Cell Ultrastructure and Cytoskeleton Flashcards
Gel like material made of 70-85% water; electrolytes, proteins, lipids, carbs
protoplasm
Semi-liquid contents between cell membrane & nuclear membrane, surrounds organelles
cytoplasm
Semi-liquid contents within nucleus
nucleoplasm
DNA complexed with nucleoproteins
chromatin
Packaged chromatin
chromosomes
Segments of DNA coding for particular traits contained in chromosomes
genes
Different forms of same gene
alleles
Sorting of chromosome pairs according to size & shape
karyotyping
Electron-dense, darkly-staining, inactive DNA & nucleoproteins
heterochromatin
dispersed DNA active in transcription
euchromatin
Cells active in translation will have prominent ____ & abundant _____
nucleolus;euchromatin
Most of DNA-associated protein in eukaryotes; assist with DNA folding- chromatin organization into chromosomes
histones
segments of DNA wrap around several histones; regulate activity
nucleosomes
facilitates changing back and forth of euchromatin and heterochromatin
nucleoproteins
additional category of nucleoproteins; may also be involved in regulation of gene activity
non-histones
surrounds nucleus that separates nucleoplasm from cytoplasm
nuclear envelope
separates inner and outer membrane nuclear membrane
perinuclear cisterna
inner nuclear membrane associated with network of lamin filaments for support
nuclear lamina
70-80nm diameter channels surrounded by a ring of proteins that regulate exchange of macromolecules between nucleus and cytoplasm
nucleoporins
connect inner and outer nuclear membranes
nuclear pore complex
proteinaceous structures that contain rRNA; synthesized & assembled in nucleolus
ribosomes
powerhouse of the cell that produces ATP, site of oxidative phosphorylation and Kreb’s cycle
mitochondria
pleated inner membrane of mitochondria
cristae
Contains surface receptors for ribosomes and specializes in protein synthesis
rough ER
Function in lipid synthesis, transport of proteins to golgi, synthesis of cholesterol & steroid hormones, and is involved in detoxification & conjugation of drugs and toxins
smooth ER
Surround & coat proteins for transport, bud off sER, transport proteins between sER & golgi & between golgi and cell surface
coated vesicles
Complex of flattened, stacked, membrane-bound cisternae; functions in post-translational modification, packaging, & sorting of proteins synthesized in rER
golgi
Forming face; proteins arrive from rER in coated transfer vesicles; convex
cis golgi face
Maturing face; proteins packaged into clathrin-coated vesicles for secretion; concave
trans golgi face
during exocytosis and secretion, large amounts of intracellular membrane incorporated into outer cell membrane; recycled by golgi
membrane trafficking
membrane-bound vesicles containing hydrolytic enzymes; used to degrade organelles & cells with finite life spans during apoptosis
lysosomes
Type of endocytic vesicles with acid pH in lumen
endosomes
membrane-bound organelles containing oxidative enzymes (oxidases); found in liver and kidneys; use enzymes, free radicals, & hydrogen peroxide to oxidize toxic metabolites
peroxisomes
non-living components of the cell (fat droplets, lipids, glycogen)
inclusions
black, brown granular pigment produced by melanocytes and is transported to other cells
melanin
gold-brown granules; frequently seen in neurons; sometimes called old age pigment
lipufuscin
