Week 1 - Cellular Biology

Question 1

Describe the cell membrane and function

Answer 1

1. Phospholipid bilayer – 2 layer
   
   1. Hydrophilic head (Phos) – love water
   2. Hydrophobic tail (lipid) – repells water
   3. Water soluble hormones outside of cell can’t go through membrane, lipid hormones slide through (O2 and CO2 are lipids)
   4. selective
2. Protection
3. Gates
   
   1. Receptors
   2. Protein channels

Question 2

Nucleolus

Answer 2

1. DNA (mayor) – never leaves the nucleolus
2. RNA (sends mRNA out of the nucleolus to nucleus)

Question 3

Nucleus Primary Function

Answer 3

cell division and control of genetic information

Question 4

Mitochondria Fx

Answer 4

1. Produce ATP (cellular respiration and energy production)
2. Oxidative phosphorylation

Question 5

1. Lysosome

Answer 5

1. Intracellular autophagy and autodigestion (digest cells into basic components)

Question 6

1. Peroxisome

Answer 6

1. Oxidative enzyme that make peroxide (H2O2) (use O2 to remove hydrogen atoms); major sites of oxygen utilization

Question 7

1. Centrioles

Answer 7

1. Important when the cell divides

Question 8

Cytoplasm:

Answer 8

1. fills the space between the nuclear envelop and the plasma membrane
   
   1. Maintains structure of cell, ½ cell volume
   2. Allows for motility (squeezing cell through spots)
   3. Contains cytoplasmic organelles
   4. Contains metabolic enzymes/processes, ribosomes,
   5. protein synthesis and transport & Isolates and eliminates wasts
   6. Stores fat, carbohydrates, and secretory vesicles
   7. Cytosol is liquid in cytoplasm (55% of cell)

Question 9

Endoplasmic reticulum

Answer 9

1. (conveyor belt) network of tubular or saclike channels
   
   1. Site of protein synthesis; senses cellular stress
   2. Smooth – no ribosome
   3. Rough – ribosome

Question 10

Ribosome:

Answer 10

1. protein synthesis (ribonucleic acid/RNA protein complexes)
   
   1. Hard working people to make proteins
   2. Proteins tell the body what to do
   3. Science can make proteins
   4. Attached to ER or float in cytoplasm

Question 11

1. Golgi Apparatus:

Answer 11

1. package proteins from ER by folding proteins 4 times
2. secrete vesicles and cisternae

Question 12

1. Specialized Cell Junctions
   
   1. adherens
   2. Desmosomes
   3. Hemidesmosomes

Answer 12

1. Adherens: rubber band, seal
2. Desmosomes: anchors between cells
3. Hemidesmosomes: anchored to bottom of cell

Question 13

Junctional complexes

Answer 13

1. : desmosome, tight junction (homostasis), gap junction (window to open up), connexons, gates

Question 14

Cellular communication:

Paracrine

Autocrine

Hormonal

Neurohormonal

Neurotransmitters

Chemical synapses

Answer 14

1. Cellular communication: maintains homeostatis; regulates growth and division; coordinates functions
   
   1. Paracrine signaling: send information to neighborhood (local area)
   2. Autocrine signaling (
   3. Hormonal signaling: entire body
   4. Neurohormonal signaling: from brain, oxytocine and ADH
   5. Neurotransmitters: nerve to nerve communication
   6. Chemical synapses: within nerve

Question 15

1. Cellular Metabolism 3 steps

Answer 15

1. Glycolysis: breaking down to energy (glucose pyruvate)
   
   1. Oxidative cellular metabolis
   2. occurs in the cytoplasm
   3. 6 ATP for 1 glucose molecule
2. Citric acid cycle (Krebs cycle or tricarboxylic acid cycle)
3. Oxidative Phosphorylation: occurs in mitochondria and produces ATP from carbs, fats, and proteins

Question 16

Anabolism

Catabolism

Answer 16

1. Anabolism: uses energy (use ATP) “pay ana”
2. Catabolism: releases energy, creates energy

Question 17

ATP 2 functions

Answer 17

1. Created from chemical energy contained in organic molecules (carbs, lipid, proteins are catabolized to make ATP)
2. Used to create organic molecules, muscle contraction, and active transport
3. Functions:
   
   1. Stores and transfer of energy
   2. Energy is always transferred (2^nd law of neuton)

Question 18

Passive transport

Activie transport

Answer 18

1. Passive – no ATP, water or small electrically uncharged molecules move through pores
2. Active – use ATP/metabolic energy, occurs across living membranes, requires energy

Question 19

3 Types of Passive Transport

Answer 19

1. Diffusion
   
   1. A solute move from greater concentration to less concentration
   2. Concentration gradient
   3. Size and lipid solubility affects rate of diffusion
2. Filtration: Hydrostatic Pressure
   
   1. Greater for force moves water and solutes across a membrane
3. Osmosis (same as diffusion but only water)
   
   1. Water moves “down” a concentration gradient (high to low)
   2. Osmotic pressure: The amount of hydrostatic pressure required to oppose the osmotic movement of water
   3. Oncotic pressure or colloid osmotic pressure: The overall osmotic effect of colloids, such as plasma proteins
   4. Osmolarity (lari): how much/number solute in liquid, measured milliosmoles per liter or molecules per volume. Heat will change volue.
      
