Biology - Chapter Five
In a coupled reaction, released from the energy-releasing reaction is used to drive an reaction
1. Energy 2. Energy-requiring
During muscle contraction, ATP binds to filaments, which change shape following ATP breakdown and bind to filaments
1. Myosin or thick 2. Actin or thin
Features of Metabolic Pathways
1. Pathways are organized 2. Chemical reactions are linked to each other 3. One reaction leads to the next reaction
Features of an enzyme
1. Speeds up a reaction 2. Protein based molecule
After an enzyme-catalyzed reaction has been completed, the product(s) is/are released and the ________ site of the enzyme returns to its original shape, ready to bind another______ molecule.
1. active 2. substrate
Energy flows between chloroplasts and mitochondria as they carry out chemical reactions; the _________ of the cellular respiration, carbon dioxide and water, are the ____________ for photosynthesis, and vice versa
1. products 2. reactants or substrates
A solution is composed of a ________ dissolved in a ___________
1. solute 2. solvent
In order for ATP to be stable there needs to be __________ phosphate groups.
2 or two
Which of the following statements explain the name of the "induced fit model" 1. The Induced fit model described how the substrate is induced to undergo a slight alteration to achieve optimum fit with its enzyme 2. The induced fit model describes how the enzymes is induced to undego a slight alteration to achieve optimum fit with its substrate.
2. The induced fit model describes how the enzymes is induced to undergo a slight alteration to achieve optimum fit with its substrate
A cell contains a 4% concentration of salt. The cell's environment is isotonic. Which is a possible salt concentration outside the cell
4%
A cell with a 0.5% concentration of salt inside it is placed into a solution. The cell begins to shrink. What is a possible concentration of salt outside the cell?
5.0%
When ATP is used as a energy source, a phosphate group is removed by hydrolysis. How is ATP regenerated during the ATP cycle?
ATP is regenerated in mitochondria during cellular respiration
When ATP is used as an energy source, a phosphate group is removed by hydrolysis. How is ATP regenerated during the ATP cycle?
ATP is regenerated in mitochondria during cellular respiration
The portion of an enzyme that accommodates the substrate(s) is termed the _____________ _______________
Active Site
Aquaporins are categorized as which type of proteins
Channel Proteins
In what type of reaction is the energy released from one reaction used to drive a second, energy-required reaction
Coupled reaction
Define osmosis
Diffusion of water through a selectively permeable membrane
The process by which substances are moved into a cell by vesicle formation is called
Endocytosis
What process do cells use to engulf larger substances, encase them in vesicles, and bring them into the cell?
Endocytosis
Plants wilt because their cell membranes are no longer pushing against their cell walls. What process have such plant cells undergone?
Plasmolysis
Which cellular process occurs in chlorplasts
Photosynthesis
Mitochondria utilize chemical energy and oxygen produced during
Photosynthesis to carry out cellular respiration
What is the term that means that a cell membrane has pulled away from a cell wall due to water loss?
Plasmolysis
If a cell is placed in a hypotonic solution, what will occur?
Water will enter the cell from the solution
The amount of energy for activation needed for an reaction is decreased when a(n) _____________ is present
catalyst or enzyme
In a chemical reaction, an enzyme speeds up the rate of the reaction by _____ the energy of an activation needed for the reaction to occur.
decreasing
The movement of molecules from an area of higher concentration to an area of lower concentration without energy or carrier proteins is called simple _______________
diffusion
Active Transport requires __________ to move molecules
energy or ATP
bulk transport
energy used to move large substances
In a hypotonic solution the concentration of water inside the cell is ________ than the concentration of water in the surrounding solution
less
In a hypotonic solution the concentration of water inside the cell is __________ than the concentration of water in the surrounding solution
less
The energy of activation
limits how fast a reaction can proceed
Within a solution, the solvent is the _______________ portion
liquid
Molecules that undergo exocytosis from a cell are enclosed in _____________
vesicles
Why does active transport require energy?
- Molecules are moved against the concentration gradient
The correct differences between receptor-mediated endocytosis and pinocytosis
- Unlike pinocytosis, receptor-mediated endocytosis allows cells to take in a specific molecule - Unlike pinocytosis, receptor-mediated endocytosis requires a specific receptor protein to recognize a specific molecule
The sodium-potassium pump involves active transport in which type of animal cells
- nerve - muscle cells
Identify the cells that would use pinocytosis to ingest substance
- white blood cells - plant root cells
A cell a 0.5% concentration of salt inside it is placed into a solution. The cell begins to swell. What is a possible concentration of salt outside the cell?
0.1%
How many substrates can an enzyme fit into
1
Which of the following are ways in which ATP hydrolysis is coupled to an energy-required reaction
1. ATP is using to change the shape of a reactant 2. ATP is used to energize reactant
Which three of the following are advantages of using ATP as a energy carrier in living systems
1. ATP releases energy quickly, which facilitates the speed of enzymatic reactions. 2. When ATP becomes ADP+P, the amount of energy released is usually just enough for a biological purpose. Breaking down an entire carbohydrate or fat molecule would be wasteful, because it would release much more energy than is needed. 3. The structure of ATP allows its breakdown to be easily coupled to an energy-requiring reaction as described next.
