Cells and Cell Transport Notes for Test 12/11

List the 3 types of passive transport.

- diffusion - facilitated diffusion - osmosis

List 3 types of bulk transport.

- endocytosis - exocytosis - phagocytosis or pinocytosis (part of endocytosis)

List the 3 conditions of osmosis.

- hypertonic solution - hypotonic solution - isotonic solution

List 2 types of active transport.

- protein pumps - sodium (Na+) / potassium (k+) pump

What is the function(s) of the cell membrane?

- regulates what enters and leaves the cell (selectively permeable / selective barrier) - protecting and supporting the cell - selectively permeable/regulates what enters and leaves the cell

Cell theory

1. All living organisms are composed of one or more cells. 2. Cells are the basic unit of structure and organization of all living organisms. 3. Cells arise only from previously existing cells, with cells passing copies of their genetic material on to their daughter cells.

What are the two functions of lysosome?

1. Phagocytosis lysosome digesting food - Through the food vacuole, hydrolytic enzymes digest food particles 2. Autophagy - self-eating; break down and recycle old (damaged) organelles - Lysosome fuses with vesicle (with damaged mitochondria (lots of lipids and proteins))

Levels of Cellular Organization

Cells → tissues → organs → organ systems → organisms • Cells - basic unit of structure and function of all living things Ex. muscle cell • Tissues - group of cells of the same kind Ex. smooth muscle tissue • Organs - structure composed of one or more types of tissues Ex. stomach • Organ systems - group of organs that work together to perform a certain function (10 organ systems) Ex. digestive system • Organisms - individual living things that may be made up of one or more organ systems Ex. human

How are channel, integral, and peripheral proteins different? How are they similar?

Different: peripheral proteins are surface proteins and on the edge / being inside/outside of the cell, while integral proteins span the whole membrane and channel proteins transport molecules across a cell membrane Similar: they all revolve around a lipid bilayer

True or False: In PASSIVE TRANSPORT, the movement of particles across a membrane requires energy.

False ; active

True or False: The passive transport of material across a membrane by means of transport proteins is called ACTIVATED DIFFUSION.

False ; facilitated diffusion

True or False: A solution in which the concentration of dissolved substances is lower than the concentration inside the cell is HYPERTONIC.

False ; hypotonic

Into what organelle is protein secreted when complete?

RER

Cytoplasm

Structure: - (everything) outside nucleus (nuclear envelope), inside cell membrane - cytosol (fluid/H2O) + organelles Function(s): - gives cell shape - supports internal structure - stores vital chemicals

Mitochondrion

Structure: - 2 PLB - curves in inner membrane → higher SA - fluid filled - has inner and outer membrane (lipid bilayers) - inner membrane is folded and has proteins - has fluid inside Function(s): - a membrane-bound organelle that makes energy available to the rest of the cell - convert the chemical energy stored in food into compounds that are more convenient for the cell to use Found in: - eukaryotes

Cytoskeleton

Structure: - 3 proteins: - microfilament (made of protein actin) - intermediate filaments (made of keratin protein) - microtubules (hollow tubes made of protein tubulin) Function(s): - a framework for the cell within the cytoplasm - supports and helps the cell maintain its shape - involved in movement and cell division Found in: - eukaryotes

Nucleolus

Structure: - darkened region in the nucleus containing nucleic acids (rRNA) Function(s): - where the assembly of ribosomes begins

Cell wall

Structure: - made of cellulose in plants (carb - structural polysaccharide) - located outside the cell membrane Function(s): - an inflexible barrier that provides support and protects the plant cell - supports, shapes, and protects the cell Found in: - prokaryotes, plant, fungi

Flagellum

Structure: - made of protein - microtubules (9+2 arrangement) - long, whip like; few - longer appendage on cell surface Function(s): - projections that aid in locomotion and feeding - cell motility in fluid environments, whipping motion Found in: - animal, plant, prokaryotes

Cilia

Structure: - made of proteins - microtubules (9+2 arrangement) - short-hair like; numerous - short and numerous on cell surface Function(s): - projections from cell surfaces that aid in locomotion and feeding; also used to seeep substances along surfaces - cell motility in fluid environments, beating motion Found in: - animal, fungi, plant

Ribosomes

Structure: - made of rRNA + protein - free floating (in cytoplasm) or bound (attached to ER) Function(s): - organelle that is the site of protein synthesis - assemble proteins Found in: - all cells

True or False: A membrane that allows only some materials to pass through shows SELECTIVE PERMEABILITY.