      1. Heat will change the volume of liquid – alters osmolarity
   5. Osmolality (lali): weight of solute in liquid, measured in milliosmoles per kilogram of water
      
      1. Heat won’t influence

Question 20

Tonicity

Isotonic

Hypertonic

Hypotonic

Answer 20

1. Intracellular fluid (ICF) and Extracellular fluid (ECF) 285 mOsm/kg
2. Isotonic: same osmolality or concentration (Normal saline)
3. Hypertonic: concentration of more than 285-294, give solution cell shrinks (3%) – pulls fluid out of cells
4. Hypotonic: lower concentration; more dilute than body fluids, Gatorade, pedialyte - cells swell

Question 21

Electrolyte shifts in active transport and necessary elements

Answer 21

1. Active Transport of Na+ and K+
   
   1. Na+ moves out of and K+ moves into the cell
   2. Uses ATP

Question 22

Electrogenic

Answer 22

1. Active Transport of Na+ and K+
   
   1. Na+ moves out of and K+ moves into the cell
   2. Uses ATP
   3. Electrogenic: electrical potential where inside of cell is more negative than outside
      
      1. For every ATP molecule hydrolyzed, 3 Na+ are transported out of the call and 2 K+ into the cell

Question 23

Types of active Transport

Answer 23

Electrolyte shifts - electrogenic

Endocytosis (pinocytosis & Phagocytosis)

Endocytosis

Exocytosis

Question 24

Endocytosis and its two types

Answer 24

1. Endocytosis: taking in (enfolds substance from out side of cell > endocytic vesicle into cell)
   
   1. Pinocytosis: cell ingestion of ECF and its contents
   2. Phagocytosis: large molecules are engulfed by cell membrane so lysosomes can destroy (macrophage)

Question 25

Endocytosis and Exocytosis

Answer 25

1. Endocytosis: taking in 2. Exocytosis: expel

Question 26

Describe movement of electrical impulses Action potential Phase D T R H RP

Answer 26

1. ![]() Resting membrane potential: difference in voltage across the plasma membrane (inside cell more negatively charged) 2. Action Potential 1. Depolarization (charging up, buying at Home Depot) 2. Threshold potential (go time, no going back) 3. Repolarization (charging down) 4. Refractory period (nothing going, male orgasm) 1. Absolute (not possible) and relative (maybe) 5. Hypopolarization (being excited) and hyperpolarization (coming down) 6. Resting Potential (RP): 7. Lots of Na outside of cell 135-145, potassium in the cell 3.5-4.5

Question 27

4 phases of Interphas 5 phases of Mitosis Do all cells go through this?

Answer 27

1. Interphase 1. G1 phase – gap (growing) 2. S phase – DNA synthesis (making double of chromosome) 46 3. G2 phase – RNA and protein synthesis (cell getting bigger) 4. Mitosis Phase – mitosis (making more cells) **PMATC** – ready to Marry and have kids 1. **Prophase –** **condensation of the chromosome** 2. Metaphase – chromosomes meet in the middle 3. Anaphase – chromosomes go away 4. Telophase – go way apart (cleavage) – chromosomes have to call each other so far away 5. Cytokinesis – new cell 5. Some cells do not replicate – some muscles, nervous system?, back of eye

Question 28

Cytokines

Answer 28

1. Growth factors (also called **cytokines):** platelet-drived growth factor stimulates connective tissue growth

Question 29

1. **Negative feedback**

Answer 29

1. **Controlled by receptors, hormone, nervous system, and enzymes** 2. **Opposite: fever, BG** 3. **Plasmin, Antithrombin \> X and II**

Question 30

1. **positive feedback**

Answer 30

1. **Controlled by receptors, hormone, nervous system, and enzymes** 2. **Alike: up/up or down/down** 1. **FSH/LH** 2. **Labor** 3. factors V, VII, VIII, XI, XIII

Question 31

Atrophy

Answer 31

1. **decreased/shrinkage in cellular size (leg muscle)**

Question 32

Hypertropy

Answer 32

1. **Hypertrophy: increase in size of cells** 1. **Physiological – light legs** 2. **Pathological – heart muscle, liver, spleen**

Question 33

Hyperplasia

Answer 33

1. **Hyperplasia: more cells** 1. **Physiological – menses** 2. **Pathological – beginning of CA, moles**

Question 34

Metaplasia:

Answer 34

1. **Metaplasia: _reversible_ replacement of mature cell type by another** 1. **Pathological: epithelium in smokers**

Question 35

Dysplasia:

Answer 35

1. **abnormal and irreversible changes in size, shape and organization of mature cells (can lead to CA)**

Question 36

Osteoporosis type of cell change

Answer 36

Atrophy

Question 37

Hemochromatosis

Answer 37

Autosomal recessive Increase Serum Fe, Ferritin Gray or bronze skin tone Iron deposits in liver, pancrease, heart joints, anterior pituitary and other organs

Question 38

Wilson's Disease

Answer 38

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: 1. pencillamine (antihistamine, kelating CU & remove through urine 2. Zinc + Ammonium tetrathiomolyodate (binds with Cu)

Question 39

Free Radicals

Answer 39

1. Causes: metablisms, diseases, UV light, radiation, air pollution, smoking, inflammation 2. Free radicals try to steal an electron from another part of cells (i.e. erosion of cell membrane) 3. \*Unpaired electron in outer orbital\* 4. Reduction (GER): gain an electron 5. Oxidation: lose an electron 6. Treatment A,C,E (ACE) vitamins & Glutathion

Question 40

Apoptosis

Answer 40

1. programmed cell death, cells have a programmed time frame

Question 41

1. **Cellular Necrosis (autolysis)** 1. **​Coagulative** 2. **Liquifactive** 3. **Caseous** 4. **Fat** 1. **Gangrenous**

Answer 41

**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**