Shared Flashcard Set

Details

exm 3
vocab terms and key concepts
44
Biology
Undergraduate 1
10/19/2013

Additional Biology Flashcards

 


 

Cards

Term
energy
Definition
ability to do work
Term
potential energy
Definition

stored energy available to do work


 

Term
kinetic energy
Definition
energy being used to do work; any moving object posses kinetic energy
Term

kilocalorie

 

Definition
most common unit of measuring the energy content of food. kilocalori equals 1000 calories
Term
entropy
Definition
measure of randomness or dissorder
Term
metabolism
Definition
the sum of chemical reactions in a cell
Term
oxidation-reduction (redox) reactions
Definition
chemical reaction in which one reactant is oxidized and another is reduced
Term
oxidation
Definition
the loss of one or more electrons by a participant in a chemical reaction
Term
reduction
Definition
gain of electrons
Term
electron transport chain
Definition
membrane bound molecular complex that shuttles electrons to slowly extract their energy
Term
concentration gradient
Definition
- a difference in solute concentration between two neighboring regions. Gradients dissipate without energy input.
Term
passive transport
Definition
movement of a solute across a membrane without the direct expenditure of energy
Term
diffusion
Definition
the dissipation of a chemical gradient by random molecular motion
Term
simple diffusion
Definition
a substance passes through the membrane along its concentration gradient without the aid of a transport protein
Term
isotonic
Definition
condtion in which a solute concentration is the same on both sides of a semipermeable membrane
Term
hypotonic
Definition
describes a solution in which the solute concentration is less than on the other side of a semipermeable membrane
Term
hypertonic
Definition
describes a solution in which the solute conectration is greater than on the other side of semipermeable mebrane
Term
turgor pressure
Definition
the force of water pressing against the cell
Term
facilitated diffusion
Definition
-membrane protein admits a substance along its concentration gradient without expending energy
Term
active transport
Definition
a carrier protein uses energy (ATP) to move a substance against its concentration gradient
Term
sodium-potassium pump
Definition
uses active transport to exhchange sodium ions for potassium ions
Term
endocytosis
Definition
a cell engulfs liquids or large particles
Term
phagocytosis
Definition
bring in solid particles
Term
exocytosis
Definition
vesicles inside the cell carry substances to the cell membrane where they fuse with the membrane and realease the cargo inside
Term

Define potential and kinetic energy

Definition
Potential energy: is stored energy available to do work.
Kinetic energy: is energy being used to do work; any moving object possess kinetic energy.
Term

Express how potential and kinetic energy relate to thermodynamics (we discussed 2 laws)

Definition

first law:

-energy exists

-cannot be destroyed

-only converted to other forms

-energy transfomrations sustaining life are similar in all organisms

second law

-all transfomrations are efficent 

-some energy is lost as heat

 

Term

Define metabolism

Definition
the biochemical reaction of a cell
Term

Define endergonic and exergonic reactions

Definition
endergonic reaction - a reaction requiring a net input of free energy
exergonic reaction - a reaction that gives off free energy
*energy is being released or absorbed
Term

Discuss the difference between ADP and ATP, and describe how cells store energy in ATP

Definition
ADP-
ATP- A molecule whose high-energy phosphate bonds power many biological processes 
How cells store energy-
Term

Discuss the nature of enzymes

Definition
they lower the amount of energy required to start a reaction
Term

Label a process such as substrate + enzyme à enzyme-substrate complex à enzyme + product

Definition

substrate (the molecule undergoing a reaction) binds to the enzyme (the catalyst) forming intermediate complex; in intermediate complex the substrate is altered, then released from the enzyme as product; the enzyme, unchanged in the reaction, can then participate in another reaction with a substrate molecule. 

H2O + amylase + starch --> amylase-starch complex --> maltose + amylase.

Term

Define activation energy and how it relates to enzymes

Definition
the amount of energy that is required to start a reaction. And enzymes lower that amount of energy
Term

Define “selectively permeable”

Definition
membranes have the ability to admit only some substances
Term

Define concentration gradient

Definition
a solute is more concentrated in one reaction than in a neighboring region
Term

Define active and passive transport

Definition
active: movement of a substance across a membrane against its concentration gradient, using a carrier protein and energy from ATP
Passive: a substance moves across a membrane without the direct expenditure of energy.
Term

Define simple diffusion, osmosis, and facilitated diffusion

Definition
simple Diffusion:is a form of passive transport in which a substance moves down its concentration gradient without the aid of transport protein 
osmosis: Is the simple diffusion of water across a selectively permeable membrane 
Facilitated diffusion: is a form of passive transport in which a membrane protein assists the movement of a polar solute along its concentration gradient where it is more concentrated to where it is less concentrated
Term

Describe osmosis in the context of tonicity scenarios e.g. a red blood cell in hypo, iso, hyper..tonic solution

Definition
human red blood cell is isotonic to the surrounding plamsa. Water enters and leaves the cell at the same rate, and the cell maintains its shape. When the blood cell is in hyptonic solution it it when the salt concentration of the plasma decreases,water flows into the cell faster that it leaves. The cell swells and even bursts. When the cell is hypertonic it is in salty surroundings , the cell loses water and shrinks
Term

Describe the processes of endocytosis and exocytosis

Definition

endocytosis:It is a process, which involves intake of a substance due to a pushing in of the cell membrane.Two types of endocytosis is pinocytosis and phagocytosis.Exocytosis:It is the process in which materials either waste products or secretions are eliminated from a cell. The process involves the substance being surrounded by a membranous vacuole or vesicle. It moves to the surface of the cell and fuses with the cell membrane. The substance gets released to outside. This process is therefore commonly known as 'cell vomiting'.


 

Term
enzymes
Definition
organic molecules (usually proteins) that speed up biochemical reactions by lowering the activation energy
Term
activation energy
Definition
energy required for a chemical reaction to begin
Term
active site
Definition
the part of an enzyme to which substrates bind
Term
negitive feedback
Definition
a reaction product temporarily shuts down its own sythesis whenever its levels rise.Negitive feedback may occur by cometive or noncompetive inhibition
Term
competive and noncompetitive inhibition
Definition

competive: change in an enzyme's activity occuring when an inhibitor binds to the active site,competing with the enzyme's normal substrate.

noncompetive:change in an enzyme's shape occuring when an inhibitor binds to a site other than the active site

Term
selective permeability
Definition
membranes have the ability to admit only some substances
Supporting users have an ad free experience!