Cells & Organelles

what is the nucleus

contains the cell DNA and coordinates cell activities such as protein synthesis and reproduction

where is genetic in prokaryotes stores

nucleoid

what is the nucleolus

site of ribosome (rRNA) synthesis

what is the cytoplasm

the fluid filled area in which the cell’s metabolic activities occur; also includes the organelles wa

what is the mitochondria

double layered, makes ATP, site of fatty acid catabolism. Has own circular DNA and ribosomes w

what are ribosomes

made of rRNA ; makes proteins w

what is the rough endoplasmic reticulum

has ribosomes attached to the structure. Functions to synthesize and store proteins

what is the smooth endoplasmic reticulum

functions to synthesize lipids and steroid hormones for export

what is the golgi apparatus

modifies and packages proteins (like glycosylate polypeptides)

what are lysosomes

made by the golgi

functions in apoptosis, and break down nutrients, bacteria, and cell debris wh

what are peroxisomes

common in the liver and kidney that function to breakdown substances

what is the cytoskeleton

maintains cell shape and movement

includes microtubules, intermediate filaments, and microfilaments

what are microtubules

composed of tubulin. Support cell and mobility for cell activities

what are examples of microtubules

centrioles, cilia, and flagella wha

what are centrioles

developments of spindle fibers for cell division

what are cilia

short hair like extensions from cell for movement

what are flagella

thread like extension from cell for movement

what are intermediate filaments

maintain cell shape

what are microfilaments

composed of actin

used for cell motility

what is the extracellular matrix

function to provide mechanical support and helps bind adjacent cells

what is the most abundant in the extracellular matrix

collagenw

what is found in plants and not in animal cells

cell wall and plastids

what are cell walls

provide support in plants

what are plastids

variety of organelles serving various metabolic activities such as chloroplasts for photosynthesis

what are some traits of prokaryotes

no nucleus

single, circular, naked, double stranded DNA

ribosomes are (50S+30S=70S)

cells walls are made of peptidoglycan (bacteria) polysaccharides (archaea) with sticky capsules on the cell wall

flagella are constructed from flagellin not microtubules

what is phospholipid membrane permeability

allows small, uncharged, hydrophobic molecules to freely pass through the membrane

other molecules that are large, polar, or uncharged requires a transporter

what is the function of cholesterol in cell membrane properties

regulates fluidity of cell membrane

what are channel proteins

passage through the membrane for hydrophilic (water-soluble), polar, and charged substances

what are types of channel proteins

ion channels and porins

what are types of ion channels

voltage- : responds to differences in the charge across the membrane

mechanically- : open and close in response to pressure, vibration, or temperature

ligand-: signaling a molecule binds an opens the channel

what are porins

less specific; pass ions and polar molecules

what are carrier proteins

changes shape after binding to specific molecule that enables it to be pass across

what are transport proteins

proteins that can use ATP to transport materials across the membrane; includes active transport (sodium-potassium pump) and facilitated diffusion

what is passive transport

goes down the gradient

no ATP is required

what are examples of passive transport

simple diffusion, osmosis, dialysis, plasmolysis, facilitated diffusion, and countercurrent exchange

what is active transport

against gradient

uses ATP

moves solutes like small ions, amino acids, and monosaccharides

what is phagocytosis

plasma membrane invaginates around undissolved material (solid), like bacteria

what is pintocytosis

plasma membrane invaginates around dissolved material (liquid)

what is receptor- mediated endocytosis

form of pintocytosis in which specific molecules called ligands bind to receptors wh

what happens when a cell is placed in a hypertonic solution

there is more solute concentration compared to the cell so water will flow from the cell to the outside solution and shrivel

what happens if a cell is placed in a hypotonic solution

there is more solute in the inside of the cell compared to the outside so water will rush into the cell and it will lyse

what happens if a cell is placed in an isotonic solution

water is moving at equal rates in and out of the cell

what are anchoring junctions

includes desmosomes; connects 2 cells together

what are tight junctions

encircles each cell, producing a seal that prevents the passage of materials between cells; is characteristic of cells lining the digestive tract and blood brain barrier

what are gap junctions

narrow tunnels between animal cells; allow passage of ions and small molecules