quiz 2 cards Flashcards
major constituent of CT
ECM
ECM
protein fibers (collagen or elastic) and ground substance (glycans)
in ALL connective tissue, ECM _
is more abundant than cells
macrophages
breakdown of ECM
mast cells in loose CT
often near small blood vessels
fibrillar collagens
type I, II, and III
type I collagen fibers
synthesized by fibroblasts and osteoblasts; in tendons, organ capsules, dermis, bone
type IV collagen
synthesized by epithelial cells; used for filtration, found in basal laminae
type II collagen
synthesized by chondroblasts; found in cartilage
type III collagen
reticular collagen synthesized by fibroblasts; used in liver, bone marrow, lymphoid organs
collagen formation
RER makes procollagen-alpha chains –> form triple helix –> cleaved to procollagen –> cleaved to tropocollagen –> formation into fibrils –> fibers
elastic fibers
in arteries and stroma of lungs
reticular fibers
type III collagen
where does exchange in CT take place?
ground substance
loose CT
little collagen (type III), many cells & GS; supports microvasculature, nerves, and immune cells
dense irregular CT
lots of collagen (type I), few cells & GS; protects and supports organs
dense regular CT
mostly collagen (type I); provides connection with musculoskeletal system (tendons, ligaments, aponeuroses)
carcinomas
epithelial origin
sarcomas
mesenchymal origin
scurvy
lack of vitamin C prevents hydroxylation of proline or lysine, preventing collagen formation
scurvy symptoms
mouth sores, bruising, rashes, fatigue
Marfan syndrome
defective fibrillin synthesis, causing proteoglycans to replace elastic lamellae
Marfan syndrome symptoms
long body and limbs, aortic dissection is common
nonpolar amino acids
methionine, alanine, valine, leucine, isoleucine, proline
acidic amino acids
aspartate and glutamate
aspartate
Asp, D
glutamate
Glu, E
basic amino acids
lysine and arginine
polar amino acids
serine, threonine, cysteine, asparagine, glutamine, histidine
asparagine
Asn, N
glutamine
Gln, Q
aromatic amino acids
phenylalanine, tryptophan, tyrosine
pH > pKa
deprotonated
pH < pKa
protonated
basic amino acid in hydrophobic region
will disrupt nonpolar environment –> will lose a proton to be neutral –> harder to add back proton –> pKa decreases
acidic amino acid in hydrophobic
will disrupt nonpolar environment –> gain proton to be neutral –> will be harder to remove that proton –> pKa increases
essential amino acids
threonine, phenylalanine, lysine, valine, arginine (infants), tryptophan, isoleucine, histidine, leucine
essential AA mnemonic
The French Man Keeps Very (Red) Wine In His Library
Kwashiorkor
protein deficiency
Kwashiorkor symptoms
malnutrition, edema, anemia, skin lesions, liver problems
Kwashiorkor vs. Marasmus
Marasmus is just calorie deficiency; you can be protein deficient without being calorie deficient and get Kwashiorkor; also, Marasmus has no edema just muscle wasting
carboxyl group pKa
around 2
amino group pKa
around 9
severe protein malnutrition
leads to hypoalbuminemia –>low serum albumin reduces capillary oncotic pressure, allowing fluid to leak into tissues –> edema
adjacent beta-sheets interact through
hydrogen bonds between the backbone amine and carbonyl groups
when two alpha helices stack together, interactions are stabilized by _
side chains of amino acids
why does proline break alpha helices?
doesn’t have a backbone NH –> proline can not form a hydrogen bond with the n-4 residue in the alpha helix
two classes of tertiary structure
fibrous or globular
Ehlers-Danlos syndrome
collagen defects
Ehlers-Danlos symtpoms
stretchy skin, loose joints, joint pain, weird scar formation
pH < pI
net positive
pH > pI
negative charge
