histo exam 1 Flashcards
what are functional units of living organisms?
cells (can differentiate to perform special functions)
what are anatomically discreet collections of tissues?
organs
what are the cells that make up the functional elements of an organ (main actors)?
parenchyma cells
what are the cells that makeup the structural framework of an organ (background tissue)?
stroma
what is fluid tissue, contained within vessels of circulatory system?
blood
what surrounds and supports other tissue?
connective tissue
what covers body surfaces, lines cavities, and forms glands?
epithelium
what contains specialized contractile cells responsible for movement?
muscle
what contains modified cells responsible for intracellular communication?
nervous tissue
what do you use to prevent tissue denaturation (37% formaldehyde)?
formalin
what type of stain stains blue, basic dye, stains acids (nuclei)
hematoxylin (basophilic - blue/ purple)
what type of stain stains red-pink, acidic dye, stains bases (proteins)?
eosin (eosinophilic - red/ pink)
what functions as a semi-permeable membrane within a cell?
cell membrane (plasmalemma)
amphipathic (contains both hydrophilic and hydrophobic parts)
what does the hydrophilic portion of a cell contain?
positively charged N groups and charged phosphate groups
what does the hydrophobic portion of a cell contain?
two long chain fatty acids covalently linked to glycerol
what type of appearance does the cell membrane have?
tri-laminar (2 electron dense layers - phospholipid heads separated by electron lucent layer - FA tails)
how does the fluidity of a membrane change with increasing temperature?
fluidity increases with increasing temperature
how does the fluidity of a membrane change with decreasing of saturation of FA’s
high fluidity with lower saturation of FA’s
how does the fluidity of a membrane change with cholesterol levels?
higher amounts of cholesterol stiffens membrane (lower fluidity)
present in 1:1 ratio with phospholipids
what are proteins on surface of membrane termed?
extrinsic or peripheral
what are proteins incorporated within the membrane termed?
intrinsic or integral
what is another term for intrinsic proteins that extend from one side of the membrane to the other?
transmembrane proteins
what is the main difference between pores and channels in transmembrane proteins?
pores - always open
channels - can open and close
what type of membrane proteins involved in transport serves to transport ions across the membrane (Na+/ K+ pump)?
pumps
what type of membrane proteins involved in transport allows passage of water-soluble molecules via diffusion?
channels
what type of membrane proteins allow for cell recognition and binding on cell membrane (immune mediated reactions)?
receptor proteins
what type of membrane proteins initiate enzymatic reactions following binding with ligand molecules (hormone)?
transducers
what type of membrane proteins are components of ion pumps and digestive action?
enzymes
what type of membrane proteins add mechanical stability to membrane?
structural proteins
what two molecules help to makeup the glycocalyx?
glycoproteins and glycolipids
what are two functions of the glycocalyx?
protects surface of cell membrane
may be involved in cell recognition
(important in mediating exchange between internal and external environment)
what type of transport:
- occurs DOWN a conc or ionic gradient
- some agents can pass directly through cell membrane
- larger water-soluble molecules use pores or channels in transmembrane proteins
simple diffusion
what type of transport:
- passive and concentration dependent but requires carrier molecules
- also called carrier mediated diffusion
- reversible binding and unbinding to transport water-soluble hydrophilic molecules
facilitated diffusion
types of ion channels (transmembrane proteins)
ungated channels - always open (pores)
gated channels - open or closed (selective permeability)
voltage gating (requires change in membrane potential)
chemical gating (requires binding of signaling molecule)
how can passive and facilitated diffusion be enhanced?
increase in surface area of a cell membrane via folding
what type of channel allows water to cross plasma membrane faster than simple diffusion alone?
aquaporins
what type of transport:
- independent of concentration (usually against conc gradient)
- requires energy (ATP to ADP)
- occurs at specialized dynamic pore sites (usually transmembrane proteins)
active transport
what type of transport:
- requires energy
- engulfment of molecules or particles by cytoplasmic extensions
- result in membrane bound endocytic vacuoles (endosomes)
bulk (vesicular) transport
what are the two types of endocytosis?
