Biology 151 List of Terms Fall 2024 PDF

**Fall 2024 - Exam 3** **Biology 151 List of Terms** **Dr. Madison** *Updated 12/9/24* **[Fri. Nov. 8 Structure and Function: Homeostasis]\ Physiology -** The study of the functions of living things - focuses on the underlying mechanisms of body process; also closely related to anatomy - the stu...

**Fall 2024 - Exam 3** **Biology 151 List of Terms** **Dr. Madison** *Updated 12/9/24* **[Fri. Nov. 8 Structure and Function: Homeostasis]\ Physiology -** The study of the functions of living things - focuses on the underlying mechanisms of body process; also closely related to anatomy - the study of structure and function **tissue types (epithelial, connective, muscle, nervous)-** a. b. c. d. **levels of organization-** There are 5 levels of organization a. b. c. d. e. i. **Homeostasis-** cells in a multicellular organism a. b. c. **negative feedback-** Opposes an initial change and is widely used to maintain homeostasis a. **positive feedback -** Output enhances or amplifies a change so that the controlled variable continues to move in the direction of the initial change a. b. **Pathophysiology -** abnormal functioning of the body associated with disease **\ [Mon. Nov. 11 Nervous System I]\ Nerve vs neuron-** Neurons are the basic units of the nervous system that transmits nerves. Nerves are the bundles of neurons that create nerve impulses and nerve nets **Cephalization-** Concentrating sensory organs and nervous system components at the front of the body a. i. ii. **PNS -** Movements or the actions from an effector **CNS-** Controls the brain and spinal cord **sensory neuron -** Nerve cells that are activated by sensory input from the environment **Interneuron -** Projects information from sensory neurons to motor neurons **motor neuron -** Neuronal cells located in the central nervous system (CNS) controlling a variety of downstream targets **Dendrite -** Receive messages from other neurons and the environment, and carry those signals to the cell body of a neuron **axon hillock -** A specialized part of cell body (soma) of a neuron that connects to the axon **Axon -** Electrical impulses from the neuron travel away to be received by other neurons **postsynaptic and presynaptic cell -** A presynaptic neuron transmits the signal toward a synapse, whereas a postsynaptic neuron transmits the signal away from the synapse **Synapse -** A structure that allows a neuron (or nerve cell) to pass an electrical or chemical signal to another neuron or a target effector cell **Neurotransmitter -** Molecules used by the nervous system to transmit messages between neurons, or from neurons to muscles **membrane potential -** Difference in electric potential between the interior and the exterior of a biological cell **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 **resting potential -** The electrical potential difference across the plasma membrane when the cell is in a non-excited state; stays at -70 mV for resting potential **threshold potential -** Membrane potential must be depolarized to initiate an action potential **Depolarization -** A process that shifts the electrical charge distribution within a cell, making it less negatively charged compared to its environment **Repolarization -** The recovery of the membrane potential from a state more positive than the resting potential back to the original resting potential **Voltage-gated Na,K, & Ca channels -** Act as monitors inside the cell to allow molecules inside the cell to get the correct electrical membrane potential **inactivation gate -** A protein structure that closes to stop the flow of sodium ions through a voltage-gated sodium channel **Na/K pump -** Maintains the concentration of sodium and potassium ions inside and outside of cells **Na & K ion channels (leaky)-** They are always open or \"leaking\" a small background current to regulate the resting membrane potential of a neuron **hyperpolarization/refractory period-** Neurons naturally become hyperpolarized at the end of an action potential **glial cell -** Any of the cells that hold nerve cells in place and help them work the way they should **Node of Ranvier-** Gaps in the myelin sheath that allow electrical signals to travel quickly down the axon of a neuron **Saltatory propagation -** Action potentials along myelinated axons from one node of Ranvier to the next, increasing the conduction velocity of action potentials **axon terminal-** The ends of axons which transmit messages to