Cell Biology - Test 2

Plasma Membrane

The outer boundary of the cell (5-10nm thick).

Three Main Types of Membrane Lipids

Phosphoglycerides, Sphingolipids, and Cholesterol.

Glycosylation

The addition of carbohydrates to a molecule.

Transmembrane

Passes through the bilayer and has domains of both sides.

Amphipathic

Has hydrophilic and hydrophobic regions.

Transition Temperature

The temperature at which the membrane changes states.

Flippases

Enzymes that move phospholipids from one leaflet to another.

Influx

Movement into the cell.

Efflux

Movement outside of the cell.

Net Flux

The difference between influx and efflux.

Passive

Does not require energy

Bilayer Diffusion

The movement of a lipid or molecule from one leaflet of a lipid bilayer to the opposite leaflet.

Osmosis

Diffusion of water across a membrane.

Ion Channel Diffusion

The movement of charged ions (Na, K, Ca, and Cl) across a cell membrane through protein channels down an electrochemical gradient.

Voltage-Gated Ion Channels

Depend on the charge differences.

Ligand-Gates Ion Channels

Depend on the binding of a specific ligand (molecule).

Mechano-Gated Ion Channel

Depends on the mechanical forces applied to the membrane.

Facilitated Diffusion

The movement of molecules or ions across a membrane from an area of higher concentration to and area of lower concentration, through integral membrane proteins.

Active Transport

The movement of molecules or ions across a membrane from an area of lower concentration to an area of higher concentration. (Against the concentration gradient).

Active

Requires energy from couple reactions.

Cotransport

A membrane protein moves two substances at the same time.

Symport

Two substances move in the same direction.

Antiport

Two substances move in opposite directions.

Neurons

Specialized cells for information transmission using changes in membrane potential.

Dendrite

Branched extensions of a neuron that receive incoming signals from other neurons.

Cell Body

Contains the nucleus and metabolic center.

Axon

Long extension of the neuron that conducts outgoing signals.

Resting Potential

The different in charge inside versus outside the cell.

Action Potential

The rapid temporary reversal of charge on the two sides of a membrane.

Saltatory Conduction

The rapid transmission of action potentials that "jump" from one gap to the next along a myelinated axon.

Synapse

A junction between a neuron and a target cell.

Neurotransmitters

Chemicals that act on postsynaptic cells.

Glycolysis

A metabolic pathway that splits one 6-carbon glucose molecule into two 3-carbon pyruvate molecules inside the cells cytosol.

Outermembrane

A protective barrier that separates the inside of the cell from the outside. It also controls what move into and out of the cell.

Intermembrane Space

The fluid filled compartment between the outermembrane and the inner membrane of the cell. Stores and produces ATP (energy), folds proteins, and performs apoptosis.

Inner Membrane

Houses the electron transport chain and generates chemical energy for the cell.

Cristae

Increases the cells area to maximize cellular energy production.

Cellular Matrix

A network of protein, glycoproteins, and carbohydrates that surrounds and supports cells.

Mitochondria

Produces ATP, synthesizes amino acids and heme groups, uptakes and releases Ca2+ in the cell, and regulates apoptosis.

Mitochondrial Inheritance

The transmission of genetic material located inside the mitochondria. Has maternal lineage only, and no mendelian patterns.

Aerobic Respiration

Cellular metabolism that breaks down glucose to generate energy without using oxygen; glycolysis, fermentation, TCA cycle, Oxidative Phosphorylation, the Electron Transport Chain, and ATP Synthesis.

Flavoproteins

Carries 2 electrons and 2 protons.

Cytochromes

Carry 1 electron.

Copper Atoms

Carry 1 electron.

Ubiquinone

Carries 2 electrons and 2 protons.

Iron-Sulfur Proteins

Carries 1 electron.

Electron Transport Chain

A series of four large protein complexes and carrier molecules in the mitochondria/plasma membrane that drives phosphorylation.

Electrochemical Gradient

A gradient containing both a concentration and electrical component.

Rotary Catalysis

A mechanism where physical, mechanical rotation of protein subunits inside an enzyme drives chemical reactions.

Uncoupling Proteins

Move protons back to the matrixPeroxisomes without producing energy.

Peroxisomes

Small membrane-bound vesicles that contain oxidative enzymes. Breaks down hydrogen peroxide, oxidative metabolism, and forms by splitting from preexisting organelles.

Glyoxysomes

Specialized peroxisomes found in plant seedlings.

Heterotrophs

An organism that consumes other plants, animals, or organic matter for energy and nutrients.

Autotrophs

Manufacture organic nutrients from CO2 and H2S.

Photoautotrophs

Use radiant energy to make organic compounds.

Photosynthesis

The biochemical process by which plants convert sunlight , water and carbon dioxide, into glucose and oxygen.

Chloroplasts

Conducts photosynthesis in plant cells.

Thylakoids

Flattened sacs in the chloroplast of a plant cell.

Grana

Stacked sacs in the chloroplast of a plant cell.

Lumen

The space inside of a thylakoid.

Stroma

The space outside the thylakoid but within the chloroplast envelope.

Light Dependent Reactions

Sunlight is absorbed and converted into ATP and NADPH

Light-Independent Reactions

Use energy stored in ATP and NADPH to produce carbohydrates.

Chromoplasts

A family of plastids whose primary function is to be colorful.

Light Harvesting Antenna

Captures light in the inner membrane of a plant cell.

Photolysis

The splitting of water during photosynthesis.

Photoinhibition

A negative effect of high intensity light on the performance of photosystem 2.

Photophosphorylation

ATP production associated with the formation of oxygen.

Calvin Cycle

A series of light-dependent chemical reactions in photosynthesis that turns CO2 into glucose.

Rubisco

An enzyme that convert inorganic carbon dioxide into organic molecules.

CAM Pathway

A photosynthetic adaptation that allows plants to save water in hot, dry environments by separating carbon fixation and the Calvin cycle by time rather than space.