front 1 Homeostasis: | back 1 The process by which organisms maintain a stable internal environment despite changes in external conditions. This involves feedback mechanisms that regulate body temperature, pH, glucose levels, etc. |
front 2 Diffusion: | back 2 A passive process where molecules move from an area of higher concentration to an area of lower concentration. In single-celled organisms, diffusion directly exchanges gases and nutrients with the environment. In multicellular organisms, diffusion occurs across cell membranes and within tissues to distribute oxygen, nutrients, and waste products. |
front 3 Homeostasis | back 3 The process by which organisms maintain a stable internal environment despite changes in external conditions. |
front 4 Diffusion | back 4 A passive process where molecules move from an area of higher concentration to an area of lower concentration. |
front 5 Sensory Neurons | back 5 Transmit sensory information from receptors to the central nervous system (CNS). |
front 6 Motor Neurons | back 6 Carry signals from the CNS to muscles and glands. |
front 7 Interneurons | back 7 Connect sensory and motor neurons within the CNS. |
front 8 Dendrites | back 8 Receive signals from other neurons. |
front 9 Cell Body (Soma) | back 9 Contains the nucleus and organelles. |
front 10 Axon | back 10 Transmits electrical impulses away from the cell body. |
front 11 Synaptic Terminals | back 11 Release neurotransmitters to communicate with other neurons. |
front 12 Synapse | back 12 The junction between two neurons where neurotransmitters are released to transmit signals. |
front 13 Action Potential | back 13 A rapid change in membrane potential that travels along the axon. |
front 14 Glial Cells | back 14 Support neurons by providing nutrients, removing waste, and insulating axons with myelin sheaths. |
front 15 Central Nervous System (CNS) | back 15 Comprises the brain and spinal cord. |
front 16 Peripheral Nervous System (PNS) | back 16 Includes all nerves outside the CNS. |
front 17 Reflexes | back 17 Automatic responses to stimuli that involve sensory neurons, interneurons, and motor neurons. |
front 18 Sensory Cells | back 18 Specialized cells that detect stimuli and convert them into electrical signals. |
front 19 Touch | back 19 Mechanoreceptors in the skin. |
front 20 Vision | back 20 Photoreceptors (rods and cones) in the retina. |
front 21 Hearing | back 21 Hair cells in the cochlea. |
front 22 Smell | back 22 Olfactory receptors in the nasal cavity. |
front 23 Taste | back 23 Taste buds on the tongue. |
front 24 Membrane Channels | back 24 Ion channels that open or close in response to stimuli, initiating sensory transduction. |
front 25 Opsins | back 25 Light-sensitive proteins in photoreceptors that play a key role in vision. |
front 26 Foveal Vision | back 26 Sharp central vision with high acuity. |
front 27 Peripheral Vision | back 27 Detects motion and provides a broader field of view. |
front 28 Brain | back 28 Processes sensory information to create perceptions and responses. |
front 29 Skeletal Muscle | back 29 Voluntary muscles attached to bones. |
front 30 Cardiac Muscle | back 30 Involuntary muscle found in the heart. |
front 31 Smooth Muscle | back 31 Involuntary muscles in the walls of internal organs. |
front 32 Muscle Fibers | back 32 Composed of myofibrils containing actin and myosin filaments. |
front 33 Cross-Bridge Cycle | back 33 The process where myosin heads bind to actin, pull, and release, powered by ATP. |
front 34 Calcium | back 34 Triggers muscle contraction by binding to troponin, which moves tropomyosin to expose binding sites on actin. |
front 35 Antagonist Muscles | back 35 Muscle pairs that work opposite each other to move bones (e.g., biceps and triceps). |
front 36 Gas Exchange | back 36 Oxygen is taken in, and carbon dioxide is expelled. |
front 37 Ventilation | back 37 The process of moving air in and out of the lungs. |
front 38 Gills | back 38 Extract oxygen from water. |
front 39 Tracheae | back 39 Air-filled tubes in insects. |
front 40 Lungs | back 40 Organs for gas exchange in terrestrial animals. |
front 41 Negative Pressure Breathing | back 41 Diaphragm contraction creates a vacuum that draws air into the lungs. |
front 42 Hemoglobin | back 42 A protein in red blood cells that binds oxygen; its affinity for oxygen is affected by pH and CO2 levels. |
front 43 Myoglobin | back 43 Stores oxygen in muscle cells for use during intense activity. |
front 44 Circulatory System | back 44 Transports nutrients, gases, and wastes throughout the body. |
front 45 Open Circulatory System | back 45 Hemolymph bathes organs directly. |
front 46 Closed Circulatory System | back 46 Blood is confined to vessels. |
front 47 Heart | back 47 Pumps blood. |
front 48 Arteries | back 48 Carry blood away from the heart. |
front 49 Veins | back 49 Return blood to the heart. |
