to denature Denaturation: is the process by which a protein loses its native structure, resulting in the loss of its biological function Its importance is crucial because a proteins function is dependent on its speci c shape Some factors that cause proteins to denature is the changes in tempurature, pH, or exposures to chemicals Nucleic Acids Name the two types of nucleic acids and give their functions. DNA: Stores genetic information fi fi RNA: Involved in protein synthesis and gene regulation What are the monomers of nucleic acids called? The polymers? Monomers: Nucleotides Polymers: Nucleic acids What is the name of the covalent bond that holds nucleotides together? A phosphodiester bond What is the name of the chemial bonds that hold two strands of polynucleotides together? Hydrogen bonds Explain why a strand of nucleotide has 2 different ends. What are those ends? A strand of nucleptides has a 5' end (phosphate group) and a 3' end (hydroxyl group). This orientation is crucial for replication and transcription What are three important groups that can be found within a nucleotide? How do the nucleotides differ from each other? What bases constitute DNA and RNA? How are the nucleotides of DNA and RNA different? The three groups that can be found within a nucleotide is a phosphate group, a sugar, a nitrogenous base Nucleotides differe by their nitrogenous base Describe the structure of a DNA molecule. How is a RNA molecule similar and how is it different from DNA? DNA is a double helix composed of two strands of nucleotides running in opposite directions, with complementary base pairing Similarities: RNA is also made of nucleotides and can form structures Differences: RNA is usually single stranded, has ribose sugar, and contains uracil instead of thymine Which DNA nucleotides pair up when two DNA polynucleotides come together? (in other words, what are the base pairing rules between DNA bases Adenine pairs with thymine (A-T) Cytosine pairs with guanine (C-G) Lipids What is the one characteristic that all lipids share? All lipids are hydrophobic or amphipathic, meaning they do not mix well with water  What are the two smaller molecules that a “fat” is composed of? Give the “of cial” name of a fat, and discuss the difference between a saturated and unsaturated fat Fats are composed of glycerol and fatty acids Of cal name: Triglycerides Saturated fats have no double bonds between carbon atoms (solid at room temperature), while unsaturated fats have one or more double bonds (liquid at room temperature) Describe a phospholipid, focusing on its two different “ends” and its main function in cells. Hint: phospholipids are important components of the plasma membrane A phospholipid has a hydrophilic "head" (phosphate group) and two hydrophobic "tails" (fatty acids). Its main function is to form the bilayer of cell membranes, allowing for compartmentalization. Compare the structure of a fat and a phospholipid Fats: compose of one glycerol and three fatty acids Phosopholipid: compse of one glycerol, two fatty acids, and a phosphate group What is a steroid. Give the function of at least one steroid discussed in class. Hint: This steroid is a component of the cell membrane. A steroid is a type of lipid with characteristic four ring structure Function: Choloesterol is a steroid that helps maintain membrane uidity in cell membranes Topic 4 Cells Know the names, functions and structures of cellular organelles Nucleus: Contains genetic material; surrounded by a nuclear envelope with pores. Ribosomes: Sites of protein synthesis; composed of RNA and proteins, found free in the cytoplasm or attached to the rough endoplasmic reticulum (ER). Endoplasmic Reticulum (ER): Rough ER: Studded with ribosomes; involved in protein synthesis and processing. Smooth ER: Lacks ribosomes; synthesizes lipids and detoxi es harmful substances. Golgi Apparatus: Modi es, sorts, and packages proteins and lipids for transport. Mitochondria: Powerhouse of the cell; produces ATP through cellular respiration; double- membraned with its own DNA. Lysosomes: Contain digestive enzymes to break down waste; involved in cellular recycling. Peroxisomes: Contain enzymes for breaking down fatty acids and detoxifying harmful substances. Cytoskeleton: Network of bers providing structural support and aiding in cell movement. fi fi fi Explain the concept of protein traf cing. Why is this process important for cells? Concept: Protein traf cing refers to the process by which proteins are synthesized, modi ed, sorted, and transported to their destinations within or outside the cell Importance: This process is crucial for maintating cellular functions, ensuring proteins reach their correct locations, and facilitating communication and response to enviormental changes What are endocytosis and exocytosis? Why are these two processes important for cells. Endocytosis: The process by which cells engulf substances from external enviorment, forming vesicles to bring materials into the cell. Exocytosis: The process by which cells expel materials in vesicles that fuse with the plasma membrane, releasing their contents outside the cell Importance: Both processes are vital for nutrient uptake, waste removal, and communication between cells Compare prokaryotic and eukaryotic cells. Explain the similarites and difference between the two types. Similarities: Both types of cells have a plasma membrane, cytoplasm, and ribosomes Differences: Nucleus, Eukaryotic cells have a true nucleus, prokaryotic cells do not Size, Prokarotic cells are smaller. Organelles, eukaryotic cells have membrane bound organelles prokaryotic do not. DNA structure: Prokaryotic DNA is circular and located in the nucleoid region; eukaryotic DNA is linear and housed within the nucleus Instead of nucleus, bacteria