True

True or False: ENDOCYTOSIS is a process by which a cell membrane surrounds and takes in material from the environment.

True

True or False: The internal pressure of a plant cell is called TURGOR PRESSURE.

True

Dynamic Equilibrium

a point in which once equilibrium is reached, molecules will continue to move randomly • molecules move in/out at the same rate keeping the concentration about the same in/out of the cell (red-pen edit) • continuous movement of particles but no overall change in concentration

An amoeba engulfs a particle of food:

a. Does this require energy? - yes (moving) b. Is this active or passive transport? - active c. Is this endocytosis or exocytosis? - endocytosis d. Is this phagocytosis or pinocytosis? - phagocytosis

An amoeba expels waste:

a. Does this requires energy? - yes b. Is this active or passive transport? - active c. Is this endocytosis or exocytosis? - exocytosis

Plant cell after being overwatered:

a. Water rushes into the plant cell's vacuole. Is this diffusion or osmosis? - osmosis b. Is this passive or active transport? - passive c. What is the force called that causes water to rush into the plant cell? - osmotic pressure d. Does turgor pressure increase or decrease? - increase e. Is the plant cell in a hypertonic, hypotonic, or isotonic environment? - hypotonic (water is rushing into higher concentration) f. What will more likely occur to the cell if this continues, plasmolysis or cytolysis? - neither - plants don't burst because of cell wall protection

Plant cell after not being watered lately, so it has begun to wilt:

a. Which way will the water go? Into the vacuole, or out of the vacuole? - out b. By what process will the water move? - osmosis c. Does turgor pressure increase or decrease? - decrease d. Is the plant cell in a hypertonic, hypotonic, or isotonic environment? - hypertonic e. What will more likely occur to the cell if this continues: cytolysis or plasmolysis? - plasmolysis (plasma pulls away from cell wall)

A cell surrounded by blood (blood plasma is about 90% H2O):

a. Will water move from the blood to the cell, or from the cell to the blood? - blood to the cell b. Which has the higher concentration of water, the cell or the blood? - blood c. Does this require energy? - no d. Is this active or passive transport? - passive e. Is this diffusion or osmosis? - osmosis f. Does the blood cause a hypotonic or hypertonic environment for the cell? - hypotonic (lower concentration of solute on outside) g. What will more likely occur to the cell if the movement of water continues in the same direction: plasmolysis or cytolysis? - cytolysis

Chloroplast

carries out photosynthesis Structure: - 2 PLB - stack of discs (PLB) - higher SA - thylakoids - have pigments - fluid-filled - has an inner and outer membrane (lipid bilayers) - has stacks of thylakoids (disc-shaped formed by lipid bilayers) with proteins and pigments) - has fluid inside Function(s): - a double-membrane organelle with thylakoids containing chlorophyll; where photosynthesis takes place - capture E from sunlight and convert it into food that contains chemical energy in a process called photosynthesis Found in: - plant, fungi

Bulk Transport

cells take in or release very large particles or dissolved solutes through movement of the cell membrane (requires energy (due to cell movement)) - movement of macromolecules

What is the function of glycoproteins in the cell membrane?

glycoproteins - span the whole membrane and are transmembrane/integral proteins • recognize cell to cell interaction/binding • cell ID

If it is not watered, a tulip plant wilts because it ...

loses turgor pressure

Plasmolysis

loss of water from a cell resulting in a drop in turgor pressure

How does the concentration gradient flow in diffusion?

moves from an area of high concentration to an area of low concentration until they're equally distributed on both sides/parts of the membrane • high to low

How are particles moved in and out of a cell during facilitated diffusion?

moving from high to low concentration through a protein channel in the membrane • protein channels/carriers

In order, list the organelles that are involved in making proteins.

nucleus (DNA → RNA) → RNA to ribosome = protein → (RER) vesicle → Golgi apparatus → cell membrane/other destinations

If a cell is placed in salt water, water leaves the cell by ...

