QCAA Biology 2023 Units 1-4
Flashcards for all 4 units and topics of QCAA Biology
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QCAA Biology 2023 Units 1-4 - Leaderboard
QCAA Biology 2023 Units 1-4 - Details
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256 questions
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| Why do small single celled organisms have a high surface area to volume ratio? | Allows them to rely on oxygen and material diffusing into the cell. The higher the surface area to volume ratio they have, the more effective this process can be. |
| Why do small single celled organisms have a high surface area to volume ratio? | Allows them to rely on oxygen and material diffusing into the cell. The higher the surface area to volume ratio they have, the more effective this process can be. |
| Why do small single celled organisms have a high surface area to volume ratio? | Allows them to rely on oxygen and material diffusing into the cell. The higher the surface area to volume ratio they have, the more effective this process can be. |
| Why do small single celled organisms have a high surface area to volume ratio? | Allows them to rely on oxygen and material diffusing into the cell. The higher the surface area to volume ratio they have, the more effective this process can be. |
| Define the cell membrane structure | Consists of a phospholipid bilayer with their tails pointing inward, which forms a barrier between two aqueous compartments. |
| Define the structure of phospholipid bilayers | Consists of two layers of phospholipids, with a hydrophobic, interior and a hydrophilic exterior. The hydrophilic (polar) head group and hydrophobic tails (fatty acid chains) are depicted in the single phospholipid molecule. |
| Why do small single celled organisms have a high surface area to volume ratio? | Allows them to rely on oxygen and material diffusing into the cell. The higher the surface area to volume ratio they have, the more effective this process can be. |
| Define the structure of cholesterol | Cholesterol is a 27 carbon compound with a hydrocarbon tail, a central sterol nucleus made of four hydrocarbon rings, and a hydroxyl group. |
| Define glycoproteins | Proteins containing glycans attached to amino acid side chains. |
| What is the function of a protein channel? | Acts as a pore in the membrane that lets water molecules or small ions through quickly. |
| Define diffusion | The movement of individual molecules of a substance through a semipermeable barrier from an area of higher concentration to an area of lower concentration. |
| Define osmosis | The movement of a solvent (such as water) through a semipermeable membrane into a solution of higher solute concentration. |
| Define active transport | A mode of transportation in plants, which uses stored energy to move the particles against the concentration gradient. |
| Define endocytosis | The process by which cells take in substances from outside of the cell by engulfing them in a vesicle |
| Define phagocytosis | The process by which a cell uses its plasma membrane to engulf a large particle |
| Define hydrophobic | A property of a substance that repels water |
| Define hydrophilic | A molecular entity that is attracted to water |
| Why do small single celled organisms have a high surface area to volume ratio? | Allows them to rely on oxygen and material diffusing into the cell. The higher the surface area to volume ratio they have, the more effective this process can be. |
| What are prokaryotes? | A single-celled organism that lacks a nucleus, and other membrane-bound organelles. |
| What are eukaryotes? | Organisms whose cells have a nucleus enclosed within a nuclear envelope. |
| What is the difference between pro and eukaryotic cells? | Eukaryotic cells have a membrane-bound nucleus and prokaryotic cells do not. Prokaryotes are significantly smaller than eukaryotes |
| What are the requirements for cell survival? | Energy sources, simple nutrients, removal of wastes, acids, ions and water. |
| What is cellular respiration? | Metabolic reactions that convert chemical energy from nutrients into adenosine triphosphate, and then release waste products. |
| Define the mitochondria | Membrane-bound cell organelles that generate most of the chemical energy needed to power the cell's biochemical reactions. |
| Define the chloroplast | Membrane-bound organelle known as a plastid that conducts photosynthesis |
| Define the rough endoplasmic reticulum | Connected flattened sacs, part of a continuous membrane organelle within the cytoplasm of eukaryotic cells, that plays a central role in the synthesis of proteins. |