cells have a nucleoid Describe the differences between bacteria and eukaryotic chromosomes Bacteria: Have a single, circular chromosome located in the nucleoid Eukaryotes: Have multiple linear chromosomes contained within a nucleus Cell organelles in plant cells but not in animal cells Chloroplasts, cell wall, and central vacuole Topic 5 Viruses Are viruses cells? No, viruses are not cells. They are acelluar entities that cannot carry out metabolic processes independently. Viruses require a host cell to replicate and express their genetic material Viruses are obligate parasitic entities. Explain what this means. Viruses are considered obligate parasitic entities because they can only replicate inside a fi fi living host cell. They hijack the hosts cellular machinery to reproduce, making them entirely dependent on the host for their lifecycle List and describe the components of the viral particle. Capsid: A protein shell that encloses and protects the viral genetic material. Genetic Material: Either DNA or RNA, which contains the viral genome. Envelope (in some viruses): A lipid membrane derived from the host cell membrane, often containing viral proteins. Spikes: Protein structures on the surface of the virus that facilitate attachment and entry into host cells. Based on their morphology, viruses can be classi ed as: helical, polyhedral, spherical, and complex. Make sure you are able to recognize to which group a virus will belong to. Provide ONE example of each type. Helical: Rod-shaped with a coiled structure. Example: Tobacco Mosaic Virus (TMV). Polyhedral: Often spherical with a geometric shape. Example: Adenovirus. Spherical: Roughly spherical and may have an envelope. Example: In uenza Virus. Complex: Have irregular shapes and structures. Example: Bacteriophage T4. What is a viral receptor? What is its function? What is the viral receptor that the SARS-CoV-2 viruses use to enter a human cell? A viral receptor is a speci c molecule on the surface of a host cell that viruses use to attach and enter the cell. The viral receptor is ACE2 Do all viruses contain DNA genomes? List all possible types of genomes different viruses might have. No, not all viruses contain DNA genomes. Double-stranded DNA (dsDNA) Single-stranded DNA (ssDNA) Double-stranded RNA (dsRNA) Single-stranded RNA (ssRNA) (which can be positive-sense or negative-sense) Describe the genome of the SARS-CoV-2 virus (size and type of nucleic acid) SARS-CoV-2 has a single-stranded RNA (ssRNA) genome, approximately 30,000 nucleotides in length. It is classi ed as a positive-sense RNA virus, meaning its RNA can directly serve as mRNA for protein synthesis. fi fi fi  Topic 6 Membrane Transport (Diffusion & Osmosis) Which types of molecules can easily pass through the plasma membrane? Which cannot? For those that cannot, what type of protein do they need help from? Distinguish between channel and carrier proteins Easily Pass: Small nonpolar molecules(oxygen,carbon dioxide) and lipid-soluble substances can easily pass through the plasma membrane Cannot Pass: Large polar molecules(glucose) and ions(Na, K) cannot pass freely through the membrane For molecules that cannot pass through, they require help from transport proteins Channel Proteins: these form pores that allow speci c ions or water to pass through Carrier Proteins: these bind to speci c molecules and undergo a conformational change to transport them across the membrane Diffusion occurs when solutes move from areas of high concentration to low concentration until they are spread evenly in the available space (or down their concentration gradient). Does this require an input of energy? What is it called when a substance diffuses (without any help) across a biological membrane? Diffusion does not require an input of energy; it occurs naturally as solutes move from areas of high concentration to low concentration. When a substance diffuses across a biological membrane without assistance, its calle a simple diffusion De ne osomosis. In which direction will water move? Osomosis is the diffusion of water acroos a semipermeable membrane. Water will move toward the area of higher solute concentration to acheieve equilibrium What is tonicity? More speci cally, what does it mean if the solution surrounding a cell is isotonic? Hypertonic? Hypotonic? Isotonic: The solution has the same solute concentration as the cells interior, resulting in no net movement of water Hypertonic: the solution has a higher solute concentration than the cell, causing water to move out of the cell (cell shrinks) Hypotonic: the solution has a lower solute concentration than the cell, causing water to move into the cell (cell swells and may burst) fi fi fi fi How does faciliated diffusion work? In which direction do solutes move during this type of transport? Faciliated diffusion is the transport of substances across a membrane with the help of transport proteins. Solutes move down their concentration gradient (from high to low) without energy input Active Transport: is the movement of solutes against their concentration gradient ( from low to high). This process requires energy typically from ATP. Cells use active transport to maintain ion concentrations, uptake nutrients, and expel waste Sodium-potassium pump: is an active transport mechanism that pumps sodium ions (Na) out of the cell and potassium ions (K) into the cell. Typically, sodium concentration is higher outside the cell, while potassium concentration is higher inside the cell Membrane proteins can be uniporters, symporters, and antiporters. What does that mean? Uniporters: Transport one type of molecule across the membrane Symporters: Transport two types of molecules in the same directions Antiporters: Transport two different types of molecules in opposite directions