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flyboy248
on FreezingBlue Flashcards.
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Any substance that cannot be split into simpler compounds
Element
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How many elements occur naturally
96/112
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The Human body contains what and how many elements
- 26
- C, N, H, O = 96%
- K, Na, Cl, Mg, P, Ca, S, Fe- 3.8%
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Smallest unit of matter made up of subatomic particles arranged in a central core (nucleus)
Atom
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Number of protons in the nucleus
Atomic number
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Sum of protons and neutrons
Mass number
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Identical elements with different mass number
Isotopes
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An atom with a + or - charge because it has an unequeal number of p+ or e-
Ion
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The resulting combo of two or more atoms that share electrons
Molecules
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Substance that contain two or more different elements.
Compound
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Forces that hold together atoms of a molecule or compound
Chemical Bonds
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3 types of chemical bonds
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Process that involves energy change to provide that capacity to do work. In these, it occurs when new bonds form or old bonds break between atoms
Chemical reactions
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Chemical reaction in which more energy is released then absorbed (used)
Exergonic reaction
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Chemical reaction in which more energy is absorbed (used) then released.
Endergonic reaction
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Factors that promote a chemical reaction
- Conc of reactants
- Temp
- Catalysts
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4 types of chemical reactions
- Anabolic
- Catabolic
- Reversible
- Exchange
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Two or more molecules join together forming a larger and complex molecule (e.g. proteins)
Anabolic
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A large molecule is split into its individual components (ATP production by glucose catabolism)
Catabolic
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Are depenent on enzymes and concentration of reactants
Reversible
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Combination Reaction
Exchange
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Large molecules that carry out complex functions. Composed of a chain of C atoms to which an array of distinctive functional groups are attached.
Organic compounds
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Combination of small organic compounds called polymers (eg. glycogen- is a polymer of glucose units)
Macromolecules
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apolar amino acids
Leu, Iso,Val,Met,Pro,Tryp,Ty
Hydrophobic
-
polar amino acids
Asg, Asp, Cys, Glu, Ser, Thr, Arg, Lys, His
Hydrophylic
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Neutral amino acids
Ala, Gly
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Polymers of the 20 common amino acids joined together by a peptide bond. Human peptide bonds always occur at cis because this form is more stable. The amount of rotation of the bonds is restricted to the side chains (r groups) at either side of the peptide bond. In general, the more bulkier, the more restricted the rotation.
Proteins
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Represents the sequence of amino acids in a peptide chain including the disulfide bonds and post-translational changes.
Primary structure
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Represents the twisting and folding of the neighboring amino acids in the polypeptide chain. It is stabalized by hydrogen bonds -ex alpha helix
Secondary Structure
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Refers to the three dimensional shape of the polypeptide chain. It is supported by several types of bonds as disulfide bridges, hydrogen, ionic, and hydrophobic interaction
ex- B-pleated sheet
Tertiary Structure
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Arrangements of individual polypeptide bonds relative to one another.
Quaternary Structure
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Comprised of a nitrogenous base (purine or pyrimidine) a pentose sugar (rib or dexyrib) and a phosphate group. A specific sequence of purines and pyrimidines encode the genetic info of the human cell.
Nucleic Acids
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Levels of Complexity of Cells
Atomical, Molecular, Compound, Cellular, Tissues, Organs, Systems
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Characteristics of living organisms
Metabolism, Responsiveness, Movement, Growth, Differentiation, Reproduction
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Cell components
Plasma membrane, Cytosol, Organelles, Inclusions
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Composed of 75% phospholipids, 20% cholesterol, and 5% glycolipids
Lipid bilayer
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2 types of protein
Integral and Peripheral
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Amphipathic molecule with a hydrophillic phosphate head, and a hydrophobic fatty tail
Phospholipid
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An Amphipathic molecule
- works with cell adhesion, cell to cell recognition and communication, and regulation of growth and development.
Glycoproteins
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Membrane Protein Functions
- Channels
- Transporters
- Receptor
- Enzyme
- Cytoskeleton anchor
- Cell identity markers
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Selective permeability depends on:
- Lipid soluability
- Size
- Charge
- Channels or Transporters
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Passive process
- Depends on pressure or concentration differences and diffusion.
