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Biology Grade 12 - Unit 1 Biochemistry.
What is an organic molecule ✔✔Organic molecule are the molecules of life. The four main groups are Carbohydrates, lipids, Nucleic acids & Proteins
What is the difference between intramolecular forces and intermolecular forces? ✔✔Intermolecular forces are the bonds that exist between two molecules, while intramolecular forces are the forces that hold atoms together inside a molecule.
What is a covalent bond? A polar covalent bond? ✔✔A covalent bond involves the sharing of electrons between atoms. What would make it polar is if there is an uneven sharing of electrons between the atoms.
Why is a water molecule polar? ✔✔Water is a polar molecule due to the difference in electronegativity between the oxygen and hydrogen atoms. The oxygen atom is slightly negative, while the hydrogens are slightly positive.
What are hydrogen bonds? ✔✔Hydrogen bonding is a weak form of bonding between a slightly negative oxygen atom in an H20 molecule, and a slightly positive hydrogen atom in an H molecule.
What are hydrophobic interactions? ✔✔Hydrophobic reactions are the relations between water and hydrophobs, for example; fat and water.
What are functional groups? ✔✔Functional groups are groups of atoms which act as landmarks to help us classify and identify different compounds.
What advantage does structural formula have over molecular formula? ✔✔Molecular formula only shows us the numbers of atoms in each element, while structural formula shows us how they are arranged.
What is a macromolecule? ✔✔A macromolecule is a molecule with a very large amount of atoms, ex: most polymers
What are monomers? Polymers? ✔✔A monomer can be bonded to other identical molecules to form a polymer.
What are carbohydrates? ✔✔Carbohydrates act as a short-term energy storage. They are composed of Carbon, Hydrogen & Oxygen. They often contain many hydroxyl groups. Most are polar & will dissolve in water.
What is meant by calling glucose, fructose, and galactose isomers? ✔✔Glucose, fructose and galatose are isomers because they have the the same molecular formula, but their structural formula is different from one another.
What is a monosaccharide? ✔✔A monosaccaride are simple sugars that consist of one sugar unit that cannot be further broken down into simpler sugars.
Where to the bonds form between the 2 monosaccharides that make up a disaccharide? What type of bond is it? ✔✔The bond that forms to create a disaccharide is called Dehydration Synthesis. It occurs when the hydroxyl group is removed from one monosaccharide, and one hydrogen atom is removed from the other, creating a new H20 molecule.
What is a polysaccharide? ✔✔A polysaccharide is a chain of many monosaccharides bonded together through dehydration synthesis.
What are the differences and similarities between starch, glycogen, and cellulose? ✔✔Starch, glycogen, and cellulose are all monomers of glucose. They differ in the type of glucose present and the bonds which link the glucose monomers together.
What are lipids? ✔✔Lipids are composed of Carbons, hydrogens and oxygen atoms. Their main functions include acting as long term energy storage and provide insulin which help to protect organs. They are mostly hydrophobic and do not dissolve in water.
What are triglycerides? What are the bonds formed between the 2 components of a triglyceride?
✔✔A triglyceride are one glycerol molecule, and three fatty acid chains. Formed through dehydration synthesis. Function groups present include Hydroxyl groups on the glycerol molecule, and carboxyl groups on the fatty acid's.
What is the difference between a saturated fatty acid and an unsaturated fatty acid? ✔✔A saturated fatty acids means all the carbon's on the carbon chain are fully 'saturated' with hydrogen atoms making the lipid more solid. An unsaturated fatty acid means the carbons were not fully saturated with hydrogen atoms and a double bond was formed to create a "kink" in the structure of the lipid making it more liquid.
Why should one limit the amount of saturated fats in their diet? ✔✔Saturated fats are bad for you because of their linear structure, can pack more tightly and stay along the walls of your arteries.
What are phospholipids? How does their structure differ from a triglyceride? ✔✔Phospholipids are the same aa a triglyceride except that instead of three fatty acid chains, phospholipids only have two.
reactions are not strong enough to break the peptide bonds, the primary structure remains the same.
What are nucleic acids? What do they do? What are the 2 types? ✔✔Nucleic acids include RNA, DNA, & mRNA. Nucleic acids are made of nucleotides. The 5 man nucleotides are uracil, cytosine, thymine, adenine, and guanine. They help cells replicate and build proteins.
What is the basic structure of a nucleotide monomer? ✔✔A phosphate group, a sugar, and one of five nitrogenous bases.
How are RNA and DNA different? ✔✔DNA's sugar is deoxyribose, while RNA's sugar is ribose. DNA has the bases a,t,g,c while RNA has the bases a, u, g, c
What types of bonds link adjacent nucleotides? ✔✔Dehydration synthesis between one molecules hydroxyl on the sugar group, to another's molecules phosphate group.
List the four types of important biological reactions we discussed. Provide a brief explanation and example for each one. ✔✔Neutralization RXN- rxn between and acid & a base that results in the formation of salt. Redox RXN- Oxidation (process involving a molecule losing electrons, & Reduction (process involving a molecule gaining electrons) Condensation RXN - an H atom is removed from a function group on one monomer, and an OH group is removed from the other. Removal of an h20 molecule. Hydrolysis RXN - breakdown of macromolecules, reverse condensation rxn. Addition of a water molecule.
What is an enzyme? How does it work? ✔✔An enzyme has an area in it called the active site, which creates a hole in the enzyme. The substrate then fits into the active site. The substrate is what's being broken down. In every single chemical reaction, there has to be an enzyme associated with them to speed up that reaction. Activation energy turns on those enzymes, while inhabitation energy turns them off.