other cells via use of neurotransmitters at synapses **(neurotransmitter storage) vesicles -** Store various neurotransmitters that are released at the synapses **ligand-gated ion channel -** Protein channel receptor complex with a binding site for a small molecule. They open their permeability to certain ions in response to a ligand. **synapse (synaptic cleft) -** a small gap between the axon terminal of the presynaptic neuron and the membrane of the postsynaptic cell **pre & postsynaptic membrane -** The presynaptic terminal is at the end of an axon and is the place where the electrical signal (the action potential) is converted into a chemical signal (neurotransmitter release); The postsynaptic terminal membrane contains specialized receptors. **[Wed. Nov. 13 Nervous System II]\ Signal transduction pathway -** a series of molecular interactions triggered by the binding of a signaling molecule to its receptor, leading to the activation of various intracellular pathways involved in cell signaling **Myelin sheath -** an insulating layer, or sheath that forms around nerves, including those in the brain and spinal cord **EPSP & IPSP (literally means Excitatory/Inhibitory PostSynaptic Potential but we'll call them EPSP and IPSP) -** EPSPs can also result from a decrease in outgoing positive charges, while IPSPs are sometimes caused by an increase in positive charge outflow **Temporal vs Spatial summation -** Temporal summation is multiple EPSPs arrive quickly at a single synapse and set off an action potential; while spatial summation are EPSPs at two or more different synapses set off an action potential **afferent vs efferent neurons-** Afferent neurons are sensory neurons that carry nerve impulses from sensory stimuli towards the CNS and brain, while efferent neurons are motor neurons that carry neural impulses away from the CNS and towards muscles to cause movement **Somatic responses** - Contain all voluntary movements; conscious reactions, sensing and responding to the environment, sight, smell, sound, etc., and motor neurons that excite muscles causing contractions **Autonomic responses -** Contain involuntary responses; unconscious reactions, as well as regulating internal body functions that maintain homeostasis - parasympathetic and sympathetic **Sympathetic -** Functions with the autonomic nervous system; **Parasympathetic -** **Motor endplate -** A specialized area of a muscle fiber where a nerve terminal and muscle tissue meet and communicate **Acetylcholine -** A neurotransmitter that plays a role in memory, learning, attention, arousal and involuntary muscle movement **reciprocal inhibition (in a reflex circuit) -** The spinal cord process of inhibition of motor neuron pool when the antagonist motor neuron pool is activated; in reflex circuit it follows these steps : a. b. c. d. e. **[Fri. Nov. 15 Sensory Systems I]\ Sensory receptor cell-** Extra special protein in sensory cells that are embedded in sensory organs **sensory organ -** An organ that needs specified sensory cells; photoreceptor cells within the eye are an example **sensory transduction -** Energy transformation from external world to internal world **Chemoreceptor -** Receptors for smell and taste that generate neural signals on binding with particular chemicals in their environment ; a molecule binding to a protein receptor which sends signal to ion channel to open allowing sodium (Na+) into the cell making it depolarized **Mechanoreceptor -** When pressure is added to thin skin such as cuticle skin, the ion channel opens allowing ions into the cell making it depolarized **Photoreceptor-** Light entering the protein receptor which signals the ion channel to close making the cell hyperpolarized **Electroreceptor -** **Thermoreceptor -** **Nociceptor -** **lateral inhibition -** Cell interaction where a nearby cell adopts inhibitory patterns; lateral inhibition of sensory receptors cells enhances edge and border detection by reducing excitation of adjacent interneurons **G-protein coupled receptor (GPCR) -** Group of proteins in cell membrane that receive signals from outside the cell and transmit them inside - 1. Extracellular messenger binds to receptor which actives the messenger pathway **G-protein -** Proteins that act as a molecular switch inside the cell and are involved transmitting signals from a variety of stimuli outside a cell to inside **Olfactory epithelium -** Section within the olfactory nerves where the olfactory sensory neurons sit (between the