MI final exam

Question 1

Medical interventions categories

Answer 1

Genetics
Diagnostics
Pharmacology
Surgery
Immunology
Medical devices
Rehabilitation

Question 2

How to find concentration of a solution

Answer 2

solute / (solute + solvent)

Question 3

How to find concentration of Tube 2

Answer 3

(concentration of Tube 1) * (tube dilution of Tube 2)

Question 4

ELISA basic steps

Answer 4

1) Insert sample, which (supposedly) contains antigen; antigen binds to well walls
2) Wash out unbound proteins
3) Insert primary antibody - if the antigen is present, the primary antibody will bind
4) Wash out unbound primary antibodies
5) Insert enzyme-linked secondary antibody - if the primary antibody (and by extension, the antigen) is still present, the 2nd antibody will bind to it
6) Wash out unbound secondary antibodies
7) Add enzyme substrate (TMB)
8) Observe color change

Question 5

Bacterial meningitis physiological effects

Answer 5

The pathogen causes inflammation of the meninges (membranes) around the brain and spinal cord, invoking symptoms like stiff neck, lethargy, fever, headache, and vomiting

Question 6

Gram positive bacteria

Answer 6

Stains purple (absorbs dye)
Thick layers of peptidoglycan
Lacks outer membrane

Question 7

Gram negative bacteria

Answer 7

Stains pink (doesn’t retain dye)
Thinner peptidoglycan layers
Outer membrane that protects it from antibiotic penetration

Question 8

Penicillins (beta-lactams) function

Answer 8

Inhibit peptidoglycan production (occurs in the call wall) -> inner membrane bursts due to osmotic pressure

Question 9

Efflux

Answer 9

Antibiotics enter through porin, but an efflux pump continuously pumps out the antibiotics so there is not a high enough concentration to cause cellular damage

Question 10

E. Coli I

Answer 10

Streptomycin-resistant
Chromosomal DNA

Question 11

E. Coli II

Answer 11

Ampicillin-resistant
Plasmid DNA

Question 12

Tetracyclines function

Answer 12

Inhibit DNA translation by preventing tRNAs from binding to ribosomes
(occurs in cytoplasmic ribosomes)

Question 13

Fluoroquinolones function

Answer 13

Inhibit DNA replication
Occurs in nucleoid region
Prevents topoisomerases (gyrases) from functioning in replication

Question 14

Sulfonamids function

Answer 14

Inhibit folic acid synthesis
Occurs in mitochondria
Bacteria aren’t killed, but they can’t multiply

Question 15

G+ cell structure (outer->inner)

Answer 15

Capsule (thinner)
Cell wall
Cell membrane
Cytoplasm
Nucleoid

Question 16

G- cell structure (outer->inner)

Answer 16

Capsule (thicker)
Outer membrane (unique to G- and contains endotoxins)
Cell wall
Cell membrane
Cytoplasm
Nucleoid

Question 17

PGD

Answer 17

Preimplantation genetic diagnosis - must be used with IVF to determine a genetic condition before an embryo is implanted in the uterus

Single cell is removed from an embryo and examined; parents/doctors can choose which embryo to implant

Egg + sperm combine to form a blastocyst, whose DNA/chromosomes are then examined

Question 18

Amniocentesis

Answer 18

Weeks 14-20
Needle inserted through abdomen to uterus
Sample is of amniotic fluid (liquid that cushions and surrounds the amniotic sac), which contains fetal cells
Can detect neural tube defects

Question 19

CVS

Answer 19

Weeks 10-12
2 options- catheter through cervix or needle through abdomen
Sample is from chorionic villus cells (from the placenta, whose DNA is the same as the fetus’ DNA)
Cannot detect neural tube defects

Question 20

PCR temperatures

Answer 20

Denature- 94 to 96 deg. C
Anneal- 50 to 65 deg. C
Extend- 72 deg. C

Question 21

Protein folding rules

Answer 21

1) Hydrophobic/nonpolar on the inside
2) Hydrophilic/polar on the outside
3) Acidic and basic side chains are on the protein surface and form salt bridges with each other
4) Cysteine sidechains are opposite each other -> covalent disulfide bond that stabilizes the protein

Question 22

Buffer order (highest to lowest salt)

Answer 22

Binding, wash, elution/TE
Hydrophilic = low salt
Hydrophobic = high salt

Question 23

Pathway of sound through the ear

Answer 23

Pinna (outer ear) -> auditory canal -> tympanic membrane (eardrum) vibrates -> sound is converted into mechanical waves -> ossicles (malleus, incus, stapes) vibrate -> oval window vibrates -> fluid in cochlea vibrates -> cochlear nerve

Question 24

Conductive vs sensorineural HL

Answer 24

Conductive: outer/middle ear is damaged, quieter sounds/unable to hear soft sounds
Sensorineural: inner ear is damaged, much harder to correct

Question 25

Similar pathogen vaccine

Answer 25

Live Collect copies of a pathogen that's similar to the target pathogen and separate the virus from other materials using a purifier; inject the vaccine

Question 26

Attenuated vaccine

Answer 26

Live Create a new strain of the target virus and over generations, select only the viruses that reproduce most at low temperatures so that they aren't active in the human body

Question 27

Killed vaccine

Answer 27

Inactive Grow copies of the target virus but inactivate it through formaldehyde, heat, or radiation

Question 28

Toxoid vaccine

Answer 28

Inactive Isolate the toxins of the target virus and neutralize them with aluminum salts or formaldehyde, and fill an adjuvant

Question 29

Subunit vaccine

Answer 29

Inactive Extract a piece of viral DNA that produces viral antigens, add that DNA to a yeast cell so that the yeast will also produce those antigens, and isolate the antigens for use in the vaccine

Question 30

Naked DNA vsccine

Answer 30

Inactive Use PCR to make many copies of one gene, splice a gene into a vector like a plasmid, produce copies of the vector through bacterial hosts, and isolate vectors (with detergent to lyse them) for use in the vaccine

Question 31

Rinne test/normal conduction

Answer 31

Place the tuning fork on the mastoid process, and when the patient can no longer hear it, put the opposite end to their ear canal. Air conduction should be twice as long as bone conduction

Question 32

Types of genetic testing/screening

Answer 32

Carrier screening PGD (preimplantation genetic diagnosis) - detects problems in blastocytes in IVF Fetal screening - includes CVS, amniocentesis, and ultrasounds Newborn screening - all newborns are screened for a standard list of disorders

Question 33

Dysplasia vs hyperplasia vs carcinoma in situ

Answer 33

Dysplasia = more cells than usual, loss of usual organization (can be malignant) Hyperplasia = benign overgrowth of cells Carcinoma in situ = severe dysplasia, can become cancer

Question 34

Pyrimidine antagonist

Answer 34

Synthetic drugs that block the synthesis of purine nucleotides like ATP, killing cancer cells

Question 35

5-FU mechanism

Answer 35

Inhibits dTMP, which is essential to DNA replication and repair