osmosis

Cell membrane

part of endomembrane system (made of PLB) Structure: - (phospho)lipid bilayer, proteins, carbohydrates, and cholesterol Function(s): - selective barrier - leave cells - sep. inside/outside of cell - regulates what enters and leaves the cell - protects and supports the cell - selectively permeable: some substances can pass through and others can NOT Found in: - all cells

Vacuoles/Vesicles

part of endomembrane system (made of PLB) Structure: - PLB - vesicles - small membrane, enclosed sacs - food vacuole - H2O filled - central vacuole - Central vacuole: - enclosed membrane (lipid bilayer) filled with water, ions, and enzymes (proteins) - Vesicles: - small enclosed membrane - Food vacuole: - enclosed membrane (lipid bilayer) with macromolecules inside Function(s): - a membrane-bound vesicles for the temporary storage of materials - Central Vacuole: store materials like H2O, salts, proteins, and carbohydrates. Provides pressure and support to cells and the entire plant. - Food vacuole: carries food/macromolecules to the lysosome for digestion by enzymes - Vesicles: - stores and moves materials between cell organelles and to cell surface - may contain vital chemicals or macromolecules Found in: - plant, animal

Rough ER

part of endomembrane system (made of PLB) Structure: - PLB w/ ribosomes attached - contains enzymes (proteins) - has ribosomes attached that insert protein inside RER Function(s): - carries proteins assembled by ribosomes to be transported out of the cell to become part of the cell membrane or to become enzymes within the ribosome or to other locations within the cell Found in: - eukaryotes

Lysosomes

part of endomembrane system (made of PLB) Structure: - PLB — membrane enclosed sac (full of enzymes) Function(s): - a vesicle that contains digestive enzymes for the breakdown of excess or worn-out cellular substances - breaks down lipids, carbohydrates, and proteins into small molecules that can be used by the rest of the cell - break down old or damaged organelles and recycle monomer units Found in: - animal, plant

Golgi Body/Appartus

part of endomembrane system (made of PLB) Structure: - PLB — stack of flattened membrane sacs (pita bread) Function(s): - a flattened stack of tubular membranes that modifies proteins and packages them for distribution outside the cell - modifies, sorts, and packages proteins and other materials form the ER for storage in the cell or release outside the cell Found in: - eukaryotes

Nucleus

part of endomembrane system (made of PLB) Structure: - double PLB + pores - made of protein - DNA → chromosomes - nuclear envelope: lipid bilayers with pores - contains chromosomes (DNA + protein) Function(s): - the control center of the cell that contains coded directions for the production of proteins and cell division - controls and coordinates the activities of cells Found in: - eukaryotes

Smooth ER

part of endomembrane system (made of PLB) made of lipids Structure: - PLB - no ribosomes (attached) - enzymes inside Function(s): - makes (membrane) lipids - detoxifies drugs/alcohol - release Ca ++ (calcium) for muscle contraction - lots in liver Found in: - eukaryotes

What is the structure most responsible for maintaining cell homeostasis?

plasma membrane - made up of a lipid bilayer

What happens to proteins while in the Golgi?

proteins are modified, packaged, and shipped

Where do proteins go when they leave the Golgi?

proteins go to the cell membrane or to different destinations

What organelle make proteins by reading RNA?

ribosomes

Contractile Vacuole

structure inside protists (paramecium) that collects excess water and squeezes it outside through the membrane

Osmosis

the diffusion of water through the membrane; H2O moves to dilute the higher (total) concentration of solute • diffusion of water molecules through a selectively permeable membrane

Passive Transport

the movement of molecules from high to low concentration across the membrane without energy (no ATP required)

Active Transport

the movement of molecules from low to high concentration across the membrane with energy (upstream / against concentration gradient)

Diffusion

the process by which particles move from an area of high concentration to an area of low concentration - the movement of small, uncharged, non-polar molecules across the lipid bilayer (PLB) - ex. H2O, ammonia (NH3), CO2, O2 - lipid-soluble substances (hydrocarbon) can undergo diffusion - water-soluble substances (glucose) and ions (charged) can NOT undergo diffusion • movement of particles from an area of higher concentration of to one of lower concentration • continues until equilibrium is reached