phagocytosis - engulfment of solid particulate matter
pinocytosis - engulfment of liquids
what type of endocytosis requires extracellular molecules bind to receptor proteins (uses clathrin)?
receptor mediated endocytosis
any type of bulk transport or vesicular movement from cytoplasm to ECS
exocytosis
what term is used for transport of material across or through the cell via sequential endocytosis followed by exocytosis?
transcytosis
examples of prokaryotes and eukaryotes
prokaryotes - monera, cyanobacteria
eukaryotes - single celled protists, protozoa, multi celled metazoans
what makes up protoplasm?
70-85% water, electrolytes, proteins, lipids, and carbohydrates
what is the term for the semi-liquid contents between cell membrane and nuclear membrane, surrounds organelles?
cytoplasm / cytosol
nucleoplasm - within nucleus
what organelle contains the genome of DNA and makes up <20% of nuclear mass?
nucleus
what is the term for what is formed from DNA complexed with nucleoproteins?
chromatin
what is chromatin packaged into?
chromosomes
what are segments of DNA coding for particular traits?
genes
what is the term for different forms of the same gene?
alleles
how do chromosomes exist in most eukaryotic cells?
homologous pairs (diploid in humans - 2n = 46)
what is the term for sorting of chromosome pairs according to size and shape?
karyotyping
what type of chromatin is electron dense, darkly staining, inactive DNA and nucleoproteins?
heterochromatin
what type of chromatin is dispersed DNA active in transcription (RNA synthesis) and unravels to become visible as lamp brush chromosomes?
euchromatin
what is the term for a permanently inactive DNA (X chromosome) in females?
barr body
what will cells in active translation have?
prominent nucleolus and abundant euchromatin
in what state is most chromatin in the nucleus usually found?
heterochromatin… only a small % active at any one time as euchromatin (constantly changing with protein synthesis)
what is the term for most of DNA-associated protein in eukaryotes that help to assist in DNA folding and chromatin organization into chromosomes?
histones
what is the term for segments of DNA that wrap around several histones and regulate DNA activity?
nucleosomes
what is the term for additional category of nucleoproteins that may also be involved in regulation of gene activity?
non-histones
what separates the nucleoplasm from the cytoplasm?
nuclear envelope
how many layers make up the nuclear envelope and what separates them?
2 layers (inner and outer nuclear membrane)
separated by perinuclear cisterna
what type of filaments help to make up the nuclear lamina and provides support to the membrane?
lamin filaments
what are the inner and outer nuclear membranes connected by that contains nucleoproteins and allowed for communication between cytoplasm and nuceloplasm?
nuclear pore complex
what are the two subunits of ribosomes?
40S and 60S
where are ribosomes synthesized and found within a cell?
synthesized and assembled in nucleolus
found free in cytoplasm, attached to rER and outer nuclear membrane
often grouped together as polyribosomes or polysomes
what organelle is commonly termed the power house of the cell and why does it have this nickname?
mitochondria
site of Kreb’s cycle and oxidative phosphorylation
what two types of cells are mitochondria NOT present in?
red blood cells and keratinocytes
how many membranes do mitochondria have and which one is permeable?
2 membranes (inner and outer)
outer membrane is permeable and contains porin
which membrane of mitochondria is pleated to form folds that is lined with elementary particles that contain enzymes for oxidative phosphorylation?
inner membrane (folds = cristae)
inner cavity is filled with amorphous matrix
what organelle possesses circular DNA (maternally inherited) and are self replicating?
mitochondria
where does cell respiration begin and with what process?
occurs in cytoplasm
glycolysis which breaks down glucose into pyruvate
DOES NOT require oxygen
where does pyruvate then diffuse so that it can undergo aerobic respiration?
mitochondrial martix
during what process is most ATP produced by cytochromes of the ETC?
oxidative phosphorylation
what are the enzymes on the inner membrane of cristae?
cytochromes
what organelle is a series of membranous sheets and tubules throughout the cytoplasm?
