AP Bio Unit 2: Cell Structure and Function

A solution in which the concentration of solutes is greater than that of the cell that resides in the solution

A solution in which the concentration of solutes is equal to that of the cell which resides in the solution

A solution in which the concentration of solutes is less than that of the cell that resides in the solution

Hypotonic to hypertonic

Diffusion of free water across a selectively permeable membrane

surface area to volume ratio (ex. 12:1)

efficient exchange of material with the environment

increase; decreases

Cells need room for organelles

Molecules that contain both hydrophilic and hydrophobic properties (phospholipids)

Model that describes the arrangement and movement of the molecules that make up a cell membrane

decreases

increases

Movement of molecules from high to low concentration WITHOUT metabolic energy (ATP)

polar to protect polar molecules that come through

Free movement of small, nonpolar molecules from high to low concentration (ex. N2, O2, CO2)

Movement of larger, polar, and/or charged molecules from high to low concentration through transport proteins; Allows for hydrophilic molecules to pass through membranes (ex. glucose, urea, K⁺, Na⁺, Cl⁻)

The physical property predicting the direction in which water will flow, governed by solute concentration and applied pressure.

Ψ = Ψs + Ψp

Ψs = -iCRT

ionization constant (ex. sucrose/glucose = 1, sodium chloride = 2)

molar concentration

0.0831

temperature in kelvin (273 + C°)

0

less negative; more negative

high; low

Aquaporins

increase

against

ATP→proton pump→H⁺ ions→cotransporter→sucrose (moved by cotransporter)

Ability to do work

Hydrophilic tunnels in the cell membrane that allow larger, polar, and/or charged molecules to pass through

Membrane structures that change shape to move target molecules from one side of the cell membrane to the other

performed

2

Total solute concentration in a solution

The measurement of the relative concentrations of solute between 2 solutions (in and out of cell)

2 (a cell has to be hypo/hyper/isotonic to a solution and vice versa)

osmosis

One or more carb attached to a membrane protein

Phospholipids with a carb attached (communication)

Free: float in cytosol and produce proteins for it Bound: attached to the ER, produce proteins that will be a part of the membrane, or enclosed in it

A non-membrane-bounded region in a prokaryotic cell where the DNA is concentrated

Lipid synthesis, detoxification, carb metabolism, NO ribosomes on its cytoplasmic surface (liver cells have lots because they host glycolysis and are the site of alcohol detoxification)

Has ribosomes on its cytoplasmic surface

nucleolus

Proteins, lipids, and other macromolecules are sent her to be modified by the addition of sugar and other molecules to form glycoproteins

storage diseases

When an enzyme used to digest lipids is absent, leading to excessive accumulation of lipids in th ebrain

Organelle that contains enzymes that produce hydrogen peroxide as a by-product while performing various functions, such as breakdown of fatty acids and detoxification of alcohol in the liver; also contain an enzyme that converts the toxic hydrogen peroxide by-product of these reactions into water

A network of fibers that provide support, shape, and mobility

Microtubules, microfilaments, and intermediate filaments

Constructed from tubulin and help in cell division and are in cilia and flagella

Constructed from actin and help in muscle contraction

Constructed from keratins (proteins) and help in shape and position of organelles

centrioles

homeostasis

Collapse of a walled cell's cytoplasm when the cell is in a hypertonic solution and water leaves

Process in which substances are brought into the cells by the enclosure of the substance into a membrane-created vesicle that surrounds the substance and escorts it into the cell (used by immune cells called phagocytes)

Process in which substances are exported out of the cell when a vesicle escorts the substance to the plasma membrane, causes it to fuse, and ejects the substance outside

Process of bringing in droplets of extracellular fluid via tiny vesicles

Cell takes in large particles

Phagocytosis, pinocytosis, and receptor-mediated endocytosis

Specialized type of pinocytosis that moves specific molecules into a cell due to the budding of specific molecules with the receptor sites on the cell membrane

Cell wall, membrane, ribosomes

vesicles in a cell

A carrier protein that uses ATP to actively transport 3 Na⁺ ions out of a cell and 2 K⁺ ions into the cell to maintain the membrane potential

the sodium and potassium concentration gradients will dissipate, and so will the membrane potential

An electrical potential difference (voltage) across their cell membrane

Minimizes competing reactions, provides a favorable environment for specific reactions, and help protect the cell from potentially hazardous products from certain reactions

Prokaryotes formed symbiotic relationships with larger cells (endosymbiosis)