Unit 2 Cellular Structure and Function ~ AP Biology

compartmentalization

organelles that are surrounded by a membrane in order to increase efficiency of cellular processes

plasma membrane

allows passage of nutrients and wastes to service the sell

cytosol

dense water based gel that cushions organelles

cytoplasm

cytosol and the organelles

nucleoid

in prokaryotes and contains DNA

nucleus

membrane bound organelle that contains and protects DNA and the nucleolus

nucleolus

dense region of RNA in the nucleus that makes ribosomal subunits

ribosome

made of protein and rRNA that is not membrane bound and forms polypeptide chains

smooth endoplasmic reticulum

made of membrane and synthesizes lipids and detoxifies drugs and waste

rough endoplasmic reticulum

highly folded membranes that fold proteins

transport vesicle

made of phospholipid bilayer with hydrophilic interior and move biomolecules form organelle to organelle

secretory vesicle

transports biomolecules to cell membrane to release proteins for secretion via exocytosis

golgi apparatus

flattened membrane that modifies biomolecules from the ER, makes lysosomes, and packages and sorts biomolecules into vesicles

lysosome

membrane bound organelle with digestive enzymes and a low pH that digests worn out parts of the cell and food, and assists with apoptosis

food vacuole

stores and digests food the cell engulfs

contractile vacuole

maintain water balance by collecting excess water and spitting out in paramecia

central vacuole

membrane bound organelle that stores things in plants and maintains turgor pressure

mitochondia

double membrane organelle that does cell respiration

cristae

inner folds in a mitochondria

matrix

internal space in a mitochondria

chloroplast

double membrane organelle that does photosynthesis

thylakoid

disk

granum

stack of thylakoids

stroma

fluid in chloroplasts

cytoskeleton

strands/fibers made of protein that assist in strength, structure, and mobility

actin filaments

cell movement, muscle contraction, smallest

intermediate filaments

support organelles

microtubules

vesicle transport, cell motility, many, biggest

centriole

bundle of microtubules that helps organize microtubules and is active during mitosis/meiosis

centrosome

two centrioles, functional during mitosis, organizes microtubules, moves chromosomes

cilia

short, hairlike projections on surface of cell in eukaryotes, helps with movement of cell

flagella

long, whiplike projections in pro/eukaryotes to move the cell

cell wall

in plants, made of cellulose

in fungi, made of chitin

in prokaryotes, made of peptidoglycan

helps with structural support and protection

peroxisomes

membrane bound organelle that metabolizes lipids and break down H₂O₂

endosymbiotic theory

describes a possible origin of eukaryotes

evidence of endosymbiotic theory

1. both have double membranes

2. both have own DNA

3. both replicate independently similarly to binary fission

4. both have a similar size to bacteria

endomembrane system

group of organelles that work together to synthesize, modify, and package proteins and lipids

fluid mosaic model

the dynamic pattern of the cell’s membrane

increase fluidity

unsaturated fatty acids

decrease fluidity

saturated fatty acids (viscous)

cholesterol

small 4 ringed lipid that mediates fluidity

glycolipids

have short carb chains attached

glycoproteins

have short carb chains attached

integral proteins

have hydrophobic R-groups embedded in phospholipid tales

peripheral proteins

have hydrophilic r-groups that interact with heads/other polar stuff

passive transport

molecules move along conc. gradient w/o energy

simple diffusion

molecules move directly through the bilayer until dynamic equilibrium (small nonpolar, small uncharged)

facilitated diffusion

molecules move through the proteins until dynamic equilibrium through channel/carrier proteins (large hydrophilic or charged molecules)

channel proteins

continuous flow, H₂O and ions (aquaporins)

carrier proteins

conformational change, small polar molecules

active transport

molecules move against their conc. gradient using ATP hydrolysis

sodium potassium pump

3 NA+ enter the pump and ATP binds from inside of cell —> ATP is hydrolyzed and leads to conformational change —> 3NA+ leave and 2K+ enter, phosphate leave and 2 K+ enter the cell

membrane potential

membrane is polarized when different charges are maintained across the bilayer (difference in voltage across the bilayer) (allows for electrical transmission of signals (nervous system))

endocytosis

bring in material

phagocytosis

bring in solid particles (food vacuole)

pinocytosis

bring in liquid particles (transport vesicle)

receptor mediated

bring in particles attached to receptors on cell membrane (transport vesicle)

exocytosis

vesicle containing cell products/waste fuses with membrane to secrete contents

osmosis

the diffusion of water across a membrane through aquaporins (channel proteins)

aquaporins

channel proteins used for osmosis

hypertonic

solutions with more solutes

hypotonic

solutions with less solutes

isotonic

solutions with equal amounts of water/solutes

cytolysis

burst, animal cells

crenate

shrivel, animal cells

plasmolysis

membrane pulls away from cell wall

turgid

hard cell pushing on cell wall

flaccid

plants in isotonic solution

Endosymbiont

An organism that lives inside another in a mutualistic relationship

Cell theory

All living things are made of cells, cells are the basic unit of life, and all cells come from existing cells

Prokaryote

A unicellular organism without a nucleus or membrane-bound organelles

Eukaryote

A cell with a nucleus and membrane-bound organelles

Surface-area-to-volume ratio

the amount of surface area per unit of volume; affects cell efficiency

Sphere

A round 3D shape where all points on the surface are equidistant from the center.

cube

A 3D shape with six equal square faces

Rectangular Solid

A box-shaped 3D figure with rectangular faces

Cylinder

A 3D shape with two parallel circular bases connected by a curved surface

Metabolic rate

The speed at which the body uses energy

Microvilli

Tiny projections that increase surface area for absorption

Amphipathic

A molecule with both hydrophobic and hydrophilic parts