axon and chemo-sensitive hair) **olfactory sensory neuron -** Neuron within the Olfactory epithelium that sense odorants and bind to specific receptors on the chemosensitive hairs that project into the nares (nostrils) **chemo-sensitive hair -** Inside the mucus layer of the olfactory nerves **taste bud -** Contain taste receptor cells that are packaged with supporting cells in an arrangement like slices of an orange **taste sensory cell -** A "slice" of so called orange above **Microvilli -** Thin membrane "bumps" that are found near the surface of cell types **5 flavors (which are G-protein coupled?) -** The 5 basic flavors of tastes are: a. b. c. d. e. **trigeminal nerve -** **[Mon. Nov. 18 Sensory Systems II]\ Stereocilia -** **mechanoreceptor hair cell -** **support cell -** **vestibular system -** **semicircular canal -** **Outer -** **middle (malleus, incus, and stapes) -** **inner ear -** **Vestibulocochlear Nerve (both branches) -** **Cochlea -** **Eardrum -** **basilar membrane -** **tectorial membrane -** **organ of Corti -** **hair cell stereocilia -** **Retinal -** **Opsin -** **Fovea -** **Retina -** **Lens-** **ciliary muscle-** **Iris -** **optic nerve -** **rod vs cone -** **discs (containing conopsin or rhodopsin) -** **phototransduction cascade -** **bipolar cell (both on and off versions) -** **ganglion cell -** **horizontal cell -** **amacrine cell -** **graded potential -** **[Wed. Nov. 20 cont. on Fri. Nov 22 Sensory Systems III\ ]Forebrain -** Composed of the cerebral cortex, thalamus, and hypothalamus **Midbrain -** Contains or is part of the brain stem **Hindbrain -** Composed of pons and medulla (which make up the brainstem) as well as the cerebellum **Cerebellum -** The cerebral cortex; contains the outer layer - "grey matter" neutral soma, as well as the inner layer white matter neuronal axons; integrates motor and sensory information allowing for complex motor tasks **medulla oblongata -** Center for respiration and circulation helps regulate breathing, heart and blood vessel function, digestion, sneezing, vomiting, and swallowing **Hippocampus (and amygdala)-** Controls behavior, instincts, emotions, and motivation, spation orientation and navigation, learning and LTM formation, as well as neurogenesis **Cerebrum-** Contains all lobes of the brain - brain is composed of cerebrum, cerebellum, and brainstem **basal nuclei (basal ganglia) -** Consist of several masses of grey matter located deep within the cerebral white matter; plays an important role in motor control by inhibiting muscle tone, maintaining purposeful motor activity, suppressing useless or unwanted movement, and motoring or coordinating slow, sustained contractions **Thalamus -** Relays info to the cortex but also regulates consciousness; sensory "relay station" and is important in motor control - "relay station" for preliminary processing of sensory input **white vs. grey matter -** White matter is the lighter parts of the brain surrounded by grey matter which are the darker parts around the outside or grooves **Frontal lobe-** Controls decision making, taste, and smell **Parietal lobe -** Responsible for body/spatial awareness **Occipital lobe -** Processes visual information **Temporal lobe -** Processes sound and speech **cortices for vision -** **Smell -** **Taste -** **Hearing -** **primary motor cortex -** Responsible for basic skeletal muscle movement in response to PSC - area touching primary somatosensory cortex **primary somatosensory cortex -** Human body sensory - takes in tactile info such as vibrations, pain, temperature, and position - area touching primary motor cortex **Dopamine -** Depression involves abnormal levels of this neurotransmitter **Serotonin -** Depression involves abnormal levels of this neurotransmitter **Cognition -** **synaptic plasticity -** Repeated stimulation induces new dendritic synapses to grow further strengthening the signal connection between the two cells thereby reinforcing a memory **long-term potentiation -** Repeated release of the neurotransmitter glutamate stimulates the production of new glutamate receptors, increasing the strength of the signals received by the cell **Electroencephalogram (EEG) -** A record of postsynaptic activity in cortical neurons - detects brain activity by measuring electrical impulses which are associated with different wavelengths (include beta, alpha, theta, and delta) **Sleep -** Stages of sleep a. b. c. i. ii. iii. iv. 1. 