by the end of today: name a function of each organelle

By the end of today: Name a function of each organelle

The nucleusContains genetic

informationHas a double

membrane with pore complexes

Contains nucleolus – a structure where rRNA is synthesized

Fun fact: your red blood cells do not have nucleii (anucleated)

Endoplasmic reticulumSmooth ER

Synthesis of lipids, metabolism of carbohydrates and detoxification of drugs and poisons

Fun fact – cells that synthesize hormones (steroids which are lipids) , such as testes and ovaries are rich in smooth ER

Another fun fact - Also proliferation of smooth ER in response to drugs and alcohol

Rough ERProteins are

synthesized using ribosomes and then in the rough ER they are folded and carbohydrates are added to make a glycoprotein

The membrane buds off to form a transport vesicle which takes the protein to another area in the cell

GolgiProducts of the ER are

modified, stored and sent to other destinations in the golgi

Golgi can also manufacture macromolecules, such as polysaccharides

StrucutreTrans face – shipping sideCis face – near the rough

ERFun fact – molecular

identification tags are added to golgi products that aid in their placement within the cell

Lysosomes – Digests macromolecules using enzymesPhagocytosis – Eating or digestion of products

Autophagy – Breaks down damaged organelles

Lysosomal lipase is missing

Vacuoles Different functions in

different cellsEx. Food vacuoles,

contractile vacuoles (pump excess water out of the cell), and in plant cells central vacuole

Plant cells central vacuole has many functions such as organic compound reserve, disposal site, pigment storage, poison storage, etc.

MitochondriaThe site of cellular

respiration (creates energy from food)

Has two membranesHas DNAFun fact – there are

lots of mitochondria in your muscle cells and you can increase the amount with exercise

ChloroplastsThe site of photosynthesisCreates organic molecules that can be

broken down in the mitochondriaThey are not found in animal cells

CytoskeletonFunction

SupportMotility Regulation

TypesMicrotubulesMicrofilamentsIntermediate

Filaments

MicrotubulesStructure

Hollow rods constructed from tubulin dimers (protein with two subunits)

FunctionAid in shape, support

and form tracks which organelles move along

Examples : Centrosomes and cilia and flagella

How a cilia or flagellum worksD:\Chapter_06\

C_Animation_and_Video_Files\06_Animations\06_24CiliaFlagella_A.swf

MicrofilamentsStructure

Solid rods built from twisted actin chains (smallest)

FunctionBears tension

helps support the cell’s shape

Movement Contraction of muscle

cells Amoeboid movement

Microfilaments – muscle contraction

Microfilaments – amoeboid movement

Amoeba moving

Structure Proteins coiled into

thicker cablesBigger than

microfilaments but smaller than microtubules

Function Tension bearing

Permanent fixtures of cells (do not move)

Intermediate Filaments

Check for understandingCell parts checklist

Contrast cell types As you are doing the worksheet, review the

function of each organelle with your group

DiffusionThe movement of molecules from an area of

higher concentration to an area of lower concentration

What determines whether a substance will enter or leave a cell?

Diffusion LabWill substances move through the

membrane?What determines which substances will

move?

Check for understandingDefine diffusionWhat types of molecules could move freely

through a cell membrane?

Demo with potatoe

MembranesKnow the parts of the cell membrane and

what the function is

MembranesFunction

Acts as a barrier that separates the inside and outside of the cell

Regulates the “traffic” of molecules into and out of the cell

MembranesStructure

Lipids and proteinsAmphipathic

(hydrophilic and hydrophobic regions)

Fluid mosaic model

For the following that are circled: Give the name and at least three facts, including the function

Two types of movement through the membranePassive transport – Does not need energy to transport

Active transport – Uses energy to transport

Something to ponder…Most fish are not able to move between salt

water and fresh water. Why do you think this is?

Osmosis labBe able to define osmosisDetermine which way water will move given

certain solute concentrations

OsmosisThe diffusion of water

across a selectively permeable membrane.Ex. Lettuce and salad

dressingOr wilted lettuce in

water

Water balance in cells

Check for understandingDraw a representation of the concept of

osmosis. (Hint: You may want to draw solutes to one side of a membrane and show which way the water is moving)

Water PotentialRead exercise 1C in lab notebook

Water potential is the potential for water to do work, or move out of the cellΨ = Ψp + ΨsWater potential equals the pressure potential plus the

solute potential.Increasing the pressure increases water potential (+)Increasing solutes decreases water potential (-)

Check for understandingIf a plant cell has a lower water potential

than its surrounding environment and if pressure is equal to zero, is the cell hypertonic (in terms of solute concentration) or hypotonic to its environment? Will the cell gain water or lose water?