ap bio unit 2

cell functions

cell theory

all living things are composed of one or more cells

a cell is the basic unit of life

all cells come from an ancestral cell 

prokaryotic cells

lack internal membranes, a nucleus, and membrane bound organelles

DNA is in an unbound Nucleoid region, cytoplasm is bound by plasma membrane 

archea and bacteria

prokaryotic domains of life 

eukaryotic cells

has internal membranes,membrane bound organelles, nucleus 

has DNA in a nucleus that is bounded by a nuclear envelope

larger than prokaryotic cells 

eukarya 

eukaryotic 

fungi,plants 

plasma membrane

provides a lipid boundary for the cell’s contents, separating the cell from its environment 

selective barrier that allows passage of oxygen, nutrients, and waste to surface

cytosol

semifluid gel that fills the cell and is the site of many metabolic chemical reactions

chromosomes

lengths of DNA that contains genes (codes for proteins)

ribosomes

small parts responsible for protein synthesis based on mRNA

composed of rRNA and proteins all cells have ribosomes

found in animals, plants, and bacteria

cell membrane

allows cells to maintain internal environments different from external environments

found in plants, animals, bacteria

whyis the inside of bilayer nonpolar

allows small nonpolar molecules to pass through the cell

which cells have a greater SA:V ratio

small cells

rough ER

has ribosomes on its surface and helps compartmentalize the cell

synthesizes proteins

found in plants and animals

smooth ER

cellular detoxification and lipid synthesis

golgi complex

series of membrane sacs, modifies newly-made proteins and packages them for distribution 

found in animals and plants

mitochondria

has double membrane, outer is smooth, inner is highly folded

converts food into energy 

found in animal and plant cells 

lysosomes

membrane sacs containing hydrolytic enzymes for intracellular digestion

digest materials inside of vacuoles

recycles materials and old organelles 

initiates apoptosis

found in eukaryotic cells

vacuoles

membrane-bound sacs used for mostly storage

found in animals, plants, and bacteria

chloroplasts

found in algae and plants, preform photosynthesis 

contains thylakoids

mitochondria double membrane

allows for improved efficiency in cellular respiration

move metabolic reactions into compartments

cellular respiration

transfers chemical energy of organic compounds into useable energy for the cell- ATP

inner mitochondria membrane function

cellular respiration

outer mitochondria membrane

provides space for membrane bound organelles

thylakoids

stacks of sacs within the chloroplasts

the site for light-dependant photosynthesis reactions 

grana

stacks of thylakoids

stroma

the fluid that fills chloroplasts

cristae

a fold on the inner membrane of the mitochondria

provides surface area for chemical reactions to occur 

matrix

fluid in the inner membrane of the mitochondria

holds enzymes, DNA, ribosomes

intermembrane space

space between the inner and outer membrane space

apoptosis

programmed cellular death

endomembrane system

network of membranes inside eukaryotic cells that work together to modify, package and transport lipids and proteins 

endomembrane system organelles

nuclear envelope, rough & smooth ER, golgi, vesicles, lysosomes, plasma membrane 

what is a cell membrane

fluid mosaics of lipids and proteins

peripheral proteins

proteins on the cell membrane’s exterior and interior surface

hydrophilic, polar 

integral proteins

penetrate the cell membrane, help transport

have a hydrophobic side, and a hydrophillic side 

transmembrane proteins 

pass completely through the phospholipid bilayer 

steroids 

help membrane fluidity

more steroids=more fluidity 

glycoproteins

help cellular identification

one or more carbs attatched to the membrane

cytoskeleton

structural framework made of proteins that helps the cell keep its shape, hold organelles in place, network for trafficking

selective permeability

cell membrane’s ability to regulate the molecules that are able to pass in and out of the intracellular environment

molecules that can easy pass through the membrane 

small and nonpolar molecules

molecules that are unlikely to pass through the membrane 

polar/charged molecules

transport protein 

help large proteins cross the membrane 

osmotic lysis

when a cell absorbs water and breaks open

bacterial walls

made of peptidoglycan

provide shape and protection

archea walls

mode of polysaccharides or proteins and adapted for extreme environments

fungi walls

mode of chitin, provides rigidity and resistance to osmotic pressure

plants

made of cellulose, structural support and control of water movement

passive transport

process by which molecules diffuse across a membrane from high to low concentration 

