Bio Unit 2 chap 6

cell fractionation

the disruption of a cell and separation of its parts by centrifugation at successively higher speeds (lower speeds=larger components, higher speeds=smaller)

eukaryote

has membrane bound organelles, DNA is in the nucleus, consists of plants, animals, fungi, and protists

prokaryote

does NOT have membrane bound organelles, DNA resides in a space called the nucleoid, consists of bacteria and archaea

cell/plasma membrane

a selective barrier around ALL CELLS that is SEMIPERMEABLE and regulates its chemical composition, made up of a phospholipid bilayer that has hydrophilic heads facing outwards and hydrophobic tails facing inward

cytosol

the semifluid, gel-like substance inside cells where organelles are suspended

nucleoid

the area in prokaryotic cells where the DNA is generally located

cytoplasm

the contents of the cell bound by the cell/plasma membrane, in eukaryotes: the portion exclusive of the nucleus

organelles

different environments in the cell that each carry out specific metabolic functions MEMBRANE BOUND

nucleus

organelle that contains genetic material (DNA) in the form of chromosomes, made out of chromatin

nuclear envelope

the double membrane that surrounds the nucleus, dotted with pores that regulate traffic with the cytoplasm, the outer membrane is continuous with the endoplasmic reticulum (ER)

nuclear lamina

a net like array of protein filaments that lines the nuclear envelope and helps maintain its shape

chromosomes

structures that carry genetic information

chromatin

the complex of DNA and proteins that make up chromosomes

46

how many chromosomes does a human have in the nucleus

nucleolus

the site of rRNA synthesis (ribosomal RNA), also synthesizes ribosome parts, may play a role in cell division and the life of a cell

ribosomes

cellular components that carry out protein synthesis

free ribosomes

ribosomes suspended in cytosol- mainly produce proteins that function WITHIN THE CELL/CYTOSOL

bound ribosomes

ribosomes on the rough ER/nuclear envelope- mainly make proteins inserted into other membranes, or for secretion from the cell (export)

endomembrane system

system that contains both ERs, golgi, lysosomes, vesicles/vacuoles, and the plasma membrane

vesicle

sacs made out of membrane inside or outside the cell, can be used to transport proteins/other stuff

Smooth ER

organelle that synthesizes lipids (oils, steroids, new membrane phospholipids), metabolizes carbohydrates, detoxification of drugs and poisons, and stores calcium ions

Rough ER

makes secretory proteins from its bound ribosomes, also a membrane factory- produce membrane phospholipids

glycoproteins

a protein with one or more covalently attached carbohydrates

golgi apparatus (golgi body)

a stack of flat, membranous sacs that modifies, stores, and routes proteins (products of the ER), and synthesizes some other products like noncellular carbs

cis face

receiving side of the golgi apparatus

trans face

shipping side of the golgi apparatus

lysosome

a sac of hydrolytic enzymes that digests macromolecules; can be used to break down old cell material or even fight viruses and bacteria

phagocytosis

process of large particles or small organisms being taken up by a cell and then digested

vacuoles

stores extra molecules cell might need- water, lipids, carbs, etc. the large central one of these contains inorganic ions such as potassium and chloride

mitochondria

serves as the site of cellular respiration; uses oxygen to break down organic molecules then synthesize ATP (FOUND IN BOTH ANIMAL AND PLANT)

chloroplasts

sites of photosynthesis in plants cells, absorbs sunlight and uses carbon dioxide and water to make sugars for energy

endosymbiont theory

theory that mitochondria and chloroplasts were actually engulfed by the cell as prokaryotes and then evolved to be with its host cell

cristae

folds of the inner mitochondria membrane, increases the surface area in order to increase efficiency/reaction number and rate of the organelle

mitochondrial matrix

inclosed by the inner membrane of the mitochondria, where cellular respiration occurs

thylakoid

flattened sac in a chloroplast that carries out photosynthesis (light→chemical energy)

grana

stacks of thylakoids

stroma

fluid outside the thylakoids

intermembrane space

space between the inner and outer membranes of a chloroplast

plastids

amyloplast, chloroplast, chromoplast, found in photosynthetic eukaryotes

peroxisomes

removes hydrogen atoms from various substances and transfers them to oxygen, producing hydrogen peroxide, can be used to break down fatty acids for cellular respiration, or to detoxify alcohol. After converting to hydrogen peroxide, they also have an enzyme to convert that to water

cytoskeleton

a network of fibers extending throughout the cell that gives it its structure- consists of microtubules, microfilaments, and intermediate filaments

microtubules

thickest of three structural elements, they shape and support the cell as well as serve as tracks for which organelles equipped with motor proteins can move, also make up the centrosome/centrioles

centrosome

functions as a microtubule organizing center and is important in cell division, contains two centrioles that are also important in cell division

flagella

a long tail some cells use for motility, made of microtubules

cilia

moves fluid past the cell, kind of like little hairs, made of microtubules

microfilaments

thin solid rods that pull and bear tension to keep structure in place, also play a role in cell motility

intermediate filaments

reinforces the shape of the cell and fixing the position of certain organelles

cell wall

a protective layer external to the cell wall in plants, prokaryotes, fungi and some protists; made of cellulose and peptidoglycan

middle lamella

layer of adhesive extracellular material, found between primary walls of adjacent young cells

extracellular matrix (ECM)

meshwork surrounding animal cells, consisting of glycoproteins, polysaccharides, and proteoglycans, secreted by cells

plasmodesmata

an open channel through cell walls of adjacent plant cells, connecting the cytoplasm and allowing stuff to flow through

desmosomes

function like rivets, creating sturdy sheets of cells