What factors can affect enzyme activity and how? ✔✔Temperature, pH, enzyme concentration, substrate concentration, and the presence of activation or inhibition energy.
Explain the difference between competitive and non-competitive inhibition in enzyme regulation. ✔✔A competitive inhibitor will block the enzyme's active site, a non competitive inhibitor will bind to the substrate somewhere other than the active site; an allosteric site.
Explain the endomembrane system of protein modification and transport. ✔✔The golgi apparatus has golgi enzymes which can add saccharides to proteins, so they become glycoproteins, so they can be used other places in the cell or outside the cell.
Explain the Fluid Mosaic Model of the cell membrane. ✔✔Fluid Mosaic Model, the 'fluid" part represents how parts of the membrane can move around freely. The mosaic part illustrates the patchwork of proteins that is found in the phospholipid bilayer.
What affects the fluidity of the phospholipid bilayer of the membrane? ✔✔Temperature, cholesterol, saturated/unsaturated.
What is the role of proteins in the cell membrane? ✔✔Proteins inside the cell membrane can function as enzymes, act as receptors, or transport material across the cell membrane.
What is the difference between active and passive transport? ✔✔Passive transport does not require ATP, while active transport requires ATP
What is diffusion? What factors affect the rate of diffusion? ✔✔Diffusion is the action of molecules moving from an area of high concentration to an area of lower concentration. Kinetic energy, particle size, temp, concentration difference, distance, can all affect the rate of diffusion.
What is osmosis? When comparing to aqueous solutions, what does it mean to say that one is hypotonic and the other is hypertonic? ✔✔Osmosis is when particles diffuse over a semi- permeable membrane from a lower concentration to higher. Hypotonic solution is when there are more molecules going into the cell than out. Hypertonic is the opposite.
In facilitated diffusion, what is the difference between carrier proteins and channel proteins? ✔✔Carrier proteins transport molecules, while channel proteins transport ions.
What molecule provides most of the energy required for active transport? ✔✔Glucose; produces 36-38 molecules of ATP
What is the difference between primary and secondary active transport? ✔✔In primary transport the energy is derived directly from the breakdown of ATP. Secondary, the energy is derived from energy that has been stored in the form of ion concentration.
What are the three types of endocytosis? ✔✔Phagocytosis, Pinocytosis, and receptor-mediated endocytosis
A vesicle full of waste materials is travelling through the cytoplasm towards the cell membrane. How does the cell get rid of the waste in the vesicle and what is this process called?
✔✔Exocytosis; the golgi complex packages macromolecules into transport vesicles that travel to fuse with the plasma membrane. THis fusion causes the vesicle to spill its contents out of the cell.
Allosteric Site ✔✔The site on an enzyme that is not the active site, where other molecules can interact with and regulate the activityof the enzyme by causing a change in the information of the enzyme
Activator ✔✔A molecule that binds to the allosteric site of an enzyme and that keeps an enzyme active or causes an increase in the activity of that enyzme
Passive Transport ✔✔A movement of biochemicals and other atomic or molecular substances across cell membranes without need of energy imput
Concentration Gradient ✔✔The process of particles, which are sometimes called solutes, moving through a solution or gas from an area with a higher number of particles to an area with a lower number of particles.
Diffusion ✔✔Process by which molecules intermingle as a result of their kinetic energy of random motion.
Facilitated Diffusion ✔✔Process of spontaneous passive transport of molecules or ions across a cells membrane via specific transmembrane integral proteins.
Active Transport ✔✔The movement of molecules across a cell membrane from a region of their lower concentration - in the direction against some gradient or other distructing factor. ( Requires energy)
Endocytosis ✔✔A form of active transport in which a cell transports molecules into the cell by engulfing them in an energy-using process.
Exocytosis ✔✔A process by which a cell transports secretory products through the cytoplasm to the plasma membrane.
Hydroxyl Group ✔✔
Amino Group ✔✔
Carboxyl Group ✔✔
Carbonyl Group ✔✔
Sulfhydryl Group ✔✔
Phosphate Group ✔✔
Isotope ✔✔Atoms of the same element that have different numbers of neutrons
Radioisotopes ✔✔An isotope that has an unstable nucleus and undergoes radioactive decay
Monomers ✔✔A chemical subunit that serves as a building block of a polymer.
Monosaccharide ✔✔A single sugar molecule such as glucose or fructose, the simplest type of sugar.
Triglycerides ✔✔Is composed of three fatty acids, and a glycerol molecule.
Phospholipid ✔✔Same as a triglyceride except it has only two fatty acid tails, rather than three.
Steroids ✔✔Made of four rings of carbon.
Waxes ✔✔A type of lipid molecule consisting of one fatty acid linked to an alcohol; functions as a waterproof coating on many biological surfaces such as apples and other fruits.
Polypeptide ✔✔long chain of amino acids that makes proteins
Peptide Bond ✔✔The chemical bond that forms between the carboxyl group of one amino acid and the amino group of another amino acid
Ester Linkage ✔✔the bond between a fatty acid and a glycerol that forms a lipid
Cell membrane ✔✔Is a barrier A cell structure that controls which substances can enter or leave the cell. It is made of phospholipids, proteins, carbs, and cholesterol.
Nucleus ✔✔A part of the cell containing DNA and RNA and responsible for growth and reproduction. It is made of an outer membrane, inner membrane, nucleoplasm, nucleolus, chromatin, & nuclear enevelopes.
Endoplasmic Reticulum ✔✔A system of membranes that is found in a cell's cytoplasm and that assists in the production, processing, and transport of proteins and in the production of lipids. Its studded with with ribosomes, while smooth ER is made of smooth slipper fats.
Ribosomes ✔✔Makes proteins. The are made from complexes of RNA's and proteins.