Facilitated Diffusion

the process in which molecules cannot move through the lipid bilayer because the molecules are too large or charged must use protein channels or carrier proteins (helper proteins) -glucose moves from high to low concentration through a protein channel in the membrane

Endocytosis

the process of taking material into the cell by means of folding of the cell membrane - phagocytosis: the cell engulfs large food molecules and brings them in as a food vacuole - cells take in food - pinocytosis: the cell engulfs fluid with dissolved solute and brings them in as a vesicle - cellular drinking • large macromolecules "entering" cell

In diffusion, particles move according to what concentration?

their own individual concentration gradients

Protein Pumps

transport proteins carry small molecules or ions across the membrane against the concentration gradient (low to high) - in example, cell needs more glucose / it moves more glucose into a cell

How are proteins transported to the Golgi apparatus?

vesicles

Exocytosis

when waste products or other large materials exit the cell as a vesicle by budding out of the cell membrane • large amounts of waste (red-pen edit) • release of wastes or cell products from inside to outside a cell

Which direction does water move in osmosis?

where there is a high concentration of solute and a low concentration of water

What is the structure of the cell membrane?

• a PLB, proteins, carbohydrates, and cholesterol (part of the endomembrane system) • phospholipid bilayer, proteins

Differentiate between active and passive transport.

• active - requires E ; low to high • passive - no E required ; high to low

What is the difference between free and bound ribosomes?

• bound ribosome - bound to the ER • free ribosome - floating in the cytoplasm

How are carrier and channel proteins similar and different?

• carriers (specific) change shape -(carries)-> ions (used in active and passive transport) • channels (non-specific) - funnels; carries large molecules (used in passive transport)

Sodium (Na+) / Potassium (k+) Pump

• cells pump three sodiums for every two potassiums - is w/ membrane proteins - if sodium goes out, phosphate goes in - generates nerve impulse

Fluid (motion) Mosaic Model

• channel protein - transports molecules across a cell membrane • peripheral protein - randomly dispersed; on the edge / "surface proteins" and in/outside of cell • integral protein - transmembrane protein; spans the whole membrane

Hypertonic Solution(s)

• contain a high concentration of solute relative to another solution (e.g. the cell's cytoplasm); when a cell is placed in a hypertonic solution, the water diffuses out of the cell, causing the cell to shrivel (animals)/plasmolyze (plants) - high amount of energy → more concentration outside - in plants, plasmolysis can occur, in which the cell membrane shrinks away from cell wall

Hypotonic Solution(s)

• contain a low concentration of solute relative to another solution (e.g. the cell's cytoplasm); when a cell is placed in a hypotonic solution, the water diffuses into the cell, causing the cell to swell and possibly explode (plant cell won't) - solute would move out, but H2O would move in - more concentration inside - in plant cell, cytoplasm pushes against the cell membrane with turgid (turgus pressure allows plant to stand up) - in animal cell, there is no cell wall to protect the cell, so it can lead to lysis (bursting) / cell death

Isotonic Solution(s)

• contain the same concentration of solute as another solution (e.g. the cell's cytoplasm); when a cell is placed in an isotonic solution, the water diffuses into and out of the cell at the same rate; the fluid that surrounds the body cells is isotonic - in a plant cell, it prefers a hypotonic solution, so with no pressure, it becomes wilted/flaccid - in an animal cell, both hypotonic and isotonic is accepted, so it's normal

Differentiate between diffusion and facilitated diffusion.

• diffusion - goes through lipid bilayer (small/uncharged) • facilitated diffusion - uses protein channels/carriers (large/charged)

Eukaryotes

• has a nucleus • has membrane-bound organelles • larger than prokaryotes and more complex • single-celled or can be multicellular • multiple linear chromosomes • specialized and complex compartments • include plant cells, animal cells, fungal cells, protist cells

Both prokaryotes and eukaryotes

• have uni-cellular organisms • have plasma membrane • have DNA • grow • have ribosomes • have cytoplasm • cell membrane • reproduce and respond to environment • some are motile and some aren't

Prokaryotes

• no nucleus (no nuclear membrane (no membrane around DNA)) • no membrane-bound organelles • smaller than eukaryotes and simple • single-felled • single circular chromosome • include bacteria

Differentiate between osmosis and diffusion.

• osmosis - movement of H2O • diffusion - movement of solutes