AC-HPAT Biology Exam Marking Scheme

AC-HPAT Biology Exam Marking Scheme Macromolecules - ANSWER- A very large organic molecule composed of many smaller molecules passive transport - ANSWER- the movement of substances across a cell membrane without the use of energy by the cell (diffusion) active transport - ANSWER- Energy-requiring process that moves material across a cell membrane against a concentration difference catalyst - ANSWER- substance that speeds up the rate of a chemical reaction fluid mosaic model - ANSWER- model that describes the arrangement and movement of the molecules that make up a cell membrane Effect of qualitative factors on rate of diffusion of molecules across a plasma membrane? - ANSWER- The higher the temperature, the more kinetic energy the particles will have, so they will move and mix more quickly. Structure and function of carbohydrate - ANSWER- sugars and starches that the body uses for energy. Consists of carbon, hydrogen, and oxygen. Typically in a 1:2:1 ratio What are the tree main types of carbohydrates - ANSWER- 1. Monosaccharides - simple sugars ( ie glucose, 6 carbon, fructose and galactose) 2. Disaccharides which are double sugars ( ie sucrose, maltose, lactose) (consist of two monosaccharides bonded together through a dehydration synthesis reaction [ results in loss of water molecule] ) 3. Polysaccharides which are complex sugars ( many monosaccharides bonded together) ( starch, glycogen, and cellulose) Structure and function of protein - ANSWER- made from many amino acids connected together in different arrangements, provide the building materials your body needs to grow and repair itself Enzymes - ANSWER- Proteins that speed up chemical reactions ( act as catalysts) Structure and function of Lipids - ANSWER- Store energy. Consist mainly of carbon, hydrogen, and oxygen. Do not dissolve in water, because they are non polar ( electrons are shared equally in the molecule ) -Fatty acids containing no double bonds are saturated. -Fatty acids containing one double bond are mono-unsaturated. -Fatty acids containing two or more double bonds are polyunsaturated. -Fats provide approximately 9 kcal/g. Lysosomes - ANSWER- An organelle containing digestive enzymes. Destroy pathogens (white blood cells) Vacuoles - ANSWER- Stores food, water, wastes, and other materials Mitochondria - ANSWER- Powerhouse of the cell, organelle that is the site of ATP (energy) production. Cellular respiration's occurs here cell / plasma membrane - ANSWER- A cell structure that controls which substances can enter or leave the cell. Ribosomes - ANSWER- site of protein synthesis Rough Endoplasmic Reticulum - ANSWER- System of internal membranes within the cytoplasm. Next to the nucleus & continuous with the nuclear envelope. Membranes are rough due to the presence of ribosomes. Produce proteins and fold them into three dimensional shape.( some are used in ER and other are used in other part of cell) before transporting them using vesicles. Smooth Endoplasmic Reticulum - ANSWER- An endomembrane system where lipids and carbohydrates are synthesized as well as hormones and cholesterol, calcium levels are regulated, and toxic substances are broken down ( detox occurs) . Golgie bodies/apparatus - ANSWER- 1. Receives vesicles and modifies proteins 2. Adds lipids and carbs 3. Responsible for protein exportation cellular respiration formula - ANSWER- C6H12O6 + 6O2 ------ 6CO2 + 6H20 + Energy (ATP) What is cellular respiration? - ANSWER- Complicated process that releases energy from food in the presence of oxygen Three stages of cellular respiration - ANSWER- glycolysis, krebs cycle, electron transport chain Glycolysis - ANSWER- the breakdown of glucose by enzymes, releasing energy and pyruvic acid. Krebs cycle - ANSWER- The cycle harnesses the available chemical energy of acetyl coenzyme A (acetyl CoA) into the reducing power of nicotinamide adenine dinucleotide (NADH). The TCA cycle is part of the larger glucose metabolism whereby glucose is oxidized to form pyruvate, which is then oxidized and enters the TCA cycle as acetylCoA. electron transport chain - ANSWER- a series of proteins in which the high-energy electrons from the Krebs cycle are used to convert ADP into ATP How do enzymes aid digestion? - ANSWER- Enzymes are proteins that speed up chemical reactions ( and digestion) They break down food into smaller, simple molecules that can be absorbed into the blood stream. Eukaryote - ANSWER- A cell that contains a nucleus and membrane bound organelles