Test 1

What is one structural difference blw skeletal and cardiac muscle ?

Cardiac muscle Cells are seperated by intercalated discs

What cIasses of Cells make up the organs of the body

all 4 classes of cells are found in the body but the proportions of each may differ depending on the Organ function

What is meant by epithelial cell paracellular transport vs transcellular transport ?

diffusion in blw cells is paracellular while movement from interstitial space through baso lateral membrane into epithelial call then thru luminal membrane into tube or organ is transcellular

What would be the normal plH for blood ?

7\.38 \~ 7:45

A solution with a hydrogen ion concentration of 1x10\* -x would have what pH?

p H = x

What membrane junction would u expect b/w cardiac cells

Gap junctions

what are the differences b/w luminal and basolateral membrane

luminal membrane faces the interior of a hollow organ /tube whereas the baso lateral membrane face the outside of the cell and usually faces the basement membrane

What are the classes of cells ?

Muscle;

nervous/neural;

epithelial;

connective

What is the basic role of the muscle cells?

to contract and generate force

what are the subclasses of muscle cells?

skeletal and cardiac (both striated) and smooth

Fast twitch

respond quickly to signals to contrast but are less resistant to fatigue

Slow twitch

Slower to contract but are more resistant to fatigue. you find these Fibres in muscles that don't require a fast contract response BUT do require "holding" of contraction for longer period of time

Slow Oxidative fibers

slow twitch fibres that require O2 ( resistant to fatigue but only w/ maintenance of O 2 delivery

Fast GlgcoIytic fibers

fast twitch fibres that can contract w/o O 2 ( anerobically ) they fatigue quickly since anarabic glycolysis does not produce a lot of energy (ATP) to maintain contraction.

Fast Oxidative Glycolytic fibres

fast twitch fibres that can run w/O2 or glycolytictally w/o O 2 = moderate resistance to fatigue → less ATP produced than SO fibres.

skeletal muscle subclasses

FOG, SO, FG

Differences of cardiac and skeletal muscle Cells

fibres not in tight parallel structure, cardiac are smaller, each cell is seperated by intercalated discs (desmosomes ) membrane junctions that hold the CelI together → cell comms

which class of lipoproteins transports cholesterol to the liver for excretion and which one \n transports cholesterol to the tissues?

HDL transport cholesterol to the liver for excretion; LDL transport cholesterol to the tissues

What is the difference between saturated and unsaturated fatty acids?

Saturated fatty acids have the carbons joined with single bonds while unsaturated have \n double bonds between the carbons

What determines the direction in which net diffusion of a nonpolar molecule will occur?

The concentration gradient of the molecule will determine which direction the molecule will \n move – will move from an area of high concentration to an area of low concentration + the \n charge of the molecule will also play a role in movement : a + ion will move in the direction of \n net – charge while a – ion will move in the direction of net + charge = electrochemical gradient

Describe the mechanism by which a mediated-transport protein moves a solute from one side \n of a membrane to the other

Mediated transport uses transporter proteins to move molecules across the bilayer. The \n molecule to be moved across the bilayer must bind to the transporter and the transporter must \n change shape to move the molecule across the membrane

What characteristics distinguish diffusion from facilitated diffusion?

Diffusion is simple movement of a molecule across it’s concentration gradient. Facilitated \n diffusion relies on the binding of a molecule to a transporter/carrier protein to be moved across \n the membrane across it’s concentration gradient

What characteristics distinguish facilitated diffusion from active transport?

Active transport requires the use of ATP to power the movement of molecules, usually against \n their concentration gradient while facilitated diffusion transports molecules across their \n concentration gradient

Contrast the mechanism by which energy is coupled to a transport protein during (a) primary \n active transport and (b) secondary active transport

Primary active transport = direct use of energy to move a molecule; secondary active transport \n doesn’t’ use ATP to move a molecule but uses the concentration gradient of a specific ion (does \n use ATP/energy indirectly to restore the ion to it’s normal resting location)

Describe the direction in which sodium ions and a transported solute move during co-transport \n and counter-transport

Co-transport = ion and molecule move in the same direction; Counter-transport = ion and \n molecule move in opposite directions

What change in cell volume will occur when a cell is placed in a hypotonic solution? In a \n hypertonic solution?

Hypotonic = higher water concentration in the solution than inside the cell, therefore water \n will move into the cell and the cell will swell and the volume will increase (cell volume = greater \n than 1.00). Hypertonic = lower water concentration in the solution than inside the cell so water \n will move out of the cell and the cell will shrink (cell volume = less than 1.00)

By what mechanism does the active transport of sodium lead to osmotic flow of water across \n an epithelium?

water always follows sodium (because a high sodium concentration is equivalent to a low \n water concentration and a low sodium concentration is equivalent to a high water concentration – \n there is always 2 concentration gradients when looking at water and salt – a gradient for the \n salt/sodium and a gradient for the water) if the membrane allows the movement of both, so \n movement of sodium into or out of a cell will result in the same direction of water flow

What is the difference between endocytosis and exocytosis?