- 1- Simple diffusion
- 2- Osmosis
- 3- Bulk Flow
- 4- Facilitated Diffusion
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Process of random mixture of particles in a solution acheiving equilibrium Without Using Energy.
ex- O2, CO2, small COH, H2), lipid soluable
Simple Diffusion
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Factors hat influence diffusion
- Steepness of conc. gradient
- Temperature
- Mass of diffusion substance
- Surface area
- Diffusuon distance
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Diffusion of a solvent through a selective membrane. It is determined by the osmotic pressure (the pressure required to stop the net movement of pure water through a selective membrane)
Osmosis
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Movement of large volume of particles dissolved or carried in a medium (air flow, capillary blood flow)
Bulk Flow
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Movement of molecules through a selective membrane aided by specific membrane proteins that serve as channels or transporters (eg. glucose, vitamins, ions)
Facilitated Diffusion
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Saturation point
When all of the transporters are occupied, the maximum is reached.
Transport Maximum
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Energy spending process for the movement of a molecule against a concentration gradient.
Active process
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Movement of molecules across a selective membrane from a lower to a higher concentration area by pump proteins using energy released by splitting ATP
(eg. Ions, Na+, K+, Cl-, H+)
Primary Active Process
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Simultaneous movement of two substances, one of which is Na+ (supplies energy) against a concentration gradient maintained by a primary active transport.
Secondary Active Process
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Moves Na+ and a substance in the same direction across the membrane.
Symporters
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Moves Na+ and another substance in opposite directions across the membrane.
Antiporters
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Process through which small vesicles bud from a cell membrane to bring in or out material.
3 types: Endocytosis, Exocytosis, Transcytosis
Vesicular transport
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Phagocytosis (cell eating)
Pinocytosis (cell drinking)
Endocytosis
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Process for exporting substances from the cell
(eg. neurotransmitters, hormones, digestive enzymes)
Exocytosis
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eg. antibodies crossing the placenta
Transcytosis
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Gel like fluid in which the cells metabolic reactions occur. Contains suspended particles, minute filaments, and tubules
75-90% H2O
Proteins
Colloids
Lipids
Cytosol
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Specialized structures related with cell growth, repair, and maintenance.
Organelles
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Internal network of proteins inside the cytoplasm involved in locomotion, phagocytosis, and cell wall strength.
Cytoskeleton
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Rod like structure composed of actin filaments that provides support and movement assisting in cell shape.
Microfilament
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Largest of the cytoskeletal components. Cylindrical structure consists of tubulin. Major function is assembly of centromeres during cell division.
Microtubules
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Mainly composed of microtubules. Both structures are motile but only the flagella allows for locomotion.
Flagella and Cilia
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Largest Organelle. Is enclosed in a bi-layer membrane continuous with the ER. It harbors the genetic blueprints that directs cell division and production of proteins. Its nucleoli is involved in the production of rRNA.
Nucleous
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Membrane bound network of channels providing surface area for chemical reactions
Endoplasmic reticulum
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Related with synthesis of lipids and detoxification of drugs.
Smooth ER
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Synthesis for proteins to be exported
Rough ER
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Cytoplasmic site for protein translation and assembly. Some are free in the cytoplasm, while others are attached to the ER. 2 subunits Large 80's, and Small 30's
Ribosomes
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Membrane enclosed cisternae where proteins and lipids are packaged into secretory vesicles for export or insertion into the cell membrane.
Golgi complex
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Specialized vesicles which contain digestive enzymes for breakdown of nutrients and foreign bodies. Involved in Autophagy.
Lysosomes
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Specialized vesicles which contains enzymes for oxidation of organic substances.
Peroxysomes
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Cytoplasmic and nuclear organelle involved in the destruction of unneeded or damage proteins
Proteasomes
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Organelle in which energy is produced during cellular respiration.
Mitochondria
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Include normal endogenous compounds and storage of nutrients- ex lipofusin, melanin, glycogen
Cell inclusions
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An iron storage compound found within the cell. Is brown colored)
Hemosiderin
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Grandular yellow-brown pigmented granules composed of lipid-containing residues of lysosomal digestion.
Lipofuscin
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Sequence of events through which a cell undergoes complete division with a final product of two identical cells
Cell cycle
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Is the cell cycle similar in all cells?
No, it depends on the types of cells.. but it does have similar events.
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Cells which proceed through the cell cycle from one mitosis to the next proliferating throughout its life.
Continuously dividing (labile) cells
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Squamous cells
Surfaces of the skin, oral cavity, vagina, cervix
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Cuboidal epithelium
Ducts of endocrine and exocrine glands
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Columner epithelium
GI tract, Uterus, Fallopian tubes, Transitional epithelium of the urinary tract and the hematopoietic cell.
