Cell Biology: Terms and Definitions, Quizzes of Biology

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TERM 1 molecules DEFINITION 1 assembles of atoms major physiological ones= proteins, carbs, lipids, and nucleic acids TERM 2 cells DEFINITION 2 -basic unit of life - movement, reproduction - well defined perimeter - uses energy, has metabolism ( ex: rbc) - removes waste ( CO2, lactic acid, H+) TERM 3 Tissues DEFINITION 3 - collection of similar cells with same local function - term also used generally as "lung tissue" - typically stay in one place TERM 4 organs DEFINITION 4 group of tissues ( different ones work together) that perform a distinct function in body TERM 5 Systems DEFINITION 5 - collection of organs - control major coordinated functions; respiration, circulation TERM 6 Homeostasis DEFINITION 6 - maintains the normal physiological state to things you can not live without stay healthy TERM 7 Internal environment DEFINITION 7 - interstitial fluid - body tries to maintain this -liquid around cells and easy communication TERM 8 Negative Feedback DEFINITION 8 - common - event causes a change away from set point and causes you to return to where you started -ex: BP, Ion concentrations, muscle reflexes - basis of homeostasis TERM 9 Positive Feedback DEFINITION 9 - rare but important - event x causes a change to a new set point ( state change) - no return to original set point -ex: blood clotting, parturition ( child birth) TERM 10 Cytosol DEFINITION 10 - liquid (water base) portion of space between nucleus and plasma membrane - high protein content TERM 21 Lysosomes DEFINITION 21 - contain digestive enzymes (acid hyrolases) - merge with endocytotic vesicles - digest molecules down to usable size - ex: protein= amino acid, complex carbs= monosaccharides TERM 22 peroxisomes DEFINITION 22 - contains anti- oxidants ( vit C and vit E also does this outside cells) - destroys oxygen( odd number electrons) radicals (very reactive, destroy protein function) - TERM 23 ATP DEFINITION 23 adenosine tri phosphate - cellular money - highly transferable energy TERM 24 Anaerobic Energy Production- Glycolysis DEFINITION 24 - no oxygen - in cytoplasm (Free ATP) and cell membrane (ATP for ion pumps) - 2 ATP/ glucose without oxygen - Glucose, NAD, 2 ATP over 10 reactions make NADH, pyruvate, 2ATP - NADH, pyruvate make NAD and lactate ( recycle NAD) TERM 25 Mitochondria Aerobic Energy Production DEFINITION 25 - with oxygen - double membrane structure - outer membrane has large pores - TCA cycle inside matrix of inner membrane - electron transport system part of the inner membrane uses oxygen - pyruvate transported to mitochondria -fats only digestive when using oxygen TERM 26 citric acid cycle DEFINITION 26 aka krebs cycle, TCA, - in mitochondria matrix- 7 reactions - pyruvate, NAD, FAD make CO2, ATP, NADH, and FADH2 TERM 27 mitochondrial inner membrane DEFINITION 27 - forms internal compartments known as cristae, which allow greater space for the proteins such as cytochromes to function properly and efficiently. - cytochromes from electron transport system on inner membrane TERM 28 oxidative phosphorylation DEFINITION 28 - NADH donates electron to ETS, H+ follows, NAD recycled - Electron passes,ATP made at 3 cytochromes - electron and H+ and oxygen make H2) use of inhaled oxygen - 3 ATP/ NADH, 2 ATP/FADH2, 34 ATP/glucose TERM 29 Vaults DEFINITION 29 - octagonal barrel shaped structures - may be involved in transport form nucleus to cytoplasm - mRNA and ribosomes are possible cargo TERM 30 cytoskeleton DEFINITION 30 - intracellular frameworks - protein polymer filaments of different size and functions TERM 31 microtubules DEFINITION 31 - polymers of tubulin, have positive and negative ends, cell stability/transport along neurons, more vesicles, organelles and chromosomes -movement: kinesin carries cargo along microtubules in positive direction, dynein moves cargo in negative direction - taxol ( anti cancer drug) binds to and stabilizes microtubules, kills dividing cells TERM 32 cilia DEFINITION 32 - sweep things forward -ex: in lung, oviducts - dynein drives microtubules twists, propels muscus, ovum - looks like field of wavy wheat TERM 33 Flagella DEFINITION 33 - propel sperm into ovum - rotary movement -tail like projection that protrudes from cell body TERM 34 intermediate filaments DEFINITION 34 - permanent load bearing filaments in stressed cells ( skin) - maintain shape TERM 35 Microfilaments DEFINITION 35 - thinest filament of cytoskeleton and found in cytoplasm - thin filaments- actin polymer - thick filaments- myosin - movement in muscle and WBC's TERM 46 carbohydrate- protein complexes DEFINITION 46 - identify self to immune system - basis for seperation of cells into tissues during embryonic development - limit normal tissue growth to confined region - abnormalities occur during metastatic cancer TERM 47 CAMs- cell adhesion molecules DEFINITION 47 - proteins - anchorcells - control cell migration TERM 48 Tight junctions DEFINITION 48 - block movement between cells - create tissue sidedness - skin, intestines, kidneys - allow selective transport, molecules must go through cells TERM 49 desmosomes DEFINITION 