AP Bio Unit 2

what are microtubules made of?

tubulin

what are microtubules involved in?

cell shape, chromosome + organelle movement, cilia and flagella

which cytoskeleton element is the thinnest?

microfilament

what are microfilaments made of?

actin

what are microfilaments involved in?

cell shape/movement, muscle contraction, cytoplasmic streaming, cell division

what are intermediate filaments made of?

various proteins, including keratin

what are intermediate filaments used for?

maintaining cell shape and anchoring organelles and the nucleus

what is the centrosome

a region near the nucleus that organizes microtubules in animal cells

what is the structure of a centriole

9 sets of triplet microtubules

what are plant cell walls primarily made of?

cellulose fibers

what are the functions of a plant cell wall?

protection, support, structure, prevent excess water uptake

what does sodium-potassium pump do?

use energy to transport sodium and potassium across the membrane

what is an electrochemical gradient?

a combo of a concentration gradient and electrical gradient

what is cotransport?

using the movement of 1 substance down its gradient to drive the movement of another substance

what’s hypotonic solution?

solution w/ low solute concentration outside the cell

what happens to animal cell in hypotonic solution

water enters and cell may swell and lyse

what happens to plant cell in hypotonic solution

becomes turgid

what’s an isotonic solution?

solution w/ same solute concentration as the cell

what happens to animal cell in isotonic solution

no net movement of water

what happens to plant cell in isotonic solution

becomes flaccid

what’s hypertonic solution?

solution w/ higher solute concentration outside the cell

what happens to animal cell in hypertonic solution?

water leaves cell, causes it to shrivel

what happens to plant cell in hypertonic solution?

cell undergoes plasmolysis

what happens to membrane fluidity when temp decreases

membrane tends to become less fluid

what are integral membrane proteins?

proteins embedded in membrane

what are transmembrane proteins

integral proteins that span the entire membrane

what are peripheral proteins

proteins attached to the surface of the membrane

what’s selective permeability?

membrane allows some substances to pass through more easily than others

what’s diffusion

movement of substance from high to low concentration

does simple diffusion require atp

no

what’s osmosis

diffusion of water across a selectively permeable membrane

in osmosis, water moves toward side with what?

higher solute concentration

what’s facilitated diffusion?

movement down a concentration gradient through a membrane protein

does facilitated diffusion require atp?

no

what’s active transport?

movement of substances against a concentration gradient using energy

what’s extracellular matrix (ECM)?

network of proteins and other molecules outside animal cells that help support and organize cells

what protein is a major component of the animal ECM

collagen

what are integrins

proteins that connect the ECM to the cell

what are plasmodesmata

channels connecting neighboring plant cells

what do tight junctions do

prevent leakage between adjacent animal cells

what do desmosomes do

anchor cells together and provide strength

what do gap junctions do

allow ions and small molecules to pass between animal cells

what structures make up the endomembrane system

nuclear envelope, ER, golgi app, lysosome, vacuoles, plasma membrane

function of rough ER?

produces and processes proteins, especially proteins destined for secretion or membranes

why is rough ER called “rough”?

cause ribosomes are attached to its surface

what does smooth ER do?

lipid synthesis, carbohydrate metabolism, calcium storage, and detoxification

function of golgi apparatus?

modifies, sorts, packages proteins and other molecules d

what are ribosomes responsible for?

protein synthesis

what’s the function of a mitochondria?

involved in cellular respiration and ATP production

what are cristae?

folds of the inner mitochondrial membrane

what’s the mitochondrial matrix?

fluid-filled compartment enclosed by the inner mitochondrial membrane

what’s the function of chloroplasts

photosynthesis

what’s the pigment found in chloroplasts

chlorophyll

what are thylakoids?

membrane-bound sacs inside chloroplasts

what are grana?

stakcs of thylakoids

what’s the stroma?

fluid surrounding thylakoids in a chloroplast

what are peroxisomes

membrane-bound compartments involved in metabolic reactions and production/conversion of hydrogen peroxide

what are 3 types of cytoskeletal fibers?

microtubules, microfilaments, intermediate filaments

which cytoskeletal element is the thickest?

microtubules

what are the cis and trans faces of the golgi

cis face receives materials, trans face ships them out

what’s the function of lysosomes

digestion and recycling using hydrolytic enzymes

what are vacuoles used for?

storage, digestion, water balance

what’s the basic structure of a cell membrane

phospholipid bilayer

what does a “fluid mosaic” mean

membrane is fluid, w/ proteins and other components embedded w/ it

which part of a phospholipid is hydrophilic?

phosphate head

which part is hydrophobic?

fatty acid tails

where are membrane carbohydrates located/

on extracellular side of membrane

what are glycoproteins

proteins w/ carb attached

what are glycolipids

lipids w/ carb attached

what’s the function of membrane carbohydrates

cell-cell recognition

what does cholesterol do in the membrane?

helps regulate membrane fluidity

what are the 4 structures found in all cells

plasma membrane, cytosol, chromosomes, ribosomes

what’s the main difference between prokaryotic and eukaryotic cells?

prokaryotic cells lack a nucleus + membrane-bound organelles

where’s DNA located in prokaryotic cell

in nucleoid region

what does SEM stand for

scanning electron microscope

what does SEM primarily show

surface of a speciman w/ 3D appearance

what does TEM stand for?

transmission electon microscope

what does TEM primarily show?

internal structures of a speciman

what is cell fractionation

breaking cells apart and separating their components using centrifugation

why do cells generally remain small

smaller cells have a higher SA:V ratio, making exchange w/ the environment more efficient

what’s the function of the nucleus

houses DNA and controls gene expression

what’s the nucleolus

region where ribosomal components are produced

what’s chromatin

DNA and associated proteins inside the nucleus