AP BIO Unit 2 comprehension

What is the function of the Plasma membrane

borer between the cell and the outside regulating what enters and exits the cell

What is the function of the Cytoplasm

interior of the cell consisting of water where ions enzyms and small molecules can be dissolved and glycolysis takes place

What is the function of the Vesicle

A membrane-enclosed sac that transports materials throughout the cell

What is the function of the Rough ER

distributes proteins produced by the ribosomes on its surface

What is the function of the Smooth ER

Produces lipids and detoxifies poisons

What is the function of the Golgi apparatus

receives proteins and lipids from the ER, then modifies them (it’s like the packaging center), afterwards ships them off to where they are going next in the cell

What is the function of the lysome digestive

center of cell that breaks down wastes of damages cell parts

What is the function of the vacuole

stores materials in the cell

What is the function of the Mitochondria

carries out cellular respiration producing engery for the cell

What is the function of the cytoskeleton

Supports the shape of the cell and anchors organelles. Its made of variouse proteins

What is the function of the microtubules

“Roads“ for motor proteins to transport vesicles used for movements of cells

they help for divison making up the spindle

What is the function of the Microfilaments

used in muscle contraction, they are the thinnest components of the cytoskeleton

What is the function of the Intermediate filaments

provide the shape and strucutre for the cell

What is the function of the DNA

Directs the activities of the cell and has the code for the production of proteins

Describe: Nuclear envelope

has a double membrane around the nucleus, sperating genetic material from the cytoplasm

Describe: Nuclear Pore

Small holes that punctuate the nuclear envelope are formed by a ring of proteins. They act as a bridge between the inner and outer membranes of the nuclear envelope.

Describe: Nucleoli

Dense, nonmembrane-bound structure within the nucleus of a eukaryotic cell, responsible for producing and assembling ribosomes.

Describe: Ribosomes

Small, non-membrane-bound cellular structures with ribosomal RNA (rRNA) and proteins that synthesize polypeptides. they function as protein synthesis building proteins

Describe: Endomembrane System

Network of interacting membrane-bound organelles in Eukaryotic cells that work together to synthesize modify, package and transport proteins and lipids; How differnt organells work together to make the cell function

Describe: Vacuoles

large membrane bound sacs inside eukaryotic cells that handel storage wast disposal and osmotic balance

Describe the structure of the Mitochondria: outer and inner membranes, cristae, matrix, and intermembrane space

The outer membrane, a protective boundary covering the organelle, has channel proteins called porins, which make it possible for small molecules and ions to enter/exit

Intermembrane space: narrow fluid-filled region between the inner and outer membranes

Inner membrane, highly folded (increases surface area), strictly regulates what enters the matrix

Cristae, inward folds and invaginations of the inner mitochondrial membrane

Matrix, gel-like fluid compartment completely enclosed by the inner membrane

Describe the structure of the Chloroplasts: outer and inner membranes, thylakoids, grana, and stroma

Outer membrane- protective barrier that regulates the movement of molecules in and out

Inner membrane- located right beneath the outer membrane; it provides an even more selective barrier

Thylakoids- flattened, coin-like membrane-bound sacs inside the stroma whose membranes contain chlorophyll and host the light-dependent reactions of photosynthesis. The fluid-filled interior of a thylakoid is called the lumen

Grana- interconnected stacks of thylakoid discs. Increases surface area available for light absorption

Stroma- dense gel-like fluid matrix surrounding the thylakoids and enclosed by the inner membrane

Describe: Extracellular matrix

complex meshwork of proteins and carbohydrates secreted by animal cells provoiding strctural and biochemical support to surrounding tissues

Describe: Endosymbiotic Theory

Mitocondria and chlorplasts are derived from bacterial cells that were engulfed in larger cells

they arose from infolding of the cell membrane

big cells ate the little cells

What are three unit Plant cell features?

1. Cell wall (cellulose)

2. Choroplast

3. Vacuole

What are the similarities between prokaryotic and eukaryotic cells?

• Plasma membrane

• cytoplasm/cytosol

• DNA

• Ribosome

What are the differences between prokaryotic and eukaryotic cells?

• Prokaryotic cells have no nucleus, so the DNA is uncontained in an open nucleoid region

• Prokaryotic DNA is small and circular

• Eukarotic has a “true nucleus“

• Eukaryotic has predent membraned bound organelles (ex Golgi, mitochondria, chloroplasts)

• Eukaryotic can be unicellular or multicellular

What are the evolutionary relationships between prokaryotic and eukaryotic cells?

Endosymbiotic theory, where pretty much the bigger cells ate the little cells

How does compartmentalization organize a cell’s functions?

using internal membranes and membrane-bound organelles, increased surface area for reactions (that’s why there is folding in the cell) (add more on later)

How are the structures of the various subcellular organelles related to their functions?

Directly adapted to maximize the efficiency of their cellular function, for example, their specialized Compartmentalization and surface area will be specific to their function

How do organelles function together in cellular processes?

The endomembrane system (protein synthesis and transport) there are differnt organelles, which have different jobs; For example, the nucleus stores DNA, and vesicles carry proteins from the RER to the Golgi apparatus.

What factors limit the cell size?

The surface area to volume ratio dictates how efficiently a cell exchanges materials within its environment

Describe the membrane structure

1. Phospholipids make a membrane bilayer

   1. The head is hydrophilic

   2. The tail is hydrophobic

2. Proteins are integrated into the membrane; they aid in transport, act as enzymes, facilitate cell-to-cell communication, and are used to anchor cells to one another or other surfaces

   1. The ones on the top are called peripheral membrane proteins

   2. The ones in the membrane are called integral membrane proteins

3. Minor components

   1. glycocalyx (glycoproteins and glycolipids): they are the layer of sugar groups outside the cells and are important for cell-to-cell recognition

   2. Cholesterol moderates the fluidity of the membrane

   3. Membrane fluidity how easily phospholipids and proteins move around within the bilayer

What factors influence membrane fluidity+ why/ what is membrane fluidity

Membrane fluidity is how flexible the cell membrane lipid bilyaer its. Factors that influence the fluidility is temperature; when it has a high temperature, there is an increase in energy to the membrane are more fluid, while low temperatures will cause the phospholipids to pack tightly together and become solid. In addition, temperature affects cholesterol; at warm temperatures, the cholesterol will restrain phospholipid movement and decrease fluidity, while at cold temperatures it disrupts tight packing and prevents the membrane from solidifying. Phospholipids that are unsaturated are kinky, so they are not able to be as tightly packed together as saturated phospholipids, which are straight and can be tightly packed together.

Describe selectively permeable what can’t enter the cell

Membranes only allow certain substances to enter or exit cells

• large molecules

• hydrophilic molecules (bc their polar)

• ions (bc they have a charge)

What is passive transport?

movement across the membrane that requires no engery

What is concentration gradient

difference in concentration across the membrane

describe Osmosis + auaporins

It’s the diffusion of water from a HIGH → LOW concentration

auaporins is protiens that allowd water to pass though the membrane

What is water potential?

Measures the tendency of water to move from one location to another

What always moves from a HIGH concentration to a

potiential of pure water is 0

Define the solute potential, the pressure potential and types of solutions (—hyper -hypo and -iso tonic )

Solute potential- increasing the amount of solute and decreasing the water potential

Pressure potential - increasing the pressure on the cell and increasing water potential

Hypertonic- high concentration of solute

Hypotonic- low concentration of solute

Isotonic- same concentration of solute

Describe activee