2. **[Mon. Nov. 25 Muscles]\ striated vs smooth muscle -** Striated is made of skeletal and cardiac muscle whereas Unstriated is strictly just smooth muscle - made of smooth muscle cells, a cell nuclei, and is an involuntary muscle **skeletal vs. cardiac muscle -** Skeletal muscle are composed of muscle fiber (skeletal muscle cell) with multiple nuclei - as well as a voluntary movement (somatic NS control), whereas cardiac muscle is composed of cardiac muscle cells containing cell nucleus and intercalated discs - as well as an involuntary muscle (autonomic NS control) **muscle bundle -** Muscle cells grouped together in a bundle which group to form a "muscle" **muscle fiber (cell) -** Elongated cells that are embedded in surrounding connective tissue **Myofibril -** Bundles of protein filaments **thick vs. thin filaments -** Actin is thin filaments that are composed of actin molecule wrapped in tropomyosin; Thick filaments made of myosin in a bundle with globular heads coming out **Troponin -** A protein that\'s found in the cells of your heart muscle **Tropomyosin -** The guard mechanism that prevents a skeletal muscle from contracting irregularly or on its own **Sarcomere -** The basic contractile unit of muscle fiber **Z-disc -** Marks the boundaries of sarcomeres, the contractile units of striated muscle cells **Titin -** Providing elasticity to sarcomeres **I band -** Composed of only actin, light colored and sits as a cross in the middle of the Z-line; it's length contracts or shortens during muscle contraction **A band -** Composed of myosin and actin in an overlapping pattern, dark colored, contains the H-band in the middle (Hensons' zone); it's length remains unchanged during contraction **sliding filament model -** The sliding of actin past myosin generates muscle tension **cross-bridge cycle -** Also known as rowing the boat a. b. c. d. **T-tubule -** **sarcoplasmic reticulum -** **antagonistic muscles -** Muscle pair as one muscle contracts the other muscle relaxes or lengthens; i.e. the biceps shorten to flex the elbow joints while the receipt shortens to extend the elbow joint **extension vs. flexion -** Flexion is the strengthening or use of the bicep while extension is the strengthening of a joint by making joint motions **twitch vs. tetanic contraction -** Each stimulus causes a twitch; Muscle force sums to higher levels when action potentials stimulate the muscle at higher rates, reaching a tetanus **force summation -** The muscle fibers are activated by the next action potential before they have had time to completely relax **motor unit -** A motor neuron and all the muscle fibers it controls **[Wed. Nov. 27 Endocrine]\ Intracrine vs Endocrine vs Paracrine vs Autocrine vs Exocrine (pheromones) -** **hydrophilic vs. hydrophobic hormones -** **peptide/amine hormones -** Hydrophilic - more abundant, do not cross lipid bilayer, activate signal transduction pathways, responses occur more quickly and effects last for hours **steroid hormones -** 2 classes : corticosteroids and sex steroids, cross the lipid bilayer, alter gene expression and proteins produces, response is slower, and effects last days or months **Hypothalamus -** links nervous system and endocrine via the pituitary gland; regulates many homeostatic functions - collection of specific nuclei and associated fibers that lie beneath the thalamus, integrating center for many important homeostatic functions **anterior pituitary -** Responsible for hormone secretion by thyroid, adrenal cortex and gonads, and growth **posterior pituitary -** Responsible for water balance, and salt balance **neurosecretory cells -** A specialized neuron that produces chemical messengers that are released into the bloodstream and affect target tissues **releasing factor hormones -** Peptide hormones which are reproduced by the hypothalamus and transferred to the portal veins **tropic hormones -** Stimulate other endocrine glands; (FLAT) - follicle stimulating hormone, luteinizing hormone, adrenocorticotropic hormone, thyroid stimulating hormone **direct hormones -** Directly affects; (PEG) - prolactin stimulating lactation, endorphins (made in pit and everywhere), and growth hormone **vasopressin (ADH) -** **Insulin -** **Glucagon -** **glucose & glycogen -** **positive feedback -** **adrenal cortex -** **epinephrine and norepinephrine -** **[Mon. Dec. 2 Respiration]\ Gas exchange -** **bulk flow vs diffusion -** **Ventilation -** **Circulation -** **blood (RBC) -** **tidal ventilation -** **intercostal muscles and diaphragm -** **Trachea -** **Lungs -** **Bronchi -** **Bronchiole -** **Alveoli -** **pulmonary capillaries -** **Hemoglobin vs Myoglobin -** **Heme group (Fe) -** **02 dissociation curve -** **cooperative binding -** **[Wed. Dec. 4 Circulation and the Heart]\ Artery -** Contains more oxygenated blood and moves it away from the heart; moves in low volvumes and high pressure **arteriole -** Small blood vessel that branches off from artery linked to capillaries **vein -** Contains deoxygenated blood and moves it towards the heart; moves in high volume with lower pressure - contains valves to allow pressure to move blood towards the heart **venule -** Smallest veins and receive blood from capillaries **Capillary -** Delicate blood vessels throughout the body that brings nutrients and oxygen into cells and organs **pressure vs resistance -** Pressure is the force blood circulates against arteries whereas resistance is the pushback against blood in the circulatory system **blood pressure vs. osmotic pressure -** **Lymph -** Fluids that are squeezed out of cells such as water, proteins, or minerals that are reabsorbed through this **vasoconstriction vs vasodilation -** Vasodilation occurs when the vessels of blood get wider and vasoconstriction is the constriction of blood vessels **pulmonary vs systemic circulation -** The pulmonary circulation is a short loop from the heart to the lungs and back again. The systemic circulation carries blood from the heart to all the other parts of the body and back again **Every term on the heart diagram -**  **systole -** The contraction of a chamber in the heart causing the ejection of blood out of the heart - the ventricles contract pumping blood out of heart **diastole -** The relaxation of the chamber in the heart allowing the chamber to fill with blood - the atria contracts filling the ventricles with blood **SA node -** Generates electrical signals that causes the upper chambers in heart to contract (pacemakers) **AV node -** Generates impulses for contraction of heart to ensure coordinated blood flow through chambers **modified muscle fibers -** Regulate and coordinate the pumping action of heart **electrocardiogram (EKG) -** The sympathetic stimulation which speeds up the heart rate while the parasympathetic stimulation slows the heart down - EKG shows this and the nodes that activate and contract allowing for the repolarization of ventricles **[Fri. Dec. 6 Ingestion, Digestion, and Absorption]\ Essential amino acids (don't memorize them) -** Include : isoleucine, Leucine, Lysine, Methionine, Phenylalanine, Threonine, Tryptophan, Valine **vitamins and minerals (don't memorize them) -** Vit. A, Vit B 1-9+12, Vit. C, Vit D, Vit. E, and Vit. K **foregut -** Contains the mouth, esophagus, and stomach **midgut -** Contains the small intestine **hindgut -** Contains the large intestine **mechanical -** Physical mixing and churning that breakdown large masses of food into smaller masses of food **chemical digestion -** Using enzymes to break bonds of large molecules (polymers) into small molecules (monomers) **Ingestion -** Process of taking substance into body by swallowing it allowing it to move to other process of digestion **Digestion -** Process of preparing food for absorption, breaking down to increase surface area, mixing the food up, and moving it along the digestive tract **Absorption -** The process of taking in the nutrients and chemicals from the food into the body **Expulsion -** The process of allowing the broken down food out of the body **Mouth -** Where the digestive process begins, and food/substance is taken into the body; Contains teeth to allow for the mechanical digestion of food to make for an easy swallow **Saliva -** Watery liquid from the salivary glands released into mouth that make substance moist and easy to swallow **Amylase -** Enzyme for carbohydrate digestion **Esophagus -** The hollow, muscular tube that passes food and liquid from your throat to your stomach **Peristalsis -** The rhythmic muscular contraction and relaxation that moves food downward; occurs throughout the GI tract **Stomach -** The stomach contains enzymes that keep its pH down, as well as cells that line the stomach that secrete to allow for low pH; breaks down chemicals and stores food as well as digests **Gastrin -** Secreted when food arrives in the stomach to stimulate production of HCL and pepsinogen; 3 types of exocrine cells found that contribute to the gastric juices a. b. c. **Pepsin -** Breaks down