Histology Flashcards
what is histology
study of tissues
what is tissue def
group of cells with similar struct;ure, function, and embryologic origin. or collection of cells and cell products that perform specific limited functions
what are the three germ layers
ectoderm
mesoderm
endoderm
what does ectoderm become
epithelium and nervous tissue
what does mesoderm become
muscle, connective tissue and epithelium tissue
what does endoderm become
epithelium tissue
what do all cells carry out?
complete dna insturctions for all body structures and functions
is the genome identical within an organism
yes (minus mutations)
what does it mean that cells are specialized
they are desinged for differenent functions
what does differentiation depend on
which genes are active and which are inactive
Active vs inactive (protein activity)
Active- proteins produced
Inactive- proteins suppressed
heterochromatin def
dna that is highly folded
this is linked to inactive genes
euchromatin def
dna that is less folded
this is linked to active genes
what are the 4 classes of tissues
epithelial
connective
muscle
nervous
epithelial tissue main function
line/protect surfaces
connective tissue main function
play a variable role in support
muscle tissue main function
to generate movement
nervous tissue main function
to communicate with electiricity
what layer does epithelial tissue form from
all 3 germ layers