AP Bio Unit 2 Vocab Ch. 6

light microscopes

Adv: can observe both living and non-living things

Dis: max magnification is 1000x

scanning electron microscope (SEM)

studies surface

Adv: great depth of field

Dis: can't observe living things

transmission electron microscopes (TEM)

looks at inside of cells

Adv: can produce an image of very small structures

Dis: can’t observe living things

cell fractionation

separates different parts of the cell with a centrifuge

cell size

smaller objects have higher ratio of surface area to volume

eukaryotes can be larger because they are compartmentalized and have more cells

what is the cell limited by?

large cell size doesn’t diffuse materials efficiently

small cells don’t have enough room

structures in all cells

plasma membrane

cytoplasm (prokaryotes in whole thing, eukaryotes betw nucleus and membrane)

ribosomes

genetic info (prokaryotes in nucleoid, eukaryotes in nucleus)

prokaryotic cells

unicellular

simple and small

no membrane-bound organelles

circular nucleoid (no nucleus)

bacteria/archaea

endosymbiotic theory

organelles in eukaryotes originated as a symbiotic relationship betw separate singe-celled organisms

evidence for endosymbiotic theory

mitochondria and chloroplasts are:

-double-membrane bound

-have DNA

-similar ribosomes to prokaryotes

-self-replicate

-same size

-use many prokaryotic-like enzymes

eukaryotic cells

can be multicellular

larger/complex

membrane-bound organelles that are compartmentalized

have nucleus

plasma membrane

what enters and exits the cells

phospholipid bilayer, variety of protein carbohydrates

nucleus

control center

nucleolus

makes rRNA/ribosomes

nuclear envelope

double membrane, pores for RNA to exit

chromatin (DNA)

uncoiled chromosomes in linear form

nuclear lamina

network of protein filaments inside the nucleus for structure

ribosome

protein synthesis

free ribosome: not attached to ER, makes proteins for cytosol

bound ribosome: attached to ER or nuclear envelope for protein to leave cell or go in membrane

ribosome extras

made of small and large subunits

3 binding sites

can switch between free and bound

endoplasmic reticulum

connected to nuclear envelope

aids in moving stuff around the cell

smooth ER

no ribosomes

makes lipids, detoxifies drugs, breaks down carbs, stores calcium

rough ER

studded w/ ribosomes

makes secretory and membrane proteins

ER extras

inside is lumen - protein folding

secretory proteins produced are glycoproteins and packaged in vesicles

golgi apparatus

packaging, modifying, secreting substances that came from ER or makes its own

cis(receiving) and trans(shipping)

lysosome

digestive, break down

only in animal cells

vesicle formed in golgi that contains hydrolytic enzymes

phagocytosis

digesting things taken into the cell

autophagy

digesting and recycling old parts of the cell

tay-sachs disease

lysosomal storage disorder

vacuoles in animals

smaller, for storage

food vacuole: combine with lysosomes to digest

contractile vacuole: help get rid of excess water

vacuole in plants

large central vacuole

increases and decreases turgor pressure

tonoplast

membrane around vacuole in plant cells

mitochondria

site of cellular respiration

converts glucose to ATP

double membrane-bound

cristae: folds that increase surface area

chloroplasts

plastid

site of photosynthesis

use sun to convert H2O and CO2 into glucose

double-membrane bound

filled w/ stroma and stacks of thylakoids (grana)

peroxisomes

detoxify alcohol and drugs

makes hydrogen peroxide as a byproduct

cytoskeleton

structural support

helps anchor organelles

aids in cell movement

microtubules

thickest

hollow rods made of tubulin protein

helps chromosomes move during cell division

forms cilia and flagella

centrosomes

located near nucleus

microtubules made here

centrioles

found in centrosomes in animal cells

cilia and flagella

made of microtubules that make cell move

basal body: anchors them

dynein arms

motor molecules that bend the cilia and flagella

microfilaments

thinnest

made of actin protein

maintains shape

work with myosin protein in muscle movement

intermediate filaments

midsized

maintains shape

make of keratin protein

cell wall

protect, maintain shape, prevent excess water uptake

made of cellulose

primary cell wall

starts as thin and flexible and then hardens once mature

secondary cell wall

under the primary cell, strong like wood

middle lamella

glues plant cells together

plasmodesmata

channels in the cell walls of plants to pass materials betw cells

like gap junctions

extracellular matrix

provides support, adhesion, movement, regulation

structure in animal cells

made of glycoproteins (collagen)

desmosome

holds animal cells together/reduces friction

tight junction

prevents leakage

gap junction

lets substances pass through, cell signaling