no energy input is required 

gradient

difference in concentrations between 2 different areas 

larger difference=faster diffusion

active transport

moves molecules against the concentration gradient

requires energy input from the environment  and a transport protein

bulk transport

cells are capable of moving large quantities of substances into and out of the cytoplasm 

uses energy

endocytosis

the process by which a cell can engulf material

taking something into the cell 

phagocytosis 

endocytosis of solids 

pinocytosis

endocytosis of liquids

exocytosis

endocytosis in reverse, removes large cellular waste or releases cellular products 

facilitated diffusion

diffusion of large/polar/charged molecules

uses transport proteins 

allows hydrophilic molecules to pass 

aquaporins

transport proteins move water

ion channels

transport proteins that move ions

how does a membrane become polarized

movement of ions creates electrochemical gradient across a cell membrane

osmosis

diffusion of water through a selectively permeable membrane

passive transport of water from areas of high to low water concentration 

water potential

measurement that combines the effects of solute concentration and pressure 

the ___ solute in a solution, the greater the interactions between solutes and polar water molecules

more

water flows from ___ to___ water potential 

high to low 

tonicity

the ability of a surrounding solution to cause a cell to gain or lose water

isotonic solution

solute concentration is the same as the inside of the cell

hypertonic solution

solute concentration greater than inside cell

cell loses water

hypotonic solution

solute concentration is less than inside the cell

cell gains water

osmoregulation

the ability of organisms to maintain water balance with their environment and control their internal solute concentration 

contractile vacuole

an adaptation possessed by freshwater protists, paramecia, to osmoregulate and maintain homeostasis 

nucleus

holds DNA

found in plant and animal cells

nucleolus

produces ribosomes

found in plant and animal cells

flegella

helps bacteria swim found in bacteria cells

cilia 

moves the cell around 

found in plants and animal cells 

amyloplast

synthesizes starch

found in plants

peroxisome

detoxifies cells and breaks down lipids

found in animal cells

cytoplasm

holds organelles

found in all cells

cytosol

provides environment for processes

found in all cells

cell wall

provides structure to the cell. Prevents things from entering 

found in plant cells

centrioles

forms centrosomes to organize spindles for cell division 

found in plant and animal cells

smooth er

synthesizes lipids and detoxifies the cell

found in plants and animals

ETC proteins

creates an electrochemical gradient that leads to the creation of ATP

mitochondrial inner membrane 

highly convoluted,increased surface area of cristae allow increased ETC proteins and ATP synthases maximizing oxidative phosphorylation 

where do prokaryotic cells isolate functions 

different cellular areas 

how is voltage created

differences in the distribution of positive and negative ions across a membrane

membrane potential

voltage difference across a membrane

sodium-potassium pump

active transport protein

maintains ion gradient in animal cells

transport proteins

require energy to move molecules against the concentration gradient and maintain concentration gradients, preventing the cell from reaching equilibrium

oxidative phosphorylation 

the cellular process that generates the majority of the cell's energy in the form of ATP by using the energy from the oxidation of food molecules

grana

in chloroplasts, increase Surface Area for photosystems and ETC proteins in the THylakoid membranes, increasing photophosphorylation and NADPH in the light reactions 

NADPH

essential for synthetic or anabolic reactions, including the synthesis of fatty acids, steroids, and nucleotides. 

endosymbiont theory

mitochondria and chloroplasts contain shared characters with prokaryotes, providing evidence of common ancestor y 

shared characters

features possessed by the descendants of a common ancestor and define a clade

clade 

a group of different organisms that share a common ancestor 

symbiosis

a close, long-term, physical interaction between 2 different organisms

endosymbiont theory story

an ancestral eukaryotic cell engulfed an ancestral mitochondrion, establishing a mutualistic relationship. The eukaryote survived and reproduced often, establishing a lineage of eukaryotes that too possessed mitochondrion.

mutualism

a type of symbiosis where both parties benefit

endosymbiont theory on how plant cells are made

a eukaryote engulfed a photosynthetic prokaryote and survived and reproduced often

all living cells contain…

a genome and ribosomes 

when is pressure potential zero

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