Unit 2: Cells

Ribosomes: job

Produce proteins

Rough ER: job

Produce proteins

Processes and modifies proteins

Smooth ER

Produces lipids

Detoxifies drugs

Produces secretory vesicles

Golgi body

Synthesis and packaging of materials (often proteins)

Produces secretory vesicles

Produces lysosomes

Vesicles

Transport

Mitochondria

Produce ATP by cellular respiration

Lysosomes

Digest stuff

Vacuoles

Animal - storage

Plant - water reservoir/storage

Chloroplast

Produce glucose (from sunlight) by photosynthesis

Nucleus

Controls the cell by using DNA to make proteins

Makes mRNA during transcription using protein synthesis

Cytoskeleton

Gives the cell physical structure

Vesicle movement

Anchors cell organelles and the cell in place

Peroxisomes

Takes care of byproduct

Breaks down fatty acids so they can be used by mitochondria to produce ATP through cellular respiration

Detoxifies alcohol

Glycolipids

Carbohydrate head with two fatty acid tails

Stabilizes membrane

Glycoprotein

Carbohydrate head with a protein

Used in cell recognition

Membrane proteins

On either surface or run right through the membrane

Used for a variety of functions

Transport proteins

Channel or carrier proteins

Transport specific molecules through membrane

Phospholipid

Polar heads face outwards, non-polar tails face inwards

Cholesterol

Animal membranes only

Stabilize phospholipid tails

Cytoskeleton filaments

Long protein chains run throughout the cell

Helps cell hold its shape

Movement of vesicles and vacuoles

High to low concentration

Passive method of transport

Low to high concentration

Active method of transport

Diffusion: mechanism

Wiggle between the phospholipids

Osmosis: mechanism

Channel protein, water pore/polar tunnel

Facilitated diffusion/transport: mechanism

Carrier protein - two halves rock open and close

Active transport: mechanism

Carrier protein

Endocytosis/exocytosis: mechanism

Vesicle

Solvent

Water - what stuff dissolves in

Solute

What we mix into the water

Molarity

Higher the molarity, higher concentration it is

Concentrated

More water inside the cell

Diluted

More water outside the cell

Bulk flow

Large amounts of molecules moving

Equilibrium may not be exact

Confirmational change

Physical change in the receptor site

Co-transport

1 carrier protein can move 2 different molecules at the same time

Aquaporin

Water molecules move at a rate of 3 billion per second

Osmotic pressure

Force having to do with how steep the concentration gradient is

Pressure created by water moving to the side with greater solute concentration

Tonicity

Strength of a solution (solute or solvent)

Concept revolves around osmosis

Isotonic

Solute concentration in solution is equal to solute concentration in the cell

Hypotonic

Solute concentration in solution is less than solute concentration in the cell

Hypertonic

Solute concentration in solution is more than solute concentration in the cell

Water moves into the cell

Hypotonic in relation to water

Water moves out of the cell

Hypertonic in relation to water

Active method of transport

Has to provide ATP molecule

Moving from low to high concentration

Diffusion: molecules

Small, non-polar molecules & gases

Osmosis: molecules

Water

Facilitated diffusion/transport: molecules

Small, polar molecules & ions

Active transport: molecules

Small, polar molecules & ions

Endocytosis: molecules

Macromolecules and cells

Exocytosis: molecules

Largish sizes (macromolecules)

Pinocytosis

Cell-drinking

Macromolecules (sometimes several at a time)

Phagocytosis

Cell-eating

Whole cells (usually just one at a time)

Receptor mediated Endocytosis

Receptor proteins/ligands on surface of cell membrane allow specific molecules to attach and active Endocytosis

DNA in prokaryotes

Circular, in plasmids

DNA in eukaryotes

Linear, packaged in membrane, wraps around histones

Prokaryotes domains

Archaea and bacteria

Eukaryotes domain

Eukaryotes

Cell size: cell membrane

Surface area

Cell size: inside the cell

Volume

Special cells

Have more membrane

Endosymbiont:

Cell living within another cell

Endosymbiont theory

Eukaryotic cells evolved from prokaryotic cells

Functions of the cell wall

Protects the plant cell

Maintains its shape

Prevents excessive uptake of water

Mitochondria and chloroplasts

Have 2 membranes

Contain ribosomes and circular DNA molecules attached to inner membranes

Autonomous organelles that grow and reproduce within the cell

Composition of the cell wall

Cellulose embedded with other polysaccharides and proteins

Primary cell wall

Thin and flexible wall secreted first by a plant cell

Middle lamella

Thin layer rich in pectins that glues primary walls of adjacent cells together

Secondary cell wall

Strong and durable matrix

Offers the cell protection and support

Extracellular matrix (ECM)

In animal cells instead of plant cells

Collagen, fibronectin, proteoglycan complex, integrins

Collagen

Fibers are embedded in web of proteoglycan complexes

Fibronectin

Attaches the ECM to integrins embedded in cell membrane

Proteoglycan complex

Hundreds of proteoglycan molecules attached noncovalently to a single long polysaccharide molecule

Integrins

Transmits signals between the cell’s external environment and interior

Plasmodesmata

Intercellular junctions between plant cells

Cytosol passes between the cells

Chemical molecules in cytosol used to communicate between cells

Intercellular junctions between animal cells

Tight junction, desmosome, gap junction

Tight junction

Prevents leakage of extracellular fluid across a layer of epithelial cells

Desmosome

Attaches muscle cells to each other in a muscle

Fastens cells together into strong sheets

Gap junction

plant plasmodesmata

connects cytoplasm to neighbouring cytosol

Fibers that make up the cytoskeleton

Microtubules

Microfilaments

Intermediate filaments

Flow rate

Speed and amount of water molecules moving

0 degrees K

-273 degrees C

1 chromosome

Prokaryotes

Multiple chromosomes

Eukaryotes

Prokaryotes and eukaryotes similarities

Cytosol, cell membrane, ribosomes, nucleic acid material

Compartmentalization increases ___

Surface area

More membranes =

More chemical reactions

Compartmentalization: toxic chemicals can be isolated ____

Inside a vacuole

Compartmentalization: allows cell to be…

More complex and specialized

Free ribosomes

Produce ribosomes that stay in the cell

Attached ribosomes

Produce proteins that will leave the cells/for export

Packaging of material

Puts chemical address on the molecule

Center of mitochondria

Matrix (where DNA and ribosomes are)

Folds in mitochondria

Cristae

Thyloroids in chloroplast

Where photosynthesis happens

Healthy cell

Large surface area to volume ratio

Pectins

Sticky polysaccharides

Lysed

Animal cell in hypotonic solution

Shriveled

Animal cell in hypertonic solution

Turgid (normal

Plant cell in hypotonic solution

Flaccid

Plant cell in isotonic solution

Plasmolyzed

Plant cell in hypertonic solution