endoplasmic reticulum
what type of ER has surface receptor molecules for ribosomal attachment and is the site for protein synthesis?
rough ER
what type of ER functions in lipid synthesis, transports proteins from rER to golgi, membrane formation / recycling, cholesterol / steroid hormones synthesis, and detoxification of drugs and toxins?
smooth ER
what is the term for the “little taxis” that surround and coat proteins for transport, bud off of sER, transport proteins between sER and golgi and between golgi and cell surface?
coated vesicles
what is the name of the organelle that functions in post-translational modification, packaging, and sorting of proteins synthesized in rER?
golgi apparatus
which face of the golgi is convex?
cis (forming face)
which face of the golgi is concave?
trans (maturing face)
how are proteins packaged into vesicles for secretion?
packaged into clathrin coated vesicles along the maturing face of the golgi
what is the name of the organelle that are membrane bound vesicles containing hydrolytic enzymes?
lysosomes
what is the term for newly formed lysosomes produced by rER and golgi (inactive form)?
1’ lysosomes (primary)
what is the term for primary lysosomes that fuse with phagocytic vesicles (phagosomes) and become active?
phagolysosomes (2’ lysosomes - secondary)
what is the term for lysosomes that are involved in hydrolytic breakdown?
3’ lysosomes or residual body
what is the term used to describe programmed cell death (aka autophagy)
apoptosis
what is the name of a membrane bound vesicle that is a type of endocytic vesicle with an acid pH in lumen (due to proton pumps in membrane)?
endosomes
what is the name of a membrane bound vesicle that contains oxidative enzymes (oxidases), catalase, and peroxidase?
peroxisomes
what do peroxisomes use to oxidize toxic metabolites?
enzymes, free radicals, hydrogen peroxide
what is the term for non-living components of a cell that include: neutral fat droplets, lipids, glycogen, secretory / pigment granules, and can also be viral?
inclusions
what is the name of the intracytoplasmic pigment that gives a black / brown granular pigment produced by melanocytes and is transporter to other cells?
melanin
what is the name of the intracytoplasmic pigment that gives a gold / brown granules and is frequently seen in neurons (sometimes called old age pigment)
lipofuscin
what are the four main functions of the cytoskeleton?
- provide structural support for membrane and organelles
- intracellular movement / transport of substances
- cell locomotion
- muscle contration
what are the three main elements of the cytoskeleton?
microfilaments, intermediate filaments, microtubules
what type of filament is important in maintaining cell shape and facilitating shape changes during movement?
mircofilaments (actin and myosin)
how are larger actin filaments made from the smaller g-actin subunits?
- smaller g-actin subunits polymerize to form protofilaments
- 2 protofilaments twist together to form a double helix (f-actin)
- these can then combine to form larger actin filaments
what protein does actin link with beneath the plasma membrane to form the cell cortex (terminal web)?
filamin
what function does the cell cortex serve?
prevents cell from deformation
what microfilament is classified as a motor protein along with dynein and kinesin?
myosin
what microfilament do myosin heads form cross bridges with between adjacent filaments?
actin filaments
what is required for movement of filaments for muscle contraction?
calcium and ATP
which type of filament is useful in immunohistochemistry and tumor ID?
intermediate filaments
which type of intermediate filament is a characteristic of all epithelial cells, found in the epidermis of skin and forms tonofibrils?
(cyto)keratin
which type of intermediate filament is found in medodermal cells of mesenchymal origin (includes endothelial cells, muscle and neutoectodermal cells)?
vimentin
which type of intermediate filament is unique to muscle cells and mesodermal in origin?
desmin
which type of intermediate filament is present in nerve cells (neurons)
neurofilament proteins
which type of intermediate filament is found in glial (support) cells of nervous system (astrocytes)
glial fibrillary acidic protein (GFAP)
which type of intermediate filament forms a layer on the inside of the nuclear membrane?
lamin
what type of filament is composed of alpha and beta tubulin (globular protein subunits) that are arranged in a coiled spiral pattern and polymerize to form hollow tubes?
