Chapter 4 Enzymes Flashcards
(34 cards)
What is the net movement of water across a selectively permeable membrane is into the?
Hypertonic solution
What allows the cell to move substances into the cell without moving it through the plasma membrane?
Both phagocytosis and pinocytosis.
What is energy?
Energy is the ability to do work.
Compare potential and kinetic energy.
Potential energy is stored energy available to do work.
Kinetic energy is energy being used to do work.
Explain the first and second law of thermodynamics?
First law states that energy cannot be created or destroyed, energy can be converted to others form.
Second law states that all energy transformations are inefficient because every reaction loses some energy to the surroundings as heat.
What is thermodynamics?
It is the study of energy transformation.
What is metabolism?
The break down of existing molecules to build new structure and repair old ones.
Compare endergonic and exergonic reactions.
Endergonic requires an input of energy to proceed.
Exergonic releases energy.
How do cells avoid chemical equilibrium.
They do this by preventing the accumulation of products
Explain oxidation-reduction reactions.
It transfer energized electrons from one molecule to another.
What is electron transport chain?
Each protein accepts an electron from the molecule before it passes it to the next.
How are electron transport chain used during photosynthesis and respiration?
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What is ATP?
It temporarily store much of the released energy.
How does ATP temporarily store small amounts of cellular energy?
ATP holds energy released in exergonic reaction. ATP is a type of nucleotide the phosphate groups place three negative charges very close to one another. This arrangement makes the molecules unstable so it releases energy.
What is a coupled reaction?
Are simultaneous reactions in which one provides the energy that drives the other.
What is phosphorylation?
Transferring its phosphate group to another.
What is an enzyme?
It is an organic molecule that catalyzes a chemical reaction without being consumed.
How are they match makers?
An enzyme’s active site has a specific shape that binds to one or more substrates. After the reaction is complete, the enzyme releases the product.
What is osmosis?
Is the simple diffusion of water across a selectively permeable membrane.
What is concentration gradient?
A solute is more concentrated in one region than in a neighboring region.
What is isotonic?
Solute concentration is the same as the inside of the cell.
What is hypotonic?
The solute concentration is lower than it is inside the cell.
What is hypertonic?
Surroundings have a higher concentration of solutes than the cell’s cytoplasm.
Compare methods by which materials enter and leave the cell.
Passive transport is when a substance moves across a membrane without the direct expenditure of energy.
Osmosis is two solutions of different concentrations may be separated by a selectively permeable membrane through which water, but not solutes can pass.
Active transport is transport protein moves substances against its concentration gradient requires energy.
Endocytosis is membrane engulfs a substance and draws it into the cell.
Executors is vesicles fuses with cell membrane, releasing substances outside of the cell.
Facilitated diffusion is substances to which the membrane is not permeable move across the membrane with the assistance of transport proteins.
Exocytosis vesicles fuses with cell membrane, releasing substances outside of the cell.
