unit 3 Flashcards
cytology
study of cells
levels of organization
chemical, organelle, cellular, tissue, organ, organ system, organism
cell
smallest structure capable of all characteristics of life
cell theory
all organisms are made of cells, cells are smallest units of life, structure and functions or organism is because of cell activity, cells originate from preexisting cells (common ancestor), all cells have chemical and metabolic similarities
squamous
thin flat scaly shape, bulge where nucleus is, lines esophagus, airs of lungs, and epidermis of skin
cuboidal
squarish looking, liver cells
columnar
taller than wide, inner lining cells of stomach and intestines
polygonal
irregularly angular shapes with 4 or more sides (honeycomb), densely packed
stellate
multiple pointed processes, starlike shape, nerve cells
spheroid
round to oval, egg cells or white blood cells
discoid
disc shape, red blood cells
fusiform
spindle shape with thick middle and tapered ends, muscle cells
fibrous
long slender, skeletal muscles, axons (nerve fibers) of nerve cells
plasma (cell) membrane
outer boundary of cells, intracellular and extracellular region, communication between cells, regulating entry and exit of materials
intracellular
inside cell
extracellular
outside cell
cytoplasm
all material inside the cell. Cytosol & organelles
cytosol
fluid part of cell, 90% water
organelles
little organs, specific functions most have membranes
membranous organelles
membrane surrounding organelles
nucleus
control center, largest, contains dna
structure of nucleus
nuclear envelope, multinucleate (only in some cells), nucleolus, nucleoplasm
nuclear envelope
membrane around nucleus contains nuclear pores
nuclear pores
allows entry and exit of materials in nucleus
multinucleate
multiple nucleus
anuclear
no nucleus
nucleolus
region inside of nucleus that makes ribosomes
nucleoplasm
watery material inside cell
mitochondria
makes energy, preforms cellular respiration, liver and muscle cells b/c need a lot of energy to function
cellular respiration
glucose + o2 –> co2 + h2o + atp
matrix
fluid portion of mitochondria
inner membrane
membrane on the inside, includes cristae
cristae
folds in the membrane
outer membrane
membrane on the outside
lysosome
autophagy, apoptosis, catalyzes glycogen into glucose in liver cells, destroys engulfed pathogens
autophagy
cell destroys unwanted cellular materials
apoptosis
cell suicide, cell destroys itself
examples of unwanted materials in autophagy
chemicals, proteins, fat, worn out organelles, in WBC bacteria and viruses
examples of apoptosis
uterus cells after giving birth since they are no longer needed, cells of embryo/fetus (the cells that form webs between fingers and toes)
lysosome structure
digestive enzymes to catabolize organic compounds & highly acidic
peroxisome
destroys only certain substance, free radicals, hydrogen peroxide, some fats. in kidney where substances are destroyed
ribosome
protein synthesis, free floating in cytoplasm, attached to rough ER
ribosome structure
not membranous organelle, smallest organelle, rRNA
endoplasmic reticulum (ER)
channel extending from nucleus through cytoplasm, 2 types
rough ER
ribosomes, processes new proteins (changes it, ex: adding carb to make glycoprotein), helps protein get tertiary/quaternary structure, sends most proteins to Golgi complex in vesicles. in WBC and digestive glands ( they secrete a lot of proteins)
smooth ER
no ribosomes, makes some fatty acids (estrogen, testosterone), degrades chemicals in liver, stores and releases Ca in skeletal and cardiac muscles. In liver, muscle, gland cells ( ovary, testes)
Golgi complex
channel in cytoplasm, modification of proteins, sorts packages and ships proteins in vesicles, forms lysosomes
cytoskeleton
not membranous organelle, network of protein filaments throughout cytoplasm
3 types of filaments
microfilaments, intermediate filaments, microtubules
microfilament
smallest filament, made of actin, muscle contraction and movement of entire cells, during mitosis forms contractile ring that helps cytoplasm of cell separate, stabilizes cell membrane and microvilli, maintains cell shape,
intermediate filaments
found in places of mechanical/physical stress, anchors organelles in place, located in specific fixed position, for cell junctions
cell junctions
place where cells meet eachother
microtubules
largest filament, made of tubulin, hollow, maintain cell shape, intracellular movement, form cilia & flagella, form mitotic spindle
centrosome
near nucleus, microtubule organizing center, forms microtubules to make spindles. contains centrioles
centrioles
barrel shaped made of microtubules
cellular projections
of cell surface, only on certain cells, two types on formed by cell membrane other by cytoskeleton
microvilli
projections, formed by cell membrane. finger like, made of microfilaments, increase surface area of cell membrane for absorption, intestines & kidney (absorption of material takes place)
cilia
projections, formed by cytoskeleton, short hair like, move extracellular material across cell, cell lining of trachea (sweep mucus), oviduct (sweep egg down to uterus), inner ear (bending in response to vibration)
flagella
projections, formed by cytoskeleton, whip like. tail made of microtubules, movement of entire cell, sperm cell
tay-sachs
lysosome defective in brain cells, so brain cells cannot degrade certain lipids, lipids accumulates and causes damage.
some arthritis
in cartilage cells in joints lysosomes rupture and releases digestive enzymes which destroys cells and surrounding tissues
muscular dystrophy
mitochondria defective in muscle cells –> cannot make energy –> cells die overtime –>all muscles including heart die
some forms of Alzheimers
mitochondria defecting in braincells–> cannot make energy –> cells die overtime –> loss of brain function
antibiotics
some disrupt function of cell membrane and ribosome in bacteria cells only
cyanide
prevents mitochondria from making energy
poisonous mushrooms
prevent ribosome from making proteins
