lecture 1

Question 1

what comprises the cell membrane?

Answer 1

phospholipid bilayer, proteins, intercellular connections

Question 2

how is a phospholipid comprised?

Answer 2

glycerol backbone (hydrophilic) and two fatty acid tails (hydrophobic) and they are oriented so that the polar heads face opposing directions

Question 3

how does cholesterol help the membrane?

Answer 3

provides the membrane with rigidity and flexibility and can easily flip sides

Question 4

name the two types of proteins located in the cell membranes

Answer 4

integral proteins and peripheral proteins

Question 5

what are the functions of the integral protein?

Answer 5

1) anchored and imbedded through hydrophobic interactions
2) can span the membrane
3) include ion channels, transport proteins, receptors, guanosine 5’-triphosphate

Question 6

what are the functions of the peripheral protein?

Answer 6

1) not imbedded in the membrane
2) not covalently bound to membrane components
3) loosely attached to membrane via electrostatic interactions

Question 7

what are the other functions of proteins besides being pores?

Answer 7

they also aid in muscle contraction through which actin ties itself to anchoring protein via spectrin dimer

Question 8

what is used to bind actin to anchoring proteins?

Answer 8

spectrin dimers

Question 9

what happens if a baby is born without anchoring bridges that link protein to actin?

Answer 9

baby has trouble with activities that require muscle movements and cells begin to rupture and muscles atrophy

Question 10

what is hereditary spherocytosis?

Answer 10

spectrin is absent either not present or defective and leads to deformity of reb blood cells, the RBCs are not biconcave moreso rounded in nature, and so RBCs cannot maintain membrane integrity in addition to not being able to move through the capillaries

Question 11

what happens as a result of hereditary spherocytosis?

Answer 11

osmotic fragility (increased loss of RBCs) and increased work by spleen removing them from circulation

Question 12

signs/symptoms of hereditary spherocytosis?

Answer 12

fatigue

Question 13

what are the red blood cells called before becoming fully mature?

Answer 13

reticulocytes produced from the bone marrow

Question 14

what percentage of reticulocytes are comprised in the body? Percent with someone who has hereditary spherocytes? Why?

Answer 14

1%; 2-3.5%; reticulocytes keep puncturing because of their shape and the bone marrow works harder to replenish the loss of RBCs

Question 15

what is known as the powerhouse of the cell, site of ATP of production

Answer 15

mitochondria

Question 16

this cell component is responsible for the packaging and secreting of proteins?

Answer 16

golgi apparatus, keep in mind that it also modifies different parts of the cell like lysosomes to get rid of unwanted cellular material. If not able too, than developmental issues can affect the cell

Question 17

this part of cell is responsible for housing genetic material?

Answer 17

nucleus

Question 18

This part of the cell is used in the translation process to produce proteins

Answer 18

endoplasmic reticulum

Question 19

when proteins are produced using this pathway continuously and unregulated

Answer 19

constitutive pathway

Question 20

when proteins are produced in this pathway and secreted by a hormonal or neural signal

Answer 20

regulated pathway

Question 21

this is a type of vesicle found inside the cell that contains hydrolytic enzymes

Answer 21

lysosomes

Question 22

how does a cilium function?

Answer 22

comprised of microtubules and protein used to move them in unison. This is accomplished by dynein arms

Question 23

what happens if dynein arms are absent? what is this medical condition called?

Answer 23

if in the lungs, you have a defect in the dynein arms this can promote mucus buildup; Kartagener Syndrome

Question 24

what is kartagener syndrome?

Answer 24

a rare, ciliopathic, autosomal recessive genetic disorder that causes defects in the action of cilia lining the respiratory tract (lower and upper, sinuses, Eustachian tube, middle ear), fallopian tube, and flagella of sperm cells.

Question 25

where else can dynein arms be found?

Answer 25

along our axons containing a tubular system found in our neurons sending signals (NTs) to and from the brain via pathways using microtubules from cell to synaptic terminals using dynein and kinesin

Question 26

considering Kinesin is found along the axon, what direction does it travel.

Answer 26

it transports NTs from the body to the axonal terminal from the minus to plus direction

Question 27

also considering that dynein is found along the axon too, what direction does it travel?

Answer 27

it moves along the axon form the plus to minus end. It moves toward the cell body.

Question 28

Why is this particular dynein, found in the axon, important?Name one?

Answer 28

because if the animal bites, the virus is collected by the dynein and moved closer to the CNS. This causes the CNS problems; herpes, shingles

Question 29

What is Tay Sachs Disease?

Answer 29

fatal genetic lipid disorder where you have accumulation of ganglioside GM2 buildup in the nerves and brain. Caused by insufficient activity of enzyme beta-hexosamidase A found in Lysosomes to biodegrade acidic materials called gangliosides, made and biodegraded early in life. Some S/S include red retinas, muscle atrophy, paralysis, dementia

Question 30

What absent enzyme is responsible for Tay Sachs disease?

Answer 30

enzyme beta-hexosamidase A

Question 31

where is the mutation of the enzyme beta-hexosamidase A located that prevents it from being made?

Answer 31

The HEXA gene on the long (q) arm of chromosome 15 position 24.1

Question 32

what is Gaucher disease?

Answer 32

an autosomal recessive disease resulting in the accumulation of a fatty substance called glucocerebroside, a byproduct of the RBC cycling. Generally resulting from intermarrying from a small pool of genes

Question 33

what is the most prevalent lysosomal storage disorder

Answer 33

gaucher disease

Question 34

what absent enzyme is responsible for Gaucher disease?

Answer 34

glucocerebrosdiase

Question 35

the accumulation of this type of fatty acid is responsible for Gaucher Disease?

Answer 35

glucocerebroside

Question 36

name some S/S of Gaucher disease?

Answer 36

anemia, fatigue, easy bruising and bleeding; mild moderate and severe types and depending on type patient can asymptomatic and managing is possible. More neuro problems if severe

Question 37

what is endocytosis

Answer 37

taking in extracellular material into the cell either in small or big pieces and vesicles coated in clathrin to let cell know it is foreign

Question 38

name the different types of epithelial cells

Answer 38

tight junctions, gap junctions, adhering junction and desmosome

Question 39

what is tight junction?

Answer 39

form a watertight seal that block anything from in or out, found in the bladder, intestines, kidney

Question 40

what is desmosome?

Answer 40

join two cells at a single point and prevent fluid from circulating around sides of the cell and found in the skin or intestinal epithelium. Help cell to stay in place

Question 41

what is a gap junction?

Answer 41

small tunnels that connect cells facilitating movement of small molecules and ions between cells and found in smooth muscle allowing the fibers to contract as a unit, osteocytes

Question 42

what is an adhering junction ?

Answer 42

anchor cells together