Biology-Chapter 5(Enzymes, energy, etc) Flashcards
Energy
Capacity to perform work. Moving matter in a direction it couldn’t alone.
Kinetic Energy
Energy actually doing the work.
Heat
energy of the movement of molecules in a body of matter. Kind of Kinetic Energy.
Potential Energy
Stored Energy
Chemical energy
potential energy of molecules in the bonds
Thermodynamics
Study of transformations in a collection of matter.
First law of thermodynamics
Energy can be transferred and transformed but never created or destroyed. “Quantity”
Second Law of thermodynamics
energy changes increase entropy/disorder. Lost usable energy->heat created but not valuable. “Quality”
Endergonic Reaction
Requires a net input of energy(absorbs energy from surrounding). Starts with less energy and ends with more energy. Produced by dehydration synthesis. Ex. Photosynthesis.
Exergonic Reaction
Releases energy, starts w/ more energy than ends with. Broken by hydrolysis.
Cellular Respiration
Energy-releasing chemical breakdown of glucose molecules and the storage of energy in a form that the cell can use to perform work.
Cellular Metabolism
Sum of endergonic and exergonic reactions(all energy).
Energy Coupling
Energy released from exergonic reactions to drive essential endergonic reactions. Crucial ability of all cells, atp used.
3 Parts of ATP and bonds
Adenine (nitrogenous base), ribose, chain of three phosphate groups. Bonds between Phosphate groups are unstable covalent, can be broken by hydrolysis.
What happens when the tap bond breaks? What type of reaction?
Phosphate removed, ATP becomes ADP, Energy released. Exergonic Reaction.
Phosphorylation
Transfer of a phosphate group to a molecule. energizing other molecules.
Energy of Activation
Amount of energy that reactants must absorb to start a chemical reaction.
Enzyme, what does it lower?
protein molecule that increases the rate of reaction w/o itself being changed. Speeds it up by lowing the Energy of Activation barrier. Biological Catalyst
Substrate
The substance the enzyme acts on.
Active Site
Small part of enzyme molecule attached to the substrate. Where reaction takes place
ATP is used for what 3 types of cellular work?
Chemical: making of molecules(protein synthesis)
Mechanical: geared towards movement (Muscle Contracting)
Transport: Movement of substances across a membrane (against concentration gradient)
Cofactors
non-protein helpers that help enzymes work
Coenzymes
if the cofactor is an organic molecule
Competitive inhibitor
resembles enzyme’s normal substrate and competes with the substrate for the active site.
Noncompetitive Inhibitor
Binds to enzyme outside of active site and changes shape of enzyme so the substrate can’t fit in active site. Can be reversible or irreversible.
Negative Feedback
When a metabolic reaction is blocked by its products. End product builds up and shuts down process.
Selective permeability
allows some substances to get through easier than others. Allows non-polar, small things, hydrophobic.
What does the phospholipid bilayer let through?
Nonpolar, Hydrophobic, small molecules.
Why is the membrane commonly described as a fluid mosaic?
Mosaic: all different parts of bilayer
Fluid: flexible moving
Glycoprotein
Carbohydrate attached to a protein on the phospholipid bilayer
Glycolipid
Carbohydrate attached to phospholipid bilayer
Diffusion
Tendency for particles of any kind to spread out spontaneously to regions where they are less concentrated.
Passive Transport
Diffusion of a substance across a biological membrane until equilibrium is reached.
Concentration Gradient
Molecule diffused down this until equilibrium is reached. High concentration to low.
Osmosis
Diffusion of water molecules across a selectively permeable membrane.
Hypertonic
Solution with higher concentration of solutes/ low of water.
Hypotonic
Solution with lower concentration of solutes/higher of water.
Water moves from??
Hypo to Hyper, low to high substrate conc, high to low water concentration
Isotonic
Solutions of equal solute concentration
what do animals prefer? what do plants prefer?
P: Hypotonic
A: Isotonic
Osmoregulation
Control of water balance ex. kidney
Facilitated Diffusion
When one protein makes it possible for a substance to move down its concentration gradient.
Active Transport
Requires a cell to expend energy to move molecules across a membrane. Uses transport protein.
Exocytosis
Exports bulky materials using vessicles.
Endocytosis
A cell that takes in macromolecules or other particles by forming vessicles.
Phagocytosis
Cellular eating
Pinocytosis
Cellular drinking
Receptor mediated endocytosis
Opens pit with receptor proteins that pick up molecules from surroundings, the pit will pinch closed to form a vessicle and carry to cytoplasm
Hypercholesterolemia
Characterized by excessively high level of cholesterol in the blood