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Quiescent (stable) cells
Demonstrate low level of reproduction under adequate stimuli promotes rapid increase in cell division.
ex- Hepatocytes, pancreatic, kidney, endothelial and smooth muscle cells
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Nondividing (permanent) cells
- Cells which exited cell cycle at some point during intrauterine (fetal) development and will not undergo further mitotic division during post natal life
- ex- nerve cells, cardiac cells (myocytes) and to some extent the skeletal muscle cells.
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Somatic cells are in:
Mitosis
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Germ cells are in:
Meiosis
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What is the cell cycle composed of
- Duplication of genetic component (mitosis)
- Cytoplasmic division (cytokinesis)
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Cell cycle process- 3 phases
- Interphase
- Mitosis
- Citokinesis
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Phase between cell division
Interphase
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Cell engages in growth, metabolism, and production of substances required for division
(No chromosomal replication)
G1 phase
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Synthesis and replicayion of new DNA and associated proteins
S phase
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Cell engages in growth, metabolism, and production of substances required for division
-No chromosomal replication-
G2
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4 phases of Mitosis
- Prophase
- Metaphase
- Anaphase
- Telophase
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Prophase
- The longest phase
- Condensation of chromatin fibers becomes the chromosomes.
- The nucleoli disappears and the nuclear enveope break down.
- The mitotic spindle is formed developing three types of microtubules
- The mitotic spindle attaches to the chromosomes and distributes them to opposite poles
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3 types of microtubules formed by the mitotic spindle
- Nonkinetochore Microtubules
- Kinetochore Microtubules
- Aester Microtubules
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The centromeres line up in exact center of mitotic spindle (equatoral plane region)
Metaphase
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Anaphase
- The splitting and separation of centromeres and movement of sister chromatids toward opposite poles.
- The shortest phase
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Begins when chromosomal movement stops. The chromosomes begin to uncoil and two nuclear envelopes forms and the mitotic spindle breaks up.
Telophase
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Cytoplasmic division between the two daughter cells
Cytokinesis
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Karyotyping
- 1. Ability to stimulate cells into division by using mitogens (PHA)
- 2. Chemical agents that are toxic for mitotic spindle arresting cell division during mitosis
- 3. Use of hypotonic solutions
- 4. In vitro culture of human cells
- 5. Availability of different staining techniques
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Which cells may be used for karyotyping?
Any cells that may be promoted into division can be used.
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The most common cells or tissues used for karyotuping
- 1. Amniocytes (12-16 weeks in pregnancy)
- 2. Chorionic villi (earlier in pregnancy, when the mom hase undergone more then 2 spontaneous abortions)
- 3. Bone Marrow
- 4. Special studies for studying malignant processes
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Humans
- Have 46 chromosomes
- 22 Autosome (pairs) - alike in both sexes
- 1 pair of sex chromosomes
- XX = female
- XY= male
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Composed of 2 chromatids joined by a centromere or central are of condensation
P= short arm
Q = long arm
Chromosome
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How are human chromosomes identified
- By their characteristics in 8 groups A-H
- Sorted by:
- Size
- Location of centromere
- Presence of satelites
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When a chromosome is stained, a specific set of band patterns is observed
- G Banding (Giesma)
- Q Banding (Quinacrine) florescence microscopy needed
- C Banding (centromere)
- NOR (nuclear organizing region)
- R banding (reverse banding pattern)
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Organized procedure for matching and alining the identical chromosome pairs.
It will always state the chromosomal complement and sex.
Karyotype
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Clinical application of Karyotyping
- Chromosomal complement
- Detect structural abnormalities of a chromosome
- Detect numerical variation associated with specific syndromes which allows for early (inutero) diagnosis of chromosomal abnormalities.
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The electrochemical difference between the intracellular and extracellular environment is maintained by what?
The cell membrane
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A Resting Membrane Potential is formed by what?
