Lecture 2 Flashcards
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What are the 5 organelles mentioned in class?
Peroxisomes, lysosomes, mitochondria, Golgi apparatus, endoplasmic reticulum transport vesicles
Categorize proteins.
Structural - helping the cell hold shape; barrier (allow or force something across the cell wall)
Functional - enzymes, receptors
What does glycolysis require? What does it produce? Where does it take place?
Sugar
ATP
Inside the cell/mitochondria
What charge does sugars have? And how does this affect proteins?
They have a negative charge and can repel negatively charged proteins. Used in the kidneys to repel protein
What is are the sugar/starch prefixes?
Glyco-
Carb-
Carboxy-
What are key characteristics of sugar?
It is sticky; can be used as ID tags that are different from bacteria/virus ID tags
How does sugar being sticky affect other cells?
It allows other cells to stick and hold together. Sometimes the body looks at this as a foreign cell and will activate an immune response.
What is a carboxyhemoglobin?
Sugar and hemoglobin. It is less functional
What does the mitochondria do?
Helps produce ATP
Briefly describe Mitochondrial DNA
Differs from human DNA; All Mitochondrial DNA is inherited from mother; We receive 12-20 sets
What are 2 motility structures?
Flagella - moves the actual cell
Cilla - moves substances around the cell
What is genetic material?
DNA and RNA
What is a major component in turning the cell on and off?
The cell wall; Calcium
What is hydrophilic?
“water loving”; positively charged molecules love water.
What happens when you put an electrolyte compound in water?
It falls apart; Ex) NaCl- will dissociate when dissolved in a solution
Describe a lipid
A fat that is non charged; likes oily substances; likes to hang in the middle of cell wall
What are the functions of sugars inside vs outside of the cell?
Inside:
Used for energy - glucose used to make ATP
Outside:
- Identification: ID tags; glycoproteins attached to cell walls
- STICKY (adherens)
- Structural function
- External sugars have negative charge, repel (-) charged proteins floating around.
What is an enzyme
Protein that catalyzes (speeds up) reactions. End in -ase
What are the 3 types of lipids found in the cell membrane
Phospholipids, sphingolipids (nerve cells), cholesterol
What is the function of cholesterol in the cell wall
Provide rigidity- prevent from being too fluid/flexible
What does soluble/hydrophilic drug need to cross the cell membrane?
Carrier protein
What is arachidonic acid
Important precursor molecule, used to generate signaling compounds
Metabolized from phospholipids.
Lipid soluble; long chain fatty acid found in the cell wall.
Cox1 and 2 turn AA into _________
prostaglandins
Cytochrome p450 turns AA into ________
HETE and EETS
Lipooxygenase turns AA into _________
leukotrienes
Where are lipids synthesized
Smooth ER
Are fats/lipids charged or uncharged?
Uncharged
What are the 6 “soluble” substances?
- Ions (electrolytes)
- Proteins (somewhat): the parts of protein that are exposed to water
- Carbohydrates: tend to be charged compounds (glucose)
- Gasses (depends): some soluble in water, CO2
- Buffers: found in all containers in the body. Keep pH balanced
- Drugs (some) - look at container that drug is in
What substances are insoluble?
Cholesterol
Steroid Hormones
Lipids- comprise majority of cell wall
Drugs (others) - look oily then insoluble ex. Propofol
Gasses (depends): N2O (nitrous oxide)
What percent of our mass is total body water?
60% of body mass
What fraction of our ECF is interstitial fluid?
¾-⅘
What percent of our TBW is ECF
1/3
What percent of our TBW is intracellular
2/3
What % of the cell is water?
70-85%, except for adipose
What fraction of our ECF is plasma
¼-⅕ of ECF
What is the ratio of K+ in the ICF vs ECF?
30x more K+ in the ICF than ECF
Would an obese person have a higher or lower % of TBW compared to non-obese?
Obese person would have lower % TBW because they have a higher ratio of adipose tissue that have very little water.
lower fluid to weight ratio
Is HCO3 found more in the ECF or ICF?why?
More in the ECF
HCO3 is the most important buffer
Is the capillary membrane more or less permeable compared to cell membrane?
More, with the exception of the bood brain barrier
What is the normal value of sodium in the ECF
140 mOsm/L H2O
What is the normal value of sodium in the ICF
14 mOsm/L H2O
What is the ratio of sodium between the ECF and ICF
ECF is 10x the amount in ICF
What is the normal value of K+ in the ECF?
4 mOsm/L H2O
What is the normal value of K+ in the ICF?
120-140 mOsm/L H2O
Is ATP found more predominantly in the ECF or ICF?why?
ICF
Main energy source in cells, too valuable to leave the cell.
Is HPO4- found more in the ECF or ICF? why?
More in the ICF
Primary buffer of ICF
on/off switch in cells by phosphorylation
Think ATP, adenosine + 3 phosphates
Is calcium found more in the ECF or ICF? Why?
