biochem 7B - clinical correlates

Question 1

what cells synthesize bones

Answer 1

osteoblasts

Question 2

how does osteoblasts function

Answer 2

transport Ca2+ ions from blood into a secreted, uncalficied osteoid matrix composed of mostly type 1 collagen

Question 3

what type of collagen is osteoblasts made out of

Answer 3

type 1 collagen

Question 4

bone is restored by

Answer 4

osteoclasts

Question 5

enamel is made by

Answer 5

ameloblasts

Question 6

dentin is made by

Answer 6

odontoblasts

Question 7

cementum is made by

Answer 7

cementoblasts

Question 8

dentin and cementum are calcified over ___ like bone

Answer 8

type 1 collagen fibers

Question 9

what does the periodontium comprise of

Answer 9

gingiva, cementum, periodontal ligament, and surrounding alveolar bone

Question 10

what energy pathway do microbes rely on for their sole energy source

Answer 10

fermentation

Question 11

dental caries results from microbial fermentations that produce what and how

Answer 11

lactacte by glycolysis from monosaccharides

Question 12

what does saccharolytic mean

Answer 12

sugar metabolizing

Question 13

what is sugar metabolizing bacteria

Answer 13

saccharolytic bacteria
(lowers pH)

Question 14

what is non sugar metabolizing bacteria

Answer 14

asaccharolytic bacteria

Question 15

how do assccharolytic bacteria work

Answer 15

hydrolzye proteins and utlize amino acids for energy
(raises pH)

Question 16

oral microbiota is predominantly what type of bacteria and what is the end product

Answer 16

saccharolytic bacteria
lactic acid

Question 17

what are teeth adherent bacterial biofilms called and what are they responsible form

Answer 17

plaque
periodontal disease, and dental caries

Question 18

in people who keep their teeth clean and have no periodontal disease, the bacteria in a biofilm (microbiota) is mostly which gram type

Answer 18

gram positive
(resembles that in saliva or adhering to the oral mucosa)

Question 19

which gram bacteria has a thin peptidoglycan wall

Answer 19

gram negative

Question 20

where is mucins found and what is it

Answer 20

whole saliva contains mucins
(proteins covered w numerous saccharide [glycan] residues)

Question 21

how are gram positive bacteria able to tolerate the low pH by lactic acid production (which causes caries by dissolving tooth and enamel and dentin)

Answer 21

due to the thick cell wall

Question 22

what does gingival crevicular fluid provide (GCF)

Answer 22

this exudate of serum proteins provides a gingival sulcus that is rich in proteins than saliva and an environment that is more suited for an asaccharoyltic microbiota

Question 23

assaccharolytic bacteria produce

Answer 23

ammonia

Question 24

asaccharolytic bacteria secretes what that digest proteins to small peptides, which they digest (ferment)

Answer 24

proteases

Question 25

what happens to amino acids in asaccharolytic fermentation

Answer 25

amino acids are deaminated to ammonia

Question 26

ammonia accumulates from asaccharolytic fermentations, and this does what to the pH

Answer 26

makes the gingival sulcus alkaline
this high pH prevents caries from developing beneath the gingival sulcus

Question 27

what causes dental calculus and what does it do

Answer 27

alkaline environment also precipitates calcium and phosphate ions from GCF, causing dental calculus
dental calculus interfeeres w self-administed oral hygiene and assacharolytic metabolism intensifies

Question 28

when sulfur-containing amino acids (cysteine and methionine) and metabolized, what do they release

Answer 28

H2S along w ammonia

Question 29

what is the major contributor of oral malodor

Answer 29

H2S (often accompanies moderate to severe periodontal disease)

Question 30

saccharolytic bacteria are associated with what

Answer 30

dental caries and lactic acid production

Question 31

asaccharolytic bacteria are associated w what

Answer 31

perodontal disease

Question 32

collagen synthesis and degradation are central to the well-being of what parts

Answer 32

teeth and periodontium

Question 33

fibrillar colagen is syntehsized by

Answer 33

fibroblasts (extracellular matrix)
chondroblasts (cartilage)
osteoblasts (bone)
odontoblasts (dentin)
cementoblasts (cementum)

Question 34

what is the only calcified tissue that does not contain collagen in the vertebrate body

Answer 34

enamel

Question 35

what is collagen composed of

Answer 35

1/3 glycine
proline, hydroxyproline

Question 36

what are the sulfur containing aa

Answer 36

cysteine and methionine