Diversity of Cells and their Functions Flashcards
what is the most common stain used in histology and what does it consist of?
H+E
haematoxylin and eosin
what is haematoxylin and how does it stain?
basic die
stains acidic molecules purple i.e. nucleus, ribosomes
what is eosin and how does it stain?
acidic die
stains basic molecules pink e.g. proteins of the cytoplasm
what are the four basic tissue types?
epithelium
connective tissue
muscle
nervous tissue
what is the role of epithelium?
covers the body surfaces and lines hollow organs
how many kinds of muscle are there in the body?
three
what does nervous tissue consist of?
neurons and their supportive cells
what is a basal lamia?
a layer of extracellular matrix components at the basal surface of epithelia
how are epithelia supplied with nutrients and why?
diffuse across the basal lamina
non vascular tissue
name an organ formed by epithelial tissue
the liver
name the six major function of epithelia
mechanical barrier chemical barrier absorption secretion containment locomotion
name two minor functions of epithelia
sensation
contractility
what are the three types of epithelia classified by cell share?
squamous
cuboidal
columnar
describe squamous epithelia
flattened cells
describe cuboidal epithelia
cube shaped
height similar to width
describe columnar epithelia
tall and thin cells
what are the three types of epithelia classified by the number of layers?
simple
stratified
pseudo stratified
what is simple epithelia?
single layered
what is stratified epithelia?
two or more layers
what is pseudo stratified epithelia?
tissue appears to have multiple layers but in fact all cells are in contact with the basal lamina
what are goblet cells?
single cell mucous glands
what are the two types of glands?
endocrine
exocrine
describe endocrine glands
product secreted into blood
ductless glands
describe exocrine glands
product secreted into a lumen, a duct or onto the body surface
ducted glands
what are the three types of connective tissue?
soft
hard
blood and lymph
what are the two main components of connective tissue?
extracellular matrix
cells
what are fibroblasts?
cells that produce and maintain the extracellular matrix
what are adipose cells?
fat cells
what are osteocytes?
cells of bone
what are chondrocytes?
cells of cartilage
what are the three types of soft connective tissue?
loose
dense regular
dense irregular
describe loose soft connective tissue
loosely packed fibres
abundant ground substance
where is loose soft connective tissue found?
the mesentery
describe dense regular soft connective tissue
densely packed bundles of aligned collagen fibres
where is dense regular soft connective tissue found?
tendons
describe dense irregular soft connective tissue
densely packed bundles of collagen fibres running in many directions
where is dense irregular soft connective tissue found?
dermis of the skin
name the two types of hard connective tissue
cartilage
bone
what makes cartilage semi-rigid?
highly hydrated nature of the ground substance
how does cartilage receive nutrients?
avascular
from adjacent tissues by diffusion
what are the three types of cartilage?
hyaline
elastic
fibrocartilage
what is the most common type of cartilage?
hyaline
what are the two types of bone in a long bone?
cortical
cancellous/trabecular
what are Haversian canals?
small canals for blood vessels and nerves to pass through to supply bone
how is force produced in muscles?
by the movement of actin fibres over myosin fibres
what are the three types of muscle?
smooth
skeletal
cardiac
what are other names for smooth muscle?
involuntary
visceral
describe the structure of smooth muscle
no striations
elongated spindle shaped fibres
cigar shaped nucleus at the centre
why is smooth muscle involuntary?
not under conscious control
why is smooth muscle visceral?
predominantly found in organs
what are other names for skeletal muscle?
voluntary
striated
describe the structure of skeletal muscle
long fibres
many elongated nuclei at the periphery of the cell
what is the cell membrane of muscle cells called?
sarcolemma
describe the structure of cardiac muscle
striated
shorter
single nucleus at the centre
what is the connective tissue coat around nervous tissue called in the CNS?
meninges
what is the connective tissue coat around nervous tissue called in the PNS?
epineurium
what are the three types of neurone?
multipolar
bipolar
pseudo unipolar
what is the most common type of neurone?
multipolar
describe a multipolar neurone
many dendrites and one axon
describe a bipolar neurone
one dendrite and one axon
describe a pseudo unipolar neurone
short process gives rise to an axon in both directions
what are the there principle glia of the CNS?
astrocytes
oligodendrocytes
microglia
what do oligodendrocytes do?
produce myelin in the brain and spinal cord
what do microglia do?
provide immune surveillance
what is the principle glia of the PNS?
Schwann cell
what do Schwann cells do?
produce myelin in the PNS