Week 1 - Cellular Biology Flashcards
Describe the cell membrane and function
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Phospholipid bilayer – 2 layer
- Hydrophilic head (Phos) – love water
- Hydrophobic tail (lipid) – repells water
- Water soluble hormones outside of cell can’t go through membrane, lipid hormones slide through (O2 and CO2 are lipids)
- selective
- Protection
- Gates
- Receptors
- Protein channels
Nucleolus
- DNA (mayor) – never leaves the nucleolus
- RNA (sends mRNA out of the nucleolus to nucleus)
Nucleus Primary Function
cell division and control of genetic information
Mitochondria Fx
- Produce ATP (cellular respiration and energy production)
- Oxidative phosphorylation
- Lysosome
- Intracellular autophagy and autodigestion (digest cells into basic components)
- Peroxisome
- Oxidative enzyme that make peroxide (H2O2) (use O2 to remove hydrogen atoms); major sites of oxygen utilization
- Centrioles
- Important when the cell divides
Cytoplasm:
- fills the space between the nuclear envelop and the plasma membrane
- Maintains structure of cell, ½ cell volume
- Allows for motility (squeezing cell through spots)
- Contains cytoplasmic organelles
- Contains metabolic enzymes/processes, ribosomes,
- protein synthesis and transport & Isolates and eliminates wasts
- Stores fat, carbohydrates, and secretory vesicles
- Cytosol is liquid in cytoplasm (55% of cell)
Endoplasmic reticulum
- (conveyor belt) network of tubular or saclike channels
- Site of protein synthesis; senses cellular stress
- Smooth – no ribosome
- Rough – ribosome
Ribosome:
- protein synthesis (ribonucleic acid/RNA protein complexes)
- Hard working people to make proteins
- Proteins tell the body what to do
- Science can make proteins
- Attached to ER or float in cytoplasm
- Golgi Apparatus:
- package proteins from ER by folding proteins 4 times
- secrete vesicles and cisternae
- Specialized Cell Junctions
- adherens
- Desmosomes
- Hemidesmosomes
- Adherens: rubber band, seal
- Desmosomes: anchors between cells
- Hemidesmosomes: anchored to bottom of cell
Junctional complexes
- : desmosome, tight junction (homostasis), gap junction (window to open up), connexons, gates
Cellular communication:
Paracrine
Autocrine
Hormonal
Neurohormonal
Neurotransmitters
Chemical synapses
- Cellular communication: maintains homeostatis; regulates growth and division; coordinates functions
- Paracrine signaling: send information to neighborhood (local area)
- Autocrine signaling (
- Hormonal signaling: entire body
- Neurohormonal signaling: from brain, oxytocine and ADH
- Neurotransmitters: nerve to nerve communication
- Chemical synapses: within nerve
- Cellular Metabolism 3 steps
-
Glycolysis: breaking down to energy (glucose pyruvate)
- Oxidative cellular metabolis
- occurs in the cytoplasm
- 6 ATP for 1 glucose molecule
- Citric acid cycle (Krebs cycle or tricarboxylic acid cycle)
- Oxidative Phosphorylation: occurs in mitochondria and produces ATP from carbs, fats, and proteins
Anabolism
Catabolism
- Anabolism: uses energy (use ATP) “pay ana”
- Catabolism: releases energy, creates energy
ATP 2 functions
- Created from chemical energy contained in organic molecules (carbs, lipid, proteins are catabolized to make ATP)
- Used to create organic molecules, muscle contraction, and active transport
- Functions:
- Stores and transfer of energy
- Energy is always transferred (2nd law of neuton)
Passive transport
Activie transport
- Passive – no ATP, water or small electrically uncharged molecules move through pores
- Active – use ATP/metabolic energy, occurs across living membranes, requires energy
3 Types of Passive Transport
- Diffusion
- A solute move from greater concentration to less concentration
- Concentration gradient
- Size and lipid solubility affects rate of diffusion
- Filtration: Hydrostatic Pressure
- Greater for force moves water and solutes across a membrane
- Osmosis (same as diffusion but only water)
- Water moves “down” a concentration gradient (high to low)
- Osmotic pressure: The amount of hydrostatic pressure required to oppose the osmotic movement of water
- Oncotic pressure or colloid osmotic pressure: The overall osmotic effect of colloids, such as plasma proteins
- Osmolarity (lari): how much/number solute in liquid, measured milliosmoles per liter or molecules per volume. Heat will change volue.
