U2 Ch3 Cellular Level

potassium

increased concentration inside cell

sodium

increased concentration outside cell

selective prmeability restricts materials based on

size, electrical charge, molecular shape, lipid solubility

Lipid solubility regarding cell membrane

non polar can pass easier than poler or ionic compounds

Diffusion

NO ENERGY. Movement of substances from area of HIGH concentration to area of LOW concentration.

Factors influencing diffusion

distance particle has to move, molecule size, temp, concentration gradient, electrical forces

Simple diffusion

materials diffuse directly through plasma membrane (lipid soluable and on polar) Ex: fatty acids, alcohol, o2, co2, steroids, triglycerides.

Channel Mediated

concentration gradient drives movement of solute through a transmembrane channel protein. NEEDS SPECIFIC CHANNEL PROTEIN. Moves polar substances: glucose, ions, amino acids.

Osmosis

Movement of WATER from area of HIGH concentration to area of LOW concentration through a membrane.

Aquaporins

A transport protein in the plasma membrane of a plant or animal cell that specifically facilitates the diffusion of water across the membrane

200 mOsm or less

Cell will take on fluid. Net movement INTO cell. Cell gains volume-swells-LYSE. (Hypo=swells)

400 mOsm

Water will leave cell. Concentration of solution is greater so net movement of water OUT of cell. CRENATING

overhydration

decreased mOsm

Dehydrated RBC

crenate

Overhydrated RBC

Lyse

Facilitated Diffusion

NO ENERGY Movement of specific molecules across cell membranes through protein channels (glucose, amino acids)

sodium potassium pump

1 ATP moves 3 sodium out and 2 potassium in

sodium potassium pump

Actively moves Na+ out of cells and moves Ka+ in

Endocytosis

The process by which a cell membrane surrounds a particle and encloses the particle in a vesicle to bring the particle into the cell

Pinocytosis

Cell drinking

Phagocytosis

Cell eating
A type of endocytosis in which a cell engulfs large particles or whole cells

Exocytosis

Process by which a cell releases large amounts of material EXITS CELL

mitosis

A type of cell division that results in two daughter cells each having the same number and kind of chromosomes as the parent nucleus, typical of ordinary tissue growth.

cytokinesis

Division of the cytoplasm during cell division

interphase

Cell grows, performs its normal functions, and prepares for division; consists of G1, S, and G2 phases

prophase

Chromosomes become visable, nuclear envelop dissolves, spindle forms

metaphase

Chromosomes line up in the middle of the cell

anaphase

Phase of mitosis in which the chromosomes separate and move to opposite ends of the cell

telephase

chromosomes uncoil into chromatin, nuclear membrane forms, the nucleolus reappears

DNA Polymerase

Enzyme involved in DNA replication that joins individual nucleotides to produce a DNA molecule

RNA Polymerase

Enzyme that links together the growing chain of RNA nucleotides during transcription using a DNA strand as a template

Helicases

unwind DNA strands

mutation

permanent change in the sequence of base nucleotides