Directions/Cell Cytology Flashcards
anatomical position
standing squarely on all four limbs with head and tail extended
ideal position for all directions
dorsal
toward the back
ventral
toward the belly
cranial or rostral
closer to the head along main body axis
caudal
closer to the tail along main body axis
median
the perfect plane
one unique longitudinal plane dividing the animal into EQUAL right and left halves
sagittal
longitudinal planes parallel to the median plane (infinite in number)
ipsilateral
on the same side
contralateral
on the opposite side
medial
towards the midline ie median plane
lateral
AWAY from the midline
superficial
towards the surface of the body or the surface of a solid organ
deep
away from or removed from the surface of the body
electron dense structures
parts appear darker on the image
electron lucent structures
parts appear lighter on the image
freeze fracture technique
fractures occur along cell membranes
basophilic stains
base loving —> will show acids on slide
appear BLUE or PURPLE
acidophilic stains
acid loving —> shows bases
will appear PINK, RED, or ORANGE
hematoxylin
basophilic stain (stains acids)
eosin
acidophilic stain (stains bases)
H & E
most common stain
periodic-acid schiff (pas)
stains carbs magenta or purple
trichrome
stains collagen fibers blue or green
artifacts
tissue shrinkage and lost molecules
something that is artificially made by people
dorsal plane
defines dorsal vs ventral ie top half of animal vs bottom half of animal
transverse plane
longitudinal planes perpendicular to the median and dorsal planes (infinite in number)
epithelium
covers, lines, secretes and absorbs substances
connective tissue
structural support
muscle
contracts to produce movement
nervous tissue
integrates sensory information with motor outcomes
cell
-basic structural/functional unit
unit membranes
selective barrier around cells and some organelles
-appears trilaminar under TEM
plasma membrane
E-face (outer leaflet) —> faces extracellular space
P-face (inner leaflet) —> faces cytoplasm
has peripheral and integral proteins
glycocalyx (sugar coat)
vesicular transport
transportation of material into or out of a cell by membrane-bound vesicles
REQUIRES ATP
exocytosis
-release of cellular products = secretion
1) material is packaged into secretory vesicles by the golgi apparatus
2) transported to plasma membrane
3) fuse with plasma membrane and releases into extracellular space
regulated secretion
vesicles congregate near plasma membrane
secretory granules = vesicles waiting for a signal
secretions condense
signaled release into extracellular space
constitutive secretion
CONTINUOUS secretion
no accumulation of secretory vesicles
no signaling required
ex: fibroblasts, plasma cells
endocytosis
=ABSORPTION
plasma membrane infolds to form vesicle containing inbound material —> vesicles fuse with lysosomes for processing
3 types
pinocytosis
cellular drinking
generalized type of absorption (all cells)
forms pinocytotic vesicles (caveolae)
fuse with lysosomes for processing
aids in membrane trafficking - recycling plasma membrane
phagocytosis
cellular eating
engulfing large particles, cell debris, bacteria
1) pseudopodia extend/surround the material
2) vesicles called phagosomes are formed
3) phagosomes fuse with lysosomes
4) lysosomes process/degrade/recycle the material
phagocytic cell characteristics
pesudopodia (irregular outline)
phagosomes, lysosomes, phagolysosomes
nucleus
nuclear envelope
nuclear pores
chromatin: DNA
nucleolus: rRNA
euchromatin
active transcription (DNA uncoiled) more electron lucent
heterochromatin
inactive (DNA condensed)
more electron dense
polyribosomes
free ribosomes
create cytoplasmic proteins –> proteins that are going to be used inside the cell
ER bound ribosomes
create membrane and secretory proteins, lysosomal enzymes
rough ER
interconnected, flattened membranous sacs for protein synthesis
outer surface: er bound ribosomes
inner surface: cisterna
proteins are synthesized into the cisterna and then transported to the golgi apparatus for packaging
golgi apparatus
interconnected, flattened sacs where proteins from rER are processed, sorted, packaged within cisterna
lysosomes
digestive compartments
spherical, membrane-enclosed
have varying electron densities —> due to different concentrations
contain enzymes that process/degrade lysosomal contents
FUSE WITH: autophagosomes, endocytotic vesicles, phagosomes
mitochondria
site of ATP synthesis
rod shaped
2 unit membranes: outer is smooth, inner is folded (forms cristae)
smooth ER
interconnected membrane-enclosed tubules (not sacs)
no ribosomes, no protein synthesis
abundant in cells that detoxify and secrete steroid hormones
present in all cells
cytoskeleton
cell morphology (shape) cell mobility interacts with extracellular matrix
components: actin, intermediate filament, microtubules
actin (thin filaments)
smallest diameter
function:
1) help anchor cells to each other and ECM
2) form structural core of microvilli, stereocilia
3) movement (contraction, extending processes)
intermediate filaments
larger than actin
function:
1) cell to cell adhesion
2) cell to ECM adhesion
high tensile strength
microtubules
largest cytoskeletal component
function:
1) provide rigidity to cell shape
2) aid intercellular transport
3) movement of cell, cilia, flagella
structural component of: centrioles, basal bodies, cilia
inclusions
in cytoplasm that are not dissolved and are not membrane bound