microtubules
what type of filament is involved in cell movement, maintenance of cell shape, and intracellular transport of substances?
microtubules
how does movement occur when talking about microtubules?
addition or subtraction of tubulin subunits
what motor proteins attach microtubules to organelles and allow for movement in cytoplasm?
dynein and kynesin
what cell structures can we find microtubules in?
cilia and flagella
centrioles
basal bodies of cilia
mitotic spindles
why are drugs like colchicine, vincristine, and vinblastin used chemotherapy?
inhibit polymerization of microtubules and cell division
NOTE - drugs are nonspecific and can not tell a difference between cancer cell and regular cell (explains why cancer patients lose hair)
what cell structure has 9 pairs of microtubules (peripheral doublets) containing dynein arms arranged in circle with central doublet in middle (9 + 2 structure)
axoneme
how does the central doublet of an axoneme connect to peripheral doublets?
radial spokes
how to peripheral doublets connect to one another in axoneme?
nexin (protein)
in cilia, where does the axoneme grow from?
basal body derived from modified centriole
where are centrioles normally located within a cell and what do they function in?
located in region of cell called centrosome (near nucleus)
function in cell division
what does each centriole consist of?
9 triplets of microtubules arranged in a cylinder
what controls distribution of chromosomes in daughter cells that is made up of microtubules?
mitotic spindle
what are the five phases of mitosis?
interphase, prophase, metaphase, anaphase, telophase
what is the phase of the cell cycle that is considered the resting phase or time between divisions (occupies most of life of cell)?
interphase
what is the longest cell phase during which cell growth, maturation, and differentiation occur?
G1 (1st gap phase)
what are the two ways that growth of a tissue can occur?
hypertrophy - increase in cell size (occurs during G1)
hyperplasia - increase in cell number (occurs during mitosis)
what phase of the cell cycle does replication of DNA occur prior to division?
S phase
what is the chromosome number at the beginning and end of S phase (mitosis)?
beginning - 2n
end - 4n
prior to replication in S phase, each chromosome has a __ chromatid with attached centromere
single
following replication in S phase, each chromosome contains __ chromatids with attached centromere
two
during what cell phase does the cell prepare for mitosis and we see synthesis of ATP and tubulin for mitotic spindle?
G2 (2nd gap phase)
M phase of mitosis is characterized by what two divisions that result in 2 daughter cells?
karyokinesis - nuclear division
cytokinesis - cytoplasmic division
during what phases do chromosomes condense, become visible, and look like coiled snakes?
S and M phases
during what phases do chromosomes exist in an unraveled mess that are not readily visible?
G1 and G0 phases
what is the term for cells that retain capacity for division with proper stimulus after entering the G0 phase (reserve stem cells)?
facultative dividers
what the the term for cells that lost the capacity to divide after entering G0 phase (neurons, cardiac myocytes)?
terminally differentiated cells
during what phase of mitosis do cells become visible condensed, microfilaments and microtubules of cytoskeleton disaggregate, and centrioles migrate to poles of cell to form spinal apparatus?
prophase
during what phase of mitosis does the nuclear membrane and nucleoli disappear and the mitotic spindle attaches to chromosomes at kinetochore?
prometaphase (late prophase)
during what phase of mitosis do chromosomes line up along equator (metaphase plate)?
metaphase
during what phase of mitosis do centromeres split apart and chromosomes migrate to opposite ends of cell (pulled by microtubules connecting centriole and kinetochore)
anaphase
during what phase of mitosis does mitotic spindle disaggregate, nuclear envelope reassembles, nucleoli reappear, plasma membrane forms cleavage furrow and cytokinesis begins?
telophase
what is the term used to describe proportion of cells in a tissue in mitosis at any given time and why is it important
mitotic index
important in tumors - estimated by counting number of mitotic figures (normally <1)
what is the term used to describe the production of haploid gametes (eggs and sperm)
gametogenesis
name of gamete formation in males and females
males - spermatogenesis
females - oogenesis
what cell division process involves chromosomal duplication followed by two consecutive cell divisions to produce haploid gametes?
meiosis
what does the fusion of gametes (fertilization) produce?
diploid zygote (fertilized egg)
what are the two main differences in mitosis and meiosis I?