The inside surface is relatively negative charged than the extracellular space producing a voltege difference or...
membrane potential/ diffusion potential
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Main Cations in membrane
- Intracellular- Potassium
- Extracellular- Sodium
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Main Anions in membrane
Extracellular- Chloride
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Factors contributing in the production of a resting membrane potential (3)
- 1- Unequal distribution of ions across the membrane
- 2- Relative membrane permeability for Na+, K+, and Cl-
- 3. Permeability is 50-100x greater for K+ than for Na+
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The 2 types of electrical signals that muscle and neurons use
- 1- Graded potentials (for short distance communication)
- 2- Action potentials
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Electrical signals produced by neurons and muscles rely on these 4 types of ion channels
- Leakage channels
- Voltage-gated channels
- Ligand-gated channels
- Mechanically gated channels
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These gates are randomly opened or closed to maintain the electrochemical difference (diffusion potential)
eg- cell membrane allows leakage of K+ to maintain electrochemical difference
Leakage gated channels
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Open in response to direct change in membrane channels. Gives neurons and muscle fibers the property of excitability (ability to respond to certain stimuli producing impulses)
Voltage gated channels
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Work in responce to specific chemical stimulii changing membrane permeability
Neurotransmitters
Hormones
Ligand gated channels
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2 types of ligand gated channels
- 1- Direct (Acetylcholine) - Opens channels for Na+, K+, and Ca++
- 2- Indirect - Work via membrane protein (protein G) as second messenger system
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Work in response of vibration, pressure (sound), stretching (pacinian corpuscle), and light (photoreceptors)
Mechanically gated channels
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When a stimulus occurs in ligand gated or mechanically gated channels, it produces a small deviation from the membrane potential producing:
- Hyperpolarization
- Depolarization
- -Occurs in a localized region of the membrane, travels for a short distance, and dies out.
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Action Potential
Electrical signal produced in excitable cells under proper stimulation leading to a sequence of rapidly occuring events that results in:
Depolarization and Repolarization
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Decrease and eventual reversal of membrane potential. Requires a stimuli to depolarize the resting potential to a critical value (threshold)
-depends on Na+ channels (open)
going up the curve
Depolarization
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Restauration of resting state
Depends on K+ channels which do not exhibit an inhibitory state
-Na+ channels close, K+ channels open- down the curve
Repoarization
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The time during which an excitable cell cannot generate another action potential.
Refractory period
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Time in which a second action potential can be initiated by a superthreshold stimulus. Coincides with a period of voltage gated K+ channel open after inactivated Na+ channels have returned to resting state
Relative Refractory Period
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Concincides with the period of Na+ channels activation and inactivation
Absolute refractory period
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Propagation of Action Potential
- Electrical impulse travel dependent on positive feedback.
- Since the membrane is refractory behind the leading edge of the Action Potential, it only moves in one direction.
- Follows the All or none principle
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What is directly related to the diameter of the fiber and the presence or absence of myelin?
Speed of impulse
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Myelinated large diameter fibers conducting the fastest impulses
A fibers
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Small myelinated fibers
B fibers
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Small unmyelinated fibers
C fibers
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Occurs in muscle fibers and unmylinated axons
Continuous conduction
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Occurs in myelinated fibers, is more energy efficient, and travel time is faster
Saltatory conduction
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The transference of the signal or synapses in human cells occurs in 2 different forms:
- Electrical synapses
- Chemical synapses
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Electrical synapse
Occur through gap junctions "connexons"
Allows for faster communication and synchronization
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Chemical synapses (2 things)
- 1- One way transmission
- 2- Promotes a response in post-synaptic target
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Which neurotransmitters are Inhibitory
Gaba and Serotonine
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Which neurotransmitters are Excitatory
- Acetylcholine (cholinergic neurons)
- Glutamate
- Norepinepherine (adrenergic neurons)
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Graded potential characteristics
- Amplitude- Variable sizes, dependent on strength to start it
- Duration- Longer
- Channels- different types
- Location- mainly in dendrites
- Propogation- Localized
- Refractory Period- none
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Action potential characteristics
- Amplitude- same size
- Duration- Quicker
- Channels- Voltage gated ion
- Location- arise at triggered zone propagating along the axon.
- Refractory period- Present
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Body is upright
Anatomical Position
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Body is laying face down
Prone position
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Body is lying face up
Supine position
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Supports the head and attaches to trunk
Neck
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Chest, abdomen, and pelvis
Trunk
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Attaches to trunk (shoulder, armpit, and arm)
Upper limbs
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Attaches to trunk (buttock, thigh, leg, ankle, and foot)
Lower limbs
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Nearer or at the Front of the body
Anterior/ ventral / frontal
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Nearer or at the Back of the body
Posterior/ Dorsal
-
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Away from the head
Inferior
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Nearer to the attachment of a limb to the trunk
Proximal
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Farther from the attachment of a limb to the trunk
Distal
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Farther from the midline
Lateral
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Nearer to the midline
Medial
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Imaginary flat surfaces that pass through the body parts
Planes and Sections
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A vertical plane that divides the body into right and left sides
Sagittal plane
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Divides the body into equal right and left sides
Midsagittal
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Divides the body into unequal right and left sides
Parasagittal plane
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Divides the body or an organ into anterior and posterior portions.