A series of linked chemical reactions that produce an end product is
A Metabolic Pathway
Which of the following might be a target of phagocytosis
A cell
The energy currency of the cell is
ATP
Which of the following is a channel protein through which water can diffuse across a membrane
Aquaporin
Ideally, which molecules are broken down during cellular respiration in the mitochondria
Carbohydrates
The breakdown of fats and provides the majority of energy for ATP synthesis in a cell.
Carbohydrates
During muscle contraction ATP provides the for the contraction
Energy
What is the term used when an active enzyme is prohibited from joining with its substrate, thus preventing the progress of a reaction
Enzyme inhibition
What type of transport across cell membranes involves the use of carrier proteins
Facilitated diffusion
True or False: During enzyme inhibition, the unused portion of the enzyme is degraded or recycled
False
What kind of solution contains a comparatively higher concentration of solute than can be found inside a cell
Hypertonic solution
To maintain turgor pressure, plant cells must exist in a slightly ______ environment.
Hypotonic
Which of the following describes how the structure of ATP makes it a good energy source for cells
It can be easily broken down and coupled to energy-requiring reactions,
The following diagram shows the ATP cycle. What happens to the phosphate that is hydrolyzed to provide the energy for cellular work.
It is joined to an ADP molecule using the energy from cellular respiration
Why is it the induced fit of an enzyme important as it binds its substrates
It results in optimum fit between the two
Why is the induced fit of a enzyme important as it binds its substrate
It results in optimum fit between the two
What happens to an enzyme after it has catalyzed a reaction?
It returns to its original shape
Turgor pressure is created by the force of the cell pushing against what?
Its cell wall
Which of the following is true about diffusion
Molecules move down their concentration gradients
Bulk transport must be utilized for which of the following classes of molecules
Molecules that are too large to fit through carrier proteins
Define pinocytosis
Process by which vesicle formation brings a liquid or very small particles into the cell.
An enzyme is a ______ molecule that functions as a organic catalyst to speed a chemical reaction
Protein
During a chemical reaction involving an enzyme, the enzyme specifically acts on the _________
Substrates
Three structural features of Adenosine Triphosphate (ATP).
Sugar ribose, the nitrogen-containing base adenine, and three phosphate groups.
A cell with 0.2% concentration of salt is placed in an isotonic solution. What is the concentration of salt in that solution
The concentration of salt in that solution must be 0.2%.
Which of the following statements explains that name of the "Induced fit model"?
The induced fit model describes how the enzyme is induced to undergo a slight alteration to achieve optimum fit with its substrate
Define facilitated diffusion
The movement of molecules across a membrane using carrier proteins
The sodium-potassium pump acts alternately to move sodium and potassium in and out of animal cells by what means
The pump undergoes a change in shape
Which of the following best explains why a hypertonic solution causes a cell to shrink
Water rushes out of the cell
Why are the phosphates groups unstable within the ATP molecule
The three phosphate groups repel each other
Why is it beneficial to a cell for feedback inhibition to regulate the activity of an enzyme in a reaction
This ensures that the enzyme is only active when levels of the product of the reaction are low
Why is it eneficial to a cell for feedback inhibition to regulate the activity of an enzyme in a reaction
This ensures that the enzyme is only active when levels of the product of the reaction are low
What makes a portion of the ATP molecule makes its unstable
Three Phosphate Groups
True or False: ATP stores more potential energy than ADP
True
True or False: Receptor-mediated endocytosis requires a specific receptor protein to recognize a specific molecule
True
Aquaporins allow which type of molecule to travel more rapidly through the membrane?
Water Molecule
Enzyme inhibition occurs when
a molecule binds to the enzyme that prevents the substrate from binding.
The energy that must be supplied in order to cause molecules to react with one another is called the energy of
activation
Which of the following bases are found in ATP
adenine
Enzymes will
alter the rate of a reaction
The activity of most enzymes and metabolic pathways is regulated by ________
feedback inhibition
Which of the following is the preferred source of energy of the production of ATP in a cell?
glucose
If a cell is surrounded by a hypertonic solution, the solution has a ___________ solute concentration than the cell's cytoplasm
higher
During osmosis, water moves from a region of ___________ concentration of water, to one of _______________ concentration of water
higher to lower
Which type of substances are moving across the membrane during facilitated diffusion
ions
When the concentration inside a cell is the same as outside, the cell is said to be in an ___________ solution
isotonic
The process of cellular respiration in organelles is called
mitochondria
A cell placed in hypotonic solution has solute that are _________ concentrated inside the cell than in the solution outside the cell.
more
active transport
movement against a concentration gradient
passive transport
movement from high to low concentration
When we measure diffusion, we are actually measuring _____________
net molecular movement
The plasma membrane only allows some substances to cross, which means it is selectively
permeable
The process by which a cell takes in larger particles by means of vesicle formation is called
phagocytosis
The process by which cells can take in liquid or small particles in called
pinocytosis
The process by which cells can take in liquids or small particles is called
pinocytosis
What function does ATP have in a cell
provides readily accessible energy
Proteins in the cell membrane involved in active transport of sodium and potassium across the membrane are also called ______
pumps
ATP is coupled to an energy-requiring reaction when ATP is used to energize, or change the of a reactant.
shape
Chloroplast capture energy
solar
The plasma membrane is selectively permeable, allowing ____________ substances to cross
some