49 - cellulare equivalent of rivets - hold moving cells together: skin, heart TERM 50 gap junction DEFINITION 50 double sided channels - channels between cells- ion pass; electrical link - electrical signal from one cell activates next cell - heart, GI tract, bladder, uterus TERM 51 diffusion across membrane DEFINITION 51 - drivin by chemical or electrical gradients simple diffusion channels and carries - diffusion goes in all direction: net diffusion will always go from high to low (spread) TERM 52 Hydrophobicity DEFINITION 52 - fats and gases cross easily - fluidity allows micro RBC's to deform through 7 micron capillaries, enhances oxygen transport - pump entire blood supply every minute - capillaries are small for blood cells so O2 can go through both cell walls without passing plasma TERM 53 Fick's Law of diffusion DEFINITION 53 - rate of diffusion Q Q= (P)(A) (deltaC/delta X)/ (MW) p= permeability, hyrophobicity, hydrophilicity a=area delta c/ delta x = concentration gradient mw=molecular weight (size) TERM 54 Ion Channels DEFINITION 54 - different types for different ions - allow ions to move by chemical/ electrical gradients TERM 55 osmosis DEFINITION 55 - diffusion of water - water moves from high concentration ( low solute concentration) to low water concentration ( high solute) - semi-permeable membranes allow water to cross, but nothing else TERM 56 carrier transport DEFINITION 56 - protein molecules change shape in membrane and more molecules across - energy for transport may come from concentration gradient or from ATP TERM 57 specificity DEFINITION 57 - each carrier transports a specific molecule or type of moelcule TERM 58 saturation DEFINITION 58 - there are only limited + of carries in each cell - wen all carriers are being used, the rate will be at a max - transport max ( TM) limits carrier mediated transport TERM 59 facilitated diffusion DEFINITION 59 - no ATP used, move down diffusion gradient - molecules bind to one side, carrier reorients, molecules leave on opposite side-more binding on high concentration side - movement from high to low concentration TERM 60 active transport DEFINITION 60 - used ATP for energy to move ions against concentration gradient - movement from low to high - Active transport produces the ion gradients across cell membranes TERM 71 resting MP changes DEFINITION 71 - membrane potential will change in many cells, including nerve and muscle cells - mp always is negatie at rest - mp magnitude decreases ( goes toward 0) during depolarization - mp goes up ( gets more neg) during hyperpolazation TERM 72 depolarization DEFINITION 72 - membrane potentioal less negative ( -70 to -60) - caused by k+ channels closing, Na+ channels opening - never gets to +60 most is +20 TERM 73 hyperpolarization DEFINITION 73 - mp gets more negative ( -70 to -80) - caused by K+ channels opening, na+ channels closing - mp moves toward k+ equilibruim potential - never gets to - 90, lowest -85 TERM 74 graded potentials DEFINITION 74 - triggered by agonist or by physcial force - ex: receptor potentials, local potentials - size- proportional to size of stimulus - spreads to adjacent areas, nut decays rapidly over time and distance - small stimulus will open up few and large cells stimulus open many ion channels - in neurons, muscles, gps needed to reach threshold of action potential TERM 75 action potential DEFINITION 75 - electrical signal, long range in neurons and muscle - activated by graded potential - action potential's do not degrade over time and distance - only one direction - will always look same; send by frequency TERM 76 voltage- gated channels DEFINITION 76 - will open when membrane reaches particular voltage - usually +50 to 20 mv above resting potential - all v-gated channels open together, causing action potential - enter in activated state soon after opening, making refractory period TERM 77 phases of AP DEFINITION 77 - controlled by different open channels - voltage - gated sodium channels only open for short amount of time then are stuck closed for a while- thats why some people can run faster TERM 78 depolarization to threshold DEFINITION 78 firing level (1) - chemical or mechanical- gated na+ channels open - na+ enters down gradient - t= threshold- 15-20 - at T all v-gated na+ channels open - TTX blocks fast v-gated na+ channels TERM 79 AP Spike DEFINITION 79 2 - since all v-gated Na+ channels open together, all AP's in one neuron are identical - na_ enters, rapid depolarization to +20 mv - doesnt reach Na+ equilibrium potential becasue some v gated k+ channels also open TERM 80 re-polarization DEFINITION 80 3 - v-gated na+ channels close after 1-2 msec - k+ channels still open, K+ leaves, membrane potential falls TERM 81 hyperpolarization DEFINITION 81 4 - voltage goes below resting because extra K+ channels are still open - never to -90 mv ( k+ equilibruim potential) than at rest TERM 82 return to resting potential DEFINITION 82 5 - extra K+ channels close TERM 83 neural structure DEFINITION 83 - receive and pass on signals TERM 84 dendrites DEFINITION 84 - receive neurotransmitter from other neurons - many branches - no action potential here, only graded potentials TERM 