front 50 Capillaries | back 50 Sites of material exchange. |
front 51 Blood Flow | back 51 Path through the cardiovascular system, including the pulmonary and systemic circuits. |
front 52 Material Exchange | back 52 Occurs primarily in capillaries. |
front 53 Heart Contraction | back 53 Coordinated by the sinoatrial (SA) node and atrioventricular (AV) node. |
front 54 Herbivores | back 54 Eat plants. |
front 55 Carnivores | back 55 Eat other animals. |
front 56 Omnivores | back 56 Eat both plants and animals. |
front 57 Diet Components | back 57 Carbohydrates, proteins, fats. |
front 58 Essential Minerals | back 58 Required for various bodily functions. |
front 59 Essential Amino Acids | back 59 Must be obtained from the diet. |
front 60 Vitamins | back 60 Organic compounds needed in small amounts. |
front 61 Undernutrition vs. Malnutrition | back 61 Lack of sufficient calories vs. lack of essential nutrients. |
front 62 Ingestion | back 62 Taking in food. |
front 63 Digestion | back 63 Breaking down food into absorbable units. |
front 64 Absorption | back 64 Nutrients enter the bloodstream. |
front 65 Elimination | back 65 Expelling undigested material. |
front 66 Alimentary Canal | back 66 The digestive tract from mouth to anus. |
front 67 Mouth | back 67 Begins mechanical and chemical digestion. |
front 68 Salivary Glands | back 68 Produce saliva to moisten food. |
front 69 Epiglottis and Glottis | back 69 Prevent food from entering the trachea. |
front 70 Stomach | back 70 Secretes acid and enzymes to digest food. |
front 71 Small Intestine | back 71 Absorbs nutrients. |
front 72 Pancreas | back 72 Produces digestive enzymes and bicarbonate. |
front 73 Liver | back 73 Produces bile to emulsify fats. |
front 74 Gallbladder | back 74 Stores and releases bile. |
front 75 Large Intestine | back 75 Absorbs water and forms feces. |
front 76 Appendix | back 76 A vestigial structure with immune functions. |
front 77 Innate Immunity | back 77 Nonspecific defense mechanisms. |
front 78 Adaptive Immunity | back 78 Specific responses to pathogens. |
front 79 MHC I | back 79 Present on all nucleated cells; presents to cytotoxic T cells. |
front 80 MHC II | back 80 Present on antigen-presenting cells; presents to helper T cells. |
front 81 Macrophages | back 81 Engulf and digest pathogens. |
front 82 Dendritic Cells | back 82 Present antigens to T cells. |
front 83 Neutrophils | back 83 First responders to infection. |
front 84 Helper T Cells | back 84 Activate other immune cells. |
front 85 Cytotoxic T Cells | back 85 Kill infected cells. |
front 86 Natural Killer Cells | back 86 Destroy virus-infected and cancerous cells. |
front 87 B Cells | back 87 Produce antibodies. |
front 88 Antibodies | back 88 Bind to antigens to neutralize them. |
front 89 T Cell Receptors | back 89 Recognize antigens presented by MHC molecules. |
front 90 Cytokines | back 90 Signaling molecules that regulate immune responses. |
front 91 Vaccines | back 91 Stimulate the immune system to develop immunity to specific pathogens. |
front 92 Hormones | back 92 Chemical messengers that regulate physiological processes. |
front 93 Water-Soluble Hormones | back 93 Bind to receptors on the cell surface. |
front 94 Lipid-Soluble Hormones | back 94 Pass through cell membranes and bind to intracellular receptors. |
front 95 Endocrine Glands | back 95 Include the pituitary, thyroid, adrenal glands, etc. |
front 96 Hypothalamus and Pituitary | back 96 The hypothalamus controls the pituitary, which regulates other endocrine glands. |
front 97 Calcium Regulation | back 97 Parathyroid hormone increases blood calcium levels. |
front 98 Short-Term Stress Responses | back 98 Mediated by the adrenal medulla (epinephrine and norepinephrine). |
front 99 Long-Term Stress Responses | back 99 Mediated by the adrenal cortex (cortisol). |
front 100 Ammonia | back 100 Highly toxic, requires a lot of water to excrete, common in aquatic animals. |
front 101 Urea | back 101 Less toxic, requires less water, common in mammals, amphibians, and some fish. |
front 102 Uric Acid | back 102 Least toxic, conserves water, common in birds, reptiles, and insects. |
front 103 Cortex | back 103 Outer layer containing nephrons. |
front 104 Medulla | back 104 Inner region with renal pyramids. |
front 105 Renal Pelvis | back 105 Funnel-shaped structure that collects urine. |
front 106 Glomerulus | back 106 A network of capillaries where blood filtration begins. |
front 107 Bowman's Capsule | back 107 Encases the glomerulus and collects the filtrate. |
front 108 Proximal Tubule | back 108 Reabsorbs nutrients, ions, and water from the filtrate. |
front 109 Loop of Henle | back 109 Concentrates urine by reabsorbing water and salts. |
front 110 Distal Tubule | back 110 Further adjusts the composition of the filtrate. |
front 111 Collecting Duct | back 111 Final site for water reabsorption, leading to the renal pelvis. |