proteins into amino acids **Pepsinogen -** Turns into Pepsin through the activation for protein digestion **HCl -** Has four main functions a. b. c. d. **Lipases -** **parietal cell -** **pyloric sphincter -** **small intestine -** **Duodenum -** Fats in the duodenum stimulate cells lining the duodenum to secrete CCK that turns stimulates the gallbladder to contract and release stored bile that helps to break down fats - the first part of the small intestine connected to the stomach **Pancreas -** Contains ducts that enter the duodenum that secretes necessary digestive products - outside of the digestive tract **CCK -** **gallbladder -** Stores bile when not being secreted **bile (or bile salts) -** Help with the digestion of fats **Secretin -** Digestive hormone secreted by the duodenum that regulated gastric acid secretion and pH levels in the duodenum **HCO3-** Bicarbonate; byproduct of body's metabolism **pancreatic duct -** A duct that joins the pancreas to the bile duct - supplies pancreatic juices from exocrine pancreas **villi -** The folds form numerous tiny projections which stick into the open space inside small intestine and covered with cells to help absorb nutrients **microvilli -** The cells on the billi are packed full of tiny hairlike structures **Na-glucose cotransporter -** Allows sodium and glucose to transport across cell membrane **glucose transport protein -** Membrane proteins that facilitate the transport of glucose across the plasma membrane **hepatic portal vein -** Blood vessel that carries blood to the liver from the intestines, spleen, pancreas, and gallbladder **Liver -** Performs many functions and secretes bile - fluids, waste, and other molecules are found here **large intestine (colon) -** Digestion and absorption processes are mostly complete by the time the chyme reaches the large intestine - Colon absorbs water and salt, and propels waste forward for removal **Rectum -** The last several inches of the large intestine closest to the anus **Cellulose -** Fiber that helps with digestion, weight management, etc. **Cellulase -** Enzyme used to degrade cellulose **Acinar -** Highly polarized epithelial cells containing microvilli **[Mon. Dec. 9 Digestion II]\ (no new terms)** **[Wed. Dec. 11 Osmoregulation]\ Osmosis -** The process of which a selectively permeable membrane allows movement of water but not solutes - water moves by osmosis from a region of lower to high solute concentration **osmotic pressure -** The amount of force applied to a solute that prevents solvent from moving across membrane **Osmoregulation -** The active regulation of osmotic pressure of an organism's body fluids detected by osmoreceptors to maintain homeostasis in organisms water content **ammonia vs urea vs uric acid -** Ammonia is the excretion of nitrogenous waste out of aquatic animals that is very toxic but easily released; Urea is the excretion of nitrogenous waste of mammals, which is extremely energetically costly to produce; Uric acid is the nitrogenous waste of birds, insects, small animals **the processes of filtration, reabsorption, and secretion -** The process is a. b. c. **Nephron -** Small section of the kidney contains the glomerular filtrate, collecting duct, and tubule **renal cortex vs renal medulla -** The renal cortex surrounds the inside of the organ which is considered the medulla **Glomerulus -** The main filtering unit of the kidney **Bowman's capsule -** Part of the nephron that forms a cup-like sack surrounding the glomerulus **Podocyte-** Cells in the bowman's capsule in the kidneys that wrap around capillaries of the glomerulus **proximal tubule -** Reabsorption of filtrate in accordance with the needs of homeostasis **distal convoluted tubule -** regulation of water electrolytes, and hydrogen-ion balance **loop of Henle (ascending vs descending limbs) -** Responsible for the reabsorption of water and making the medulla hypertonic a. i. ii. b. iii. iv. **collecting duct -** Part of the loop of henle that collects urine from the nephrons and moves it to the renal system and ureters **Ureter -** The duct which urine passes from kidney to the bladder **urea recycling -** A process in kidneys that involves the reabsorption and secretion of urea several times **antidiuretic hormone (vasopressin) -** Secreted in response to an increase of plasma osmolality or decrease in plasma volume **Aquaporin -** Water channels in cell membranes facilitating the movement of water and other small molecules across the cell