85 excitatory Postsynaptic potentials- EPSPs DEFINITION 85 - NT binds and Na+ channels open - na+ enters and causes depolarization - one EPSP is not enough to reach threshold TERM 96 Neurotransmitters DEFINITION 96 - specific, each neuron has only one type of NT - variable neural cell length- NTs work locally as released - NTs released by exocytosis- synapse cell to cell - neural to neural, muscle, endocrine cells - rapid removal diffusion, digestion, reuptake TERM 97 endocrine DEFINITION 97 - hormones released from endocrine tissue (endothelial origin) - broad effects- hormone released into blood -goes everywhere - effect depends on target cell receptor TERM 98 neurohormones DEFINITION 98 - released from neurons into the blood - functions as other hormones- receptor dependent TERM 99 hydrophilic hormones DEFINITION 99 - cannot cross the membrane, rely on membrane receptor activation, - membrane proteins produce second messengers TERM 100 hydrophobic hormones DEFINITION 100 - diffuse easily into cells - need transport molecules in watery environments TERM 101 steroids thyroid hormone DEFINITION 101 - vit a, vit d increase protein synthesis by activating genes wide- spread actions, significant side effects TERM 102 second messengers DEFINITION 102 Second messengers are molecules that relay signals from receptors on the cell surface to target molecules inside the cell, in the cytoplasm or nucleus. - made at membrane - internal activation by hydrophilic hormone (1st essenger) - only cells with receptors respond TERM 103 cAMP DEFINITION 103 - ATP- cAMP- activate kinases, add phosphate to molecules - kinases cascades amplify signals - indiividualized effects in different cells TERM 104 cGMP DEFINITION 104 - GTP- cGMP activates kinase TERM 105 IP3 DEFINITION 105 - causes release of intracellular ca++ stores - ca++ stored in sarcoplasmic reticulum a structure modified from endoplasmic TERM 106 Nuclear receptors DEFINITION 106 -Form interface between hydrophobic hormones and genes - Will determine which genes activated by hydrophobic hormones -Variations in gene activation in different cells basis for side effects TERM 107 calcium DEFINITION 107 -Released from intercellular sarcoplasmic reticulum - Enter across cell membrane through Ca++ channels (by IP3s) - Binds to and alters protein activity - Cell-to-cell Ca++ sign produces coordinated cilia waves exocytosis - Gap Junctions- depolarization causes muscle contraction adjacent cells by opening ca++ channels TERM 108 G Proteins DEFINITION 108 - Timing proteins - Bind GTP increases activity until GTP GDP - Regulate vesicle movement , cytoskeleton, growth , vision, 2nd messenger TERM 109 Neural- Endocrine Comparisons DEFINITION 109 - Neurons coordinate rapid, precise, brief response - electrical activity covers most distance, neurotransmitter diffusion distance is small - hormones control long duration activity, slower responses - More complex reactions, long duration binding of hormones TERM 110 afferent neurons DEFINITION 110 - afferent neurons cary info into the CNS - both conscious and unconscious info is carried TERM 121 nutrition DEFINITION 121 - needs a constant supply of glucose and oxygen to survive - no glucose storage needs constant blood supply - stroke reduces blood flow, vessel blockage or breakage TERM 122 cortex DEFINITION 122 -upper part of brain- cerebrum - heavily rigid, 80% of brain - unique human qualities reside here - voluntary movement, conscious thought, language, morals TERM 123 frontal lobe DEFINITION 123 - movement control, personality, descisions, moral judgement TERM 124 parietal lobe DEFINITION 124 - somesthetic (touch) perception and proprioception ( position) TERM 125 occipital lobe DEFINITION 125 - visual integration TERM 126 temporal lobe DEFINITION 126 - hearing and emotion - long term memory TERM 127 plasticity DEFINITION 127 - no mitosis of neurons but learning involves making new synapse between existing neurons -practiced motor activity enlarges controlling area of brain - area grows larger, more neurons involved - if cortical input reduced, areas received input form adjacent areas - if cortical area is damaged, adjacent areas can sometimes pick up lost function TERM 128 language control DEFINITION 128 - connection of sounds and symbols with objects TERM 129 brocas area DEFINITION 129 - in frontal lobe - speech formation deficit - difficulty forming words spoken or written TERM 130 wernicke area DEFINITION 130 -temporal lobe - comprehension of auditory/ visual info deficit can form sound but they contain no content dont know what self is saying TERM 131 association areas DEFINITION 131 - higher brain functions associations cortexs integrate multiple inputs - prefrontal AC controls planning/ morals - parietal/ temporal/ occipital AC makes coordinated world view - links touch, sound, and sight TERM 132 hemispheres DEFINITION 132 - right side- visual, spatial relations- aesthetics - left side- analytical, processing and language - genius uses brain TERM 133 electroencephalogram DEFINITION 133 -background electrical activity of brain - recording on surface used for death determination - used to determine if someone is dead or alive