- during prophase I, homologous pairs of chromosomes form tetrads and exchange chromatin via crossing over (chiasmata formation)
- centromeres DO NOT split during anaphase I
NOTES TO MAKE ABOUT SECOND MEIOTIC DIVISION
- interkinesis - NO replication of DNA
- no crossing over during prophase II
- centromeres split during anaphase II
- cytokinesis yields four unique haploid gametes in telophase II
how many functional gametes are formed during gametogenesis within males and females?
males - 3 or 4 viable gametes
females - 1 functional gamete with 2-3 non-functional polar bodies
when does spermatogenesis and oogenesis begin in males and females?
males - beings at puberty
females - beings during fetal development
NOTE - female germ cells enter prophase I during 5th month of gestation and remain until ovulation (12-50 years later)
what is the term for a cell undergoing apoptosis where we see condensation of nuclear chromatin and shrinkage of the nucleus?
pyknosis
what are some characteristics that we can see from staining a cell that is undergoing apoptosis?
- nucleus becomes very small and darkly stained (pyknotic nucleus)
- cell swells as a result of influx of water due to loss of ATP to maintain Na+/ K+ pumps
- cytoplasm becomes bright pink (eosinophilic)
what is the term for chromatin in the nucleus beginning to degenerate during apoptosis?
karyolysis
what is a term for nuclear material beginning to fragment and nuclear membrane disintegration during apoptosis?
karyorhexis
what is another name for fragmented nuclear debris?
apoptotic bodies
what is the term for death of cells as a result is inflammation, traumatic injury, or pathology?
necrosis
plasma makes of how much of total blood volume?
55% of blood volume
what is the serum of blood made up of?
plasma minus clotting factors
what are three main functions of blood / blood stream?
- primary vehicle for transport of nutrients, O2, CO2, waste products and hormones
- thermoregulation
- maintenance of homeostasis
type of plasma protein that makes up the bulk of plasma proteins (all synthesized in liver), function as transport for proteins for insoluble metabolites, and are responsible for maintaining colloid osmotic pressure in blood vessels
albumins
type of plasma protein that are large molecules used as transport proteins for lipids and heavy metal ions (largest fraction - immunoglobins)
globulins
type of plasma protein that are the largest proteins, soluble, and synthesized in the liver… polymerize to form insoluble fibrin during clotting
fibrinogens
(prothrombin - thrombin catalyzes fibrinogen - fibrin)
what are the components of blood formed in bone marrow via hemopoiesis?
red blood cells
white blood cells
platelets
what is hematocrit?
volume of red blood cells
what is the term that describes genetic neoplasia (higher than normal rbc count)
polycythemia vera
what makes up the packed cell volume
hematocrit +/- buffy coat (depending on source)
what makes up the buffy coat?
white blood cells and platelets (1-2%)
what term describes the general process by which mature blood cells develop from precursor cells?
hemopoiesis
what term describes the process of red blood cell production?
erythropoiesis
what term describes the process of white blood cell production?
myeolpoiesis
hemopoiesis is under control by which hormone secreted by the kidney?
erythropoietin
how does the relationship of active sites of blood cell production relate to age?
number of active sites decreases with age
what is the difference between red and yellow bone marrow?
red marrow - active (contains large numbers of mature rbc’s)
yellow (fatty) marrow - inactive (adipose tissue gives yellow color)
stages of erythropoiesis (start to finish)
stem cell (CFU-E)
proerythroblast
erythroblst
normoblast
reticulocyte
mature rbc
what are the overall trends in erythropoiesis?
progressive decrease in cell size
loss of nucleus and organelles
increase in hemoglobin
what are some of the defining characteristics of rbc’s?
- no nucleus in mammals
- before released into blood stream - nucleus extruded and all organelles degenerate
- lack mitochondria (make ATP via glycolysis)
what is the term for occasional, basophilic nuclear remnants visible within cytoplasm?