Endocytosis moves molecules into or through a cell and exocytosis moves molecules out of a \n cell

If a cell was placed in a hypotonic solution, what would you expect would happen to the cell \n volume?

The cell volume would increase (cell would swell) if the cell was placed in a hypotonic \n solution

If the H ion concentration in blood is 1x10^-x mol/L, what would be the pH of the blood?

The pH of the blood would be x

What cell types would be expected to have GAP junctions between the cells?

Electrically active cells, such as the cardiac cells, tend to have gap junctions between the \n cells for fast transmission of signals

Epithelial cells have 2 different membrane surfaces. Which membrane surface faces the \n interior of the hollow organ or tubes lines by epithelial cells?

The luminal membrane

Which molecule will move best across a membrane – a lipid-soluble molecule or a lipid- \n insoluble molecule?

A lipid-soluble molecule

What is the basic role of the nervous/neural cells?

initiating and transmitting electrical signals for the relay of information through the body

What is the basic role of the epithelial cells?

regulate the movement of molecules in and out of organs and tissues

Skeletal muscle contraction pathway is what?

CNS signal -> motor neuron activation → Acetylcholine released from neural axon terminals → Binds to receptors on the skeletal muscle fibre plasma membrane → Initiates contraction

Smooth muscle contraction activation

spontaneous electrical activity initiated by pacemaker cells, nerves and hormones, local factors and changes to smooth muscle fibre environment

Body fluid pH vs blood pH vs intracellular fluids

most body fluids are in the pH range of 6.8-7.8 with intracellular fluids ranging from 7.0-7.2 and blood pH ranging from 7.35-7.45

A solution with a H+ ion concentration of 10^-6 mol/L

pH of 6

Cardiac activation/contraction

through pacemaker cells that spontaneously set the rhythm of contraction and relaxation (although hormones and neurotransmitters can alter that rate)

smooth muscle subclasses – single-unit versus multi-unit

single-unit smooth muscle:

                        - all cells/fibres in a group work together with a single activating event

            multi-unit smooth muscle:

                        - each cell/fibre must be activated separately

What atom is essential for the production of hemoglobin?

Iron

How many oxygen molecules can one hemoglobin complex bind?

4

Which blood cells are the most numerous?

Erythrocytes (RBCs)

What are the roles of the different classes of white blood cells?

Granulocytes: neutrophils = inflammation and bacterial destruction; eosinophils = \n parasite destruction and decrease allergic reactions; basophils = histamine \n release/inflammation. Agranulocytes: monocytes = macrophages = phagocytic cells; \n megakaryocytes = platelets = blood clotting; lymphocytes = T and B cells = specific \n immune responses

Where are the red blood cells/erythrocytes formed?

The RBCs are formed in the bone marrow but are final maturation occurs in the blood \n stream

All blood cells are formed from a single progenitor cell but that progenitor produces 2 \n different lines of blood cells that then differentiate into all the types of blood cells. Summarize \n the 2 pathways for the production of all the blood cells

The lymphoid stem cell line produces the T and B cells. The myeloid stem cell line \n produces the eosinophils, basophils, macrophages, neutrophils, platelets and red blood \n cells

What hormone stimulates red blood cell production? What system/organ secretes this \n hormone?

The hormone that stimulates red blood cell production is erythropoietin and it is produced \n and secreted by the kidneys

What hormone stimulates the production of the platelets?

The hormone thrombopoietin stimulates the production of the platelets from the \n megakaryocytes

A person with type A blood would have what antigens on their red blood cells and what \n antibodies in their plasma?

Type A blood means the person carries the A antigen on the surface of their red blood \n cells and also carry anti-B antibodies in their plasma

What reactions can occur with incorrectly typed blood transfusions?

For incorrectly typed blood transfusions, the following can occur: (i) the antibodies \n carried in the plasma of the donated blood can react and destroy the patient’s blood cells \n and (ii) the antibodies in the patient’s plasma can react with and destroy the donated \n blood cells

Mammalian cell membrane

Semi permeable aka Only some substances can pass thru the membrane and that many molecules need to be helped across the membrane

Diffusion

movement of molecules from a region of high concentration to a region of low concentration which over time will result in an equal distribution of molecules in solution

Osmosis

diffusion of H2O from an area of high water concentration to an area of low water concentration ( the presence of aquaporin is required )

flux

what we call diffusion