ECF
Calcium primarily used as signal to turn on cells. Very little inside of cells
Is Mg++ found more in the ECF or ICF? Why?
More in ICF. Mg++ is important cofactor in many reactions inside the cell. Decreases heart activity
Is Cl- found more predominately in the ECF or ICF?
ECF
Cl- is the primary anion of ECF; follows Na+
Is creatine found primarily in the ECF or ICF? Why?
ICF
Creatine is a powerful source of energy in cells, but it depletes fast and only have small amounts
Is Protein found more predominantly in the ECF or ICF?why?
ICF
Produced by cells and used by cells to complete specialized tasks
Some protein in ECF, primarily albumin
Which functions of sugar are inside vs outside of the cell?
Inside= glycolysis and structural
outside= identification, adherence, repel (-) charged proteins
Are amino acids found more in the ECF or ICF? Why?
ICF
Proteins are made from chains of amino acids inside the cells
Is lactate found more predominantly in the ECF or ICF?why?
ICF
Lactate is a bi-product of cell metabolism
What is total osmolality? What is normal value?
The sum of how many ions/electrolytes are in a volume, expressed in mOsm/kg
300 mOsm/kg H2O
Without a mediator the cell wall will not let ___________ permeate
Charged ions/molecules, i.e. hydrophilic particles
What is the corrected osmolar activity? What is normal value
Osmolarity should be pretty consistent because water movement is not inhibited. Water can move in and out to correct concentrations
280-283 mOsm/L H2O
The most notable difference between the plasma compartment and interstitial compartment of the ICF is the ________
Protein concentration
More in the plasma compartment. Think albumin
What is a quick method of calculating blood osmolarity?
Doubling the value of ECF sodium
140 x 2 = 280
Attaching phosphates for energy storage is called _______?
Phosphorylation
What is the main energy source in the cell?
ATP (adenosine triphosphate)
Why do we correct for osmolarity?
Not all particles are freely dissociated from one another
Oppositely charged particles tend to attract each other
Na+ and Cl- may bond and act less like individual particles
Biologic osmolarity (280-283) actually lower than theoretical (300)
Removing phosphates for energy consumption is called _______?
Dephosphorylation
Why is osmolarity consistent across all compartments?
Water movement is not inhibited by membranes
Water will shift from high concentration to low to balance concentrations
What are some characteristics of cholesterol?
Planar (flat)
Rigid
Lipid soluble
What is the function of the -OH group of cholesterol?
Cholesterol lives in the cell wall
-OH group is polar and sticks out of the cell wall. Body can use the -OH group to remove the cholesterol if needed
What are the functions of the glycocalyx?
Helps cells attach to each other - think STICKY
Receptors
Immune function and cell identification
Negatively charged sugars repel other negatively charged particles
How does temperature affect membrane fluidity?
Normal temp - rigid and planar
Low temps- increases membrane fluidity
Used in foods to affect texture, ex. Ice cream
How does uncontrolled diabetes affect the cell membrane and immune response?
Sugars used for cell identification on the exterior of the cell membrane
Higher amount of external sugars makes cells look foreign, causing immune system response
What is amphipathic?
Has both hydrophobic and hydrophilic parts
Phospholipid: outside/charged (phosphate head) is hydrophilic (charged) and inside (lipid tail) is hydrophobic (uncharged)
What is the glycocalyx?
Carbohydrate coating surrounding the outside of cell
Sum of all external sugar structures on the cell wall
Glycoproteins+glycolipids = glycocalyx
What makes up the bulk of the cell wall
phospholipid tails
Body temperature and rigidity of cholesterol are ______proportional
Directly proportional (normal temperature stiff/Low temperature more fluid like ice cream)
Sex hormone formation requires _______
Cholesterol
Long chains of hydrogens and carbons form ________
lipids
adenosine in the ECF
increases blood flow to meet metabolic demand
Adenosine can leave the cell if
The cell is metabolically active; all the phosphates are pulled off
Our cells are reliant on an external sources of ________
Glucose
How many ATP does glycolysis produce?
2
Capillary membrane prevents __________ from permeating to interstitial fluid
- CV (plasma) proteins
Where is calcium stored in the cell?
ER
__________ is an energy storage molecule used by muscle tissue
Phosphocreatine - the phosphate from creatine phosphate can be removed and attached to an ADP to generate ATP quickly.
Steady state vs equilibrium
“Steady state” has tightly regulated differences; Equilibrium tries to maintain same concentrations (we don’t want our body temperature and environmental temperature to be equal)
An example of an insoluble drug utilizing a lipid-based carrier system is
propofol
What components make up ECF?
Plasma and interstitial fluid
ECF: ICF calcium
10,000:1
Protein concentration ICF:ECF
5:1
ATP production starts in the ________ with anaerobic metabolism (glycolysis)
Cytosol
What enzyme is found in peroxisomes that breaks down hydrogen peroxide?
Catalase