| Define the lysosome | Organelles that contain enzymes that break down all types of biological polymers—proteins, nucleic acids, carbohydrates, and lipids. |
| What is the formula for total magnification? | Multiply the magnification power of the ocular lens by the power of the objective lens. |
| What is the formula for field of view? | Field Number ÷ Objective Magnification |
| Identify the following structure: | Chloroplast |
| Identify the following structure: | Rough endoplasmic reticulum |
| Identify the following structure: | Mitochondria |
| Identify the following structure | Lysosome |
| Define plastids | Double-membrane organelles which are found in the cells of plants and algae. Plastids are responsible for manufacturing and storing of food. |
| Define the smooth endoplasmic reticulum | It synthesizes lipids, phospholipids as in plasma membranes, and steroids |
| Define an enzyme | Proteins that act as biological catalysts by accelerating chemical reactions. |
| Define the structure of an enzyme | A linear chain of amino acids, which give rise to a three-dimensional structure. |
| Define the function of an active site | A part of an enzyme to which substrates bind and where a reaction is catalysed. |
| What are the two enzyme models? | The 'lock and key' model and 'induced fit' model. |
| What factors impact an enzyme? | Temperature, pH, and concentration. |
| Define ATP | (Adenosine Triphosphate) A substance present in all living cells that provides energy for many metabolic processes and is involved in making RNA. |
| What is glucose? | The primary sugar in the blood and is the major source of energy for the body's cells |
| Define photosynthesis | The process by which plants use sunlight, water, and carbon dioxide to create oxygen and energy in the form of sugar |
| Define light dependant reactions | A photochemical reaction taking place in the thylakoid membranes of chloroplasts, where light energy is transformed into adenosine triphosphate (ATP) and nicotinamide adenine dinucleotide phosphate (NADPH) |
| Define light independent reactions | A series of biochemical reactions in photosynthesis not requiring light to proceed, and ultimately produce organic molecules from carbon dioxide. |
| Define glycolysis | The breakdown of glucose by enzymes, releasing energy and pyruvic acid. |
| Define fermentation | A metabolic process that produces chemical changes in organic substrates through the action of enzymes. |
| Define the electron transport chain | A cluster of proteins that transfer electrons through a membrane within mitochondria to form a gradient of protons that create adenosine triphosphate |
| Define Krebs cycle | A sequence of reactions in which oxidation of acetic acid provides energy for storage in phosphate bonds |
| Define aerobic respiration | A chemical process in which oxygen is used to make energy from carbohydrates. |
| Define anaerobic respiration | Creating energy without the presence of oxygen |
| Define stem cells | Stem cells are the body's “master cells.” They are the building blocks of all organs, tissues, blood and the immune system. |
| Define unspecialised cells | Stem cells. They can differentiate to make multiple types of cells |
| Define cell differentiation | The process in which a stem cell alters from one type to a differentiated one |
| Define potency in stem cells | The varying ability of stem cells to differentiate into specialized cell types. |
| Define capillaries | Capillaries are blood vessels. They transport blood, nutrients and oxygen to cells in your organs and body systems. |
| Define alveoli | Air sacs at the end of the bronchioles. The alveoli are where the lungs and the blood exchange oxygen and carbon dioxide during the process of breathing in and breathing out. |
| What are bronchioles? | A tiny branch of air tubes in the lungs. |
| Define gas exchange | The physical process by which gases move passively by diffusion across a surface. |
| Define haemoglobin | A protein of red blood cells that contains iron and carries oxygen from the lungs to the tissues and carbon dioxide from the tissues to the lungs. |
| What common features do structures involved with gas exchange have? | Large surface area relative to the volume of the organism. Thin (have a short diffusion pathway) A moist surface (so gases can dissolve first before they diffuse in or out) |
| Define the villi | Tiny hair-like projections that line the inside of the small intestine. They contain blood vessels and help absorb nutrients. |