Frontal or Coronal plane
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Divides the body or an orgain into superior and inferior portions.
- Transverse plane
- Also, cross sectional or horizontal plane
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Passes through the body or an organ at an angle
-Between transverse and sagittal or between transverse and frontal
Oblique plane
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Spaces within the body that help protect, separate, and support the internal organs
Body cavities
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Formed by the cranial bones
Protects the brain
Cranial cavity
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Formed by bones of vertebral column
Contains the spinal cord
Vertebral cord
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Layers of protective tissue that line the cranial cavity and vetebral canal.
Meninges
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Thoracic Cavity is formed by:
- Ribs
- Muscles of the chest
- Sternum (brestbone)
- Vertebral column (thoracic portion)
-
2 cavities within the thoracic cavity
Pericardial Cavity
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Extends from the diaphragm to the groin
Abdominopelvic cavity
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Abdominal cavity
Stomach, Spleen, Liver, Gallbladder, Small and Large Intestine
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Pelvic Cavity
Urinary Bladder, Inernal organs of reproductive system, and portions of the large intestine.
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Nine Abdominopelvic Regions
- R & L Hypochondriac
- Epigastric and Hypogastric
- Right and Left Lumbar
- Right and Left Inguinal
- Umbilical
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Vertical and horizontal likes that pass through the umbilicus
- Quadrants
- RUQ, LUQ, RLQ, LLQ
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Other Cavities
- Oral cavity
- Nasal cavity
- Orbital cavities
- Middle ear cavities
- Synovial cavities
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An organized aggregation of cells that function in a collective manner
Tissue
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Gap Junctions
- Sites that mediate electric coupling between cells. Also permit the prederential passage of small molecules from cell to cell.
- Intercellular channels that permit the free passage between the cells of ions and small molecules.
- They are cylinders constructed form the 6 copies of transmembrane proteins called connexins.
- Permit changes in membrane potential to pass from cell to cell.
- Ex- heartbeat, electrical synapses in
- the brain
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4 tissue types
- Epithelium
- Connective Tissue
- Muscular Tissue
- Nervous Tissue
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A Pas positive + recation means:
The presence of polysaccharides
-
Description of Pseudostratified epithelia
- all cells rest on the basement membrane,
- only some cells reach the free surface,
- Actually, a simple epithelium. (stratisfied should have two or more layers)
- Has limited Distrubtion in the body
- Reflects the role of stem cells in maintaining a stable population of cells to balance cell turnover.
- ex- Pseudostratisfied columnar
- epithelium of the trachea
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Epithelia involved in secretion and/or absorbtion are typically what type:
Simple or Pseudostratisfied
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What are Goblet cells?
- Single cells in the epithelium that have secretory function. They secrete a mucous substance.
- Are unicellular glands.
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What are the characteristics of a Secretory Cell
- Have a well developed ER
- A Golgi apparatus to fulfill their function
- Numerous mitochondria
- Vesicles and granules
- Multiple join together to form multicellular glands
- Most in humans are cuboidal columnar
- Ex- cells of epithelium of GI tract that
- secrete digestive enzymes and gastric acid, or Meibomian glands in the eyelid
- that secrete sebum to lubricate and protect the eye.
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3 ways that exocrine glands release their products
- Merocrine
- Apocrine
- Holocrine
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Merocrine
- Cells that secrete products via this method form membrane-bound secretory vesicles internal to the cell.
- These are moved to the apical surface where the vesicles coalesce with the membrane on the apical surface to release the product.
- Most common- Most glands release their products this way.
-
Apocrine Glands
- In glands that release the product via this method, the apical portions of cells are pinched off and lost during the secretory process.
- This results in a secretory product that contains a variety of molecular components including those of the membrane.
- Mammary Glands release their products in this manner.
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Holocrine Glands
- The type of secretory release that involves cell death.
- The secretory cells is released and as it breaks apart, the contents of the cell become the secretory product.