Howell-Jolly bodies
what is the term for immature rbc’s with stippled cytoplasm, still have some rRNA and are slightly larger than mature rbc’s?
reticulocytes
what is the term for an increase number of reticulocytes in circulation associated with chronic blood loss, hemolytic anemia (aka left shift)?
reticulocytosis
vitamin B12 and B9 deficiency can lead to what?
large cells called macrocytes (delayed maturation of rbc’s)
what is the term for large numbers of erythrocyte precursors in peripheral blood?
megaloblastic anemia
what size are erythrocytes?
6-8 um diameter biconcave discs (allow for deformability)
what is the primary structural protein in rbc’s?
spectrin
transport of what gases are erythrocytes involved in?
O2 and CO2 exchange
contain large amounts of Fe containing pigment (hemoglobin)
what disease can occur from low levels of Fe or blood loss?
anemia
what are some characteristics of rbc’s if a person has Fe deficient anemia?
small (microcytic) and pale staining (hypochromic)
(normal rbc’s are normocytic and normochromic)
what disease is caused by a single amino acid substitution that causes a 3D change in structure of Hb molecule?
sickle cell anemia (causes these cells to be more fragile and easily damaged)
what is a term for small, non-nucleated cells containing organelles?
platlets (thrombocytes)
how are platelets formed?
formed from large, polyploid cells in bone marrow (megakaryocytes) which develop pleated demarcation channels in cytoplasm (platelets then tear off)
what is the term used to describe the result of cascade interaction between plasma proteins and coagulation factors?
coagulation
explain what the two convergent pathways of coagulation entail
extrinsic (faster) - initiated by release of tissue thromboplastin as a result of tissue damage
intrinsic (slower) - initiated by exposure of collagen (requires numerous clotting factors and is a longer cascade reaction)
what happens after the wall of a blood vessel breaks (think of both coagulation pathways)?
- releases thromboplastin (initiates extrinsic pathway)
- exposes collagen (initiates intrinsic pathway)
- platelets mechanically adhere to exposed collagen and release serotonin (vasoconstrictor)
at what point do the extrinsic and intrinsic pathways converge to form the common pathway for coagulation?
where factor X is activated
results in conversion of prothrombin to thrombin, converts soluble fibrinogen, into soluble fibrin
what are two anticoagulants?
antithrombin III and heparin
what is hemophilia a result of (present on X chromosome)?
deficiency in clotting factors so blood can’t clot (defect in intrinsic pathway)
how are leukocytes (WBC) able to leave circulation?
migration
pavementing (rolling and adhesion)
diapedesis
extravasation
how are leukocytes attracted to inflammatory sites?
chemotaxis via cytokines
how are white blood cells categorized (2 categories)?
granulocytes (possessing granules)
agranulocytes (lacking granules)
what type of granules do all WBC’s possess?
primary granules (stain blue/ purple - azurophilic granules)
what type of enzymes do primary granules contain?
lysosomal enzymes (acid hydrolases)
what type of granules do granulocytes possess?
primary and secondary granules
what are the three types of granulocytes?
neutrophils, basophils, and eosinophils
what type of granulocyte makes up 40-75% of WBC’s?
neutrophils
how many lobes does the nucleus of a neutrophil have?
3-5 lobes (polymorphonuclear cells)
what type of energy metabolism does neutrophils use?
primary anaerobic glycolysis
how do secondary granules stain in neutrophils?
either basophilic or eosinophilic (neutral)
which type of granulocyte contains inflammatory mediators, complement activators, proteases, defensins, lactoferrin, lysozoyme (actibacterial compounds) and are released during inflammatory reaction?
neutrophils
what do the tertiary granules of neutrophils contain?
gelatinase (breaks down collagen)
how long does acute inflammation last?
several days
how long does subacute inflammation last?
1 week to 10 days
how long does chronic inflammation last?
more than 10 days
which granulocyte is associated with acute inflammation (lasting several days)?
neutrophils
what are redness (rubor), swelling (tumor), heat (calore), and pain (et dolore) cardinal signs of?
inflammation