| Define the function of digestive enzymes | These proteins speed up chemical reactions that turn nutrients into substances that your digestive tract can absorb. |
| Define a nephron | A nephron is the structural and functional unit of the kidney. It regulates the concentration of water and minerals such as sodium by filtering the blood and reabsorbing the important nutrients. |
| What is the structure of a nephron? | Glomerulus, Bowman’s capsule, proximal and distal tubules, Loop of Henle, collecting tubule |
| Define the function of the Loop of Henle | To recover water and sodium chloride from urine. |
| Define selective reabsorption | The process where molecule are reabsorbed from the filtrate as they pass through the nephron. |
| Define the function of glomerulus | The glomerulus filters your blood |
| Define the function of the proximal tubules | Reabsorption of filtrate in accordance with the needs of homeostasis |
| Define the function of the distal tubules | Regulating extracellular fluid volume and electrolyte homeostasis. |
| Define the function of the collecting tubule | Transportation of urine and absorption of water |
| Define homeostasis | A state of balance among all the body systems needed for the body to survive and function correctly. |
| Define negative feedback | When the product of a reaction leads to a decrease in that reaction. |
| What are the types of sensory receptors? | Chemo, thermos, mechano, photo, noci receptors |
| Define effectors | An effector molecule selectively binds to a protein and regulates its biological activity. |
| Define metabolism | The chemical changes that take place in a cell or an organism. |
| Define thermoregulation | A mechanism by which mammals maintain body temperature with tightly controlled self-regulation independent of external temperatures. |
| Define osmoregulation | A process that regulates the osmotic pressure of fluids and electrolytic balance in organisms. |
| Define catabolism | Chemical or enzymatic reactions involved in the breakdown of organic or inorganic materials such as proteins, sugars, fatty acids, etc. |
| Define anabolism | Process in metabolism where the simple molecules combine to generate complex molecules. |
| Define neurons | Basic functional units of the nervous system, and they generate electrical signals called action potentials, which allow them to quickly transmit information over long distances. |
| What are the types of neurons? | Sensory, motor, and interneurons. |
| Define sensory neurons | Sensory nerves carry signals to your brain to help you touch, taste, smell and see. |
| Define motor neurons | Motor nerves carry signals to your muscles or glands to help you move and function. |
| Define interneurons | They connect motor and sensory neurons and send signals between neurons. |
| What are the parts of a neuron? | Dendrites, soma, body, axon, myelin sheath, nodes of Ranvier, axon terminal and synapse. |
| Define action potential | A temporary shift (from negative to positive) in the neuron's membrane potential caused by ions suddenly flowing in and out of the neuron. |
| Define synaptic transmission | Process by which a neuron communicates with a target cell across a synapse. |
| Define hormones | Chemical substances that act like messenger molecules in the body. |
| Define receptors | A molecule inside or on the surface of a cell that binds to a specific substance and causes a specific effect in the cell. |
| Define the circulatory system | The system that contains the heart and the blood vessels and moves blood throughout the body |
| Define the lymphatic system | The lymphatic system is our body's 'sewerage system'. It maintains fluid levels in our body tissues by removing all fluids that leak out of our blood vessels. |
| Define upregulation | An increase in the number of receptors on the surface of target cells, making the cells more sensitive to a hormone or another agent. |
| Define downregulation | The process of reducing or suppressing a response to a stimulus |
| Define signal transduction | The process by which a cell responds to substances outside the cell through signalling molecules found on the surface of and inside the cell. |
| Define endotherms | Those that maintain a constant body temperature independent of the environment. |
| Define ectotherms | Organisms that are dependent on external sources of body heat. |
| What are the four thermoregulation mechanisms? | Convection, radiation, conduction, evaporation |
| What does insulin do in thermoregulation? | Insulin acts on the hypothalamic thermally responsive neurons to induce hyperthermia by promoting an increase in heat production and/or vasoconstriction. |