- This mode of secretion results in the most complex secretory product.
- Some sweat glands in the axillae, pubic areas, and areoli of breasts use this method.
- Sebaceous glands are also this type
-
Paracrine Glands
- Secretory cells of endocrine glands that can release their substance into the adjacent cells or surrounding tissue rather than into the bloodstream.
- Function is _____ signaling
- Ex- growth factors, clotting factors.
- Overproduction of some of these growth factors have been linked to the development of cancer.
-
Autocrine glands
- Secretory cells that also release their hormones into the surrounding cells in the tissue.
- The chemical agent, or hormone, affects cells of the same type.
- The function is _________ signaling
-
A form of signaling in which a cell secreated a hormone (or chemical messenger) that binds to autocrine receptors on the same cell, leading to changes in the cell.
Autocrine Signaling
- Examples- T cell lymphocytes
- Cytokine interleukin 1- in monocytes
-
What are Macula Adherens
A focal junction- a spot in the cell membrane where adhesion occurs.
-
What are Zonula Adherens?
- A Band junction- the area of adhesion that surrounds cell membanes.
- Usually found adjacent to zonla occlusions
- Found in the intercellular junctions of the RPE
- Between the Muller cells of the Retina
- At the Myoid portion of the photoreceptors of the retina forming the outer limiting membrane of the retina.
-
Differences in Macula and Zona Occludens
- Both are associated with a keratin-based cytoskeleton.
- Macula possess specific transmembane receptors of the integrin family that link the cell to the extracellular matrix on the outside of the cell and the microfilament system on the inside.
- Zonula has members of a family of calcium ion-dependent cell adhesion molecules, called Ca-adherens, that mediate attachment between cells at junctions.
-
What the Macula and Zonula Occludens do:
- They join cells together or to the extracellular matrix.
- Transduce signals into and out of the cell, including proliferation, migration, and differentiation.
- Some components can shuttle to and from the nucleus where they are thought to play a role in regulating gene
- expression.
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What are Desmosomes
- Same as macula adherens but:
- There is a “cellular bridge”
- Present an electron-dense intercellular material parallel to the cell membrane, forming a line.
- Present numerous tonofilaments in the cytoplasm oriented at right angle with respect to the cell junction
- Found in the epidermis, corneal epithelium, optic cup epthelium, and the CNS.
-
What are Hemidesmosomes
- Half desmosomes
- A special type of desmosomes found at the base of epithelial cells
- Fasten the epithelium to the basement membrane
-
How are fibers organized in the dense regular connective tissue? (tendons)
The fibers are all aligned in a single direction, conferring tensile strength primarily in that direction.
-
Function of Mast cells?
Secretory alarm cells. Upon the slightest disturbance, they release chemical signals which diffuse through the surrounding ground substance and trigger the process of inflammation.
-
What is the secretion of the Osteoblasts?
deposit a matrix of Type-1 collegen and also release calcium, magnesium, and phosphate ions that combine within the collagenous matrix into crystalline mineral, known as bone mineral.
-
What are Osteoclasts?
macrophage relatives which dissolve bone matrix.
-
What are the Haversian canals
- the central canal where the concentric lamellae (the osteon’s concentric layers of mineralized matrix) are deposited.
- (compact bone has these)
-
What are Volkmann canals?
Known as perforating holes, are microscopic structures found in compact bone. They run within the osteons perpendicular to the Haversian canals, interconnecting the latter with each other and the periosteum. They usually run at obtuse angles to the Haversian canals and contain anastomosing vessels between Haversian capillaries. They also carry small arteries throughout the bone.
-
Direct Function of bone tissue
- Support for muscles, organs, and soft tissue
- Leaverage and movement
- Protection of vital organs
- Calcium phosphate storage
-
Indirect Function of Bone tissue
Hemopoiesis- formation of blood cells by the bone marrow interspersed within the spongy bone.
Main blood production is in the spleen and liver
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What is Epithelioid tissue? Examples
- They are interstincial cells of leydig of the testis
- Examples: luteal cells of the ovary, parenchyma of adrenal glands, epithlioreticular cells of thymus
-
The Lacrimal gland
- Composed of tubuloacinar gland
- Is a combination gland
-
Classification of the Sclera connective tissue?
Dense collagenous tissue
-
Classificarion of the Cornea connective tissue
Dense fibrous connective tissue
-
Classification of Corneal epithelium
non-keratinized stratified squamous
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