- Heat will change the volume of liquid – alters osmolarity
-
Osmolality (lali): weight of solute in liquid, measured in milliosmoles per kilogram of water
- Heat won’t influence
Tonicity
Isotonic
Hypertonic
Hypotonic
- Intracellular fluid (ICF) and Extracellular fluid (ECF) 285 mOsm/kg
- Isotonic: same osmolality or concentration (Normal saline)
- Hypertonic: concentration of more than 285-294, give solution cell shrinks (3%) – pulls fluid out of cells
- Hypotonic: lower concentration; more dilute than body fluids, Gatorade, pedialyte - cells swell
Electrolyte shifts in active transport and necessary elements
-
Active Transport of Na+ and K+
- Na+ moves out of and K+ moves into the cell
- Uses ATP
Electrogenic
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Active Transport of Na+ and K+
- Na+ moves out of and K+ moves into the cell
- Uses ATP
- Electrogenic: electrical potential where inside of cell is more negative than outside
- For every ATP molecule hydrolyzed, 3 Na+ are transported out of the call and 2 K+ into the cell
Types of active Transport
Electrolyte shifts - electrogenic
Endocytosis (pinocytosis & Phagocytosis)
Endocytosis
Exocytosis
Endocytosis and its two types
- Endocytosis: taking in (enfolds substance from out side of cell > endocytic vesicle into cell)
- Pinocytosis: cell ingestion of ECF and its contents
- Phagocytosis: large molecules are engulfed by cell membrane so lysosomes can destroy (macrophage)
Endocytosis and Exocytosis
- Endocytosis: taking in
- Exocytosis: expel
Describe movement of electrical impulses
Action potential Phase
D
T
R
H
RP
- Resting membrane potential: difference in voltage across the plasma membrane (inside cell more negatively charged)
- Action Potential
- Depolarization (charging up, buying at Home Depot)
- Threshold potential (go time, no going back)
- Repolarization (charging down)
- Refractory period (nothing going, male orgasm)
- Absolute (not possible) and relative (maybe)
- Hypopolarization (being excited) and hyperpolarization (coming down)
- Resting Potential (RP):
- Lots of Na outside of cell 135-145, potassium in the cell 3.5-4.5
4 phases of Interphas
5 phases of Mitosis
Do all cells go through this?
- Interphase
- G1 phase – gap (growing)
- S phase – DNA synthesis (making double of chromosome) 46
- G2 phase – RNA and protein synthesis (cell getting bigger)
- Mitosis Phase – mitosis (making more cells) PMATC – ready to Marry and have kids
- Prophase – condensation of the chromosome
- Metaphase – chromosomes meet in the middle
- Anaphase – chromosomes go away
- Telophase – go way apart (cleavage) – chromosomes have to call each other so far away
- Cytokinesis – new cell
- Some cells do not replicate – some muscles, nervous system?, back of eye
Cytokines
- Growth factors (also called cytokines): platelet-drived growth factor stimulates connective tissue growth
- Negative feedback
- Controlled by receptors, hormone, nervous system, and enzymes
- Opposite: fever, BG
- Plasmin, Antithrombin > X and II
- positive feedback
- Controlled by receptors, hormone, nervous system, and enzymes
-
Alike: up/up or down/down
- FSH/LH
- Labor
- factors V, VII, VIII, XI, XIII
Atrophy
- decreased/shrinkage in cellular size (leg muscle)
Hypertropy
-
Hypertrophy: increase in size of cells
- Physiological – light legs
- Pathological – heart muscle, liver, spleen
Hyperplasia
-
Hyperplasia: more cells
- Physiological – menses
- Pathological – beginning of CA, moles
Metaplasia:
-
Metaplasia: reversible replacement of mature cell type by another
- Pathological: epithelium in smokers
Dysplasia:
- abnormal and irreversible changes in size, shape and organization of mature cells (can lead to CA)
Osteoporosis type of cell change
Atrophy
Hemochromatosis
Autosomal recessive
Increase Serum Fe, Ferritin
Gray or bronze skin tone
Iron deposits in liver, pancrease, heart joints, anterior pituitary and other organs
Wilson’s Disease
Autosomal Recessive
Increase copper in blood
lack ATP7B
ATP7B normally binds to Copper > ceruloplasmin
Test: copper, ceruloplasmin, Kayser-Fleicher Rings
s/s: hepatitis, neurologic issues
Treatment:
- pencillamine (antihistamine, kelating CU & remove through urine
- Zinc + Ammonium tetrathiomolyodate (binds with Cu)
Free Radicals
- Causes: metablisms, diseases, UV light, radiation, air pollution, smoking, inflammation
- Free radicals try to steal an electron from another part of cells (i.e. erosion of cell membrane)
- *Unpaired electron in outer orbital*
- Reduction (GER): gain an electron
- Oxidation: lose an electron
- Treatment A,C,E (ACE) vitamins & Glutathion
Apoptosis
- programmed cell death, cells have a programmed time frame
-
Cellular Necrosis (autolysis)
- Coagulative
- Liquifactive
- Caseous
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Fat
- Gangrenous
Coagulative: denaturation of proteins fromm gel to firm state (kidneys, cardiac infarct)
Liquefactive: cells digested by their own hydrolases > softening tissue > walled off cyssts (bacterial infections, cerebreal infarct)
Caseous: cells disintegrte/denature but debris is walled off (TB, granulomas; combo of cogagulative and liquefactive)
Fat: caused by lipase (pancrease, breast tissues) sponification
Gangrenous: dry (ischemia) and wet types (liquefactive, bacteria), due to injury