Untitled Flashcards Set

Enzymes speed up chemical reactions by lowering the activation energy, which allows the reaction to proceed much more quickly.

Lactose takes years to break down on its own. But if exposed to the protein lactase, the reaction proceeds very quickly, while lactase itself remains unchanged. Lactase is an example of a(n) enzyme.

An enzyme is considered a(n) catalyst because it speeds up a chemical reaction without being used up.

During an enzymatic reaction, a molecule of substrate binds to the enzyme and is broken down into one or more molecules of product, which are released.

A(n) inhibitor is a molecule that can bind to an enzyme and prevent the enzyme from working.

High temperatures or changes in pH can denature an enzyme, causing it to lose its shape and biological activity.

The specific location within an enzyme molecule where the substrate binds is called the active site.

The induced fit between an active site and its substrate often strains bonds and helps the reaction proceed.

The region of an enzyme called the active site has the shape and chemistry that fits one specific substrate molecule. Relationship of structure to function

There is more oxygen gas in the air of our lungs than in the blood. Therefore, oxygen moves by passive transport from the air into the bloodstream. Interactions within biological systems

Because all cells have a plasma membrane, it is logical to infer that membranes first developed in the earliest forms of life on Earth. Evolution

ATP energizes other molecules in cells by transferring phosphate groups to those molecules. Pathways that transport energy and matter

What is the best definition of energy? The capacity to cause change

What is true about energy? It cannot be created or destroyed

What is an example of potential energy? A bowling ball placed on the top shelf of a closet

How are combustion and cellular respiration different? Cellular respiration breaks down sugar where combustion breaks down octane

What is the function of ATP? It provides energy for cellular work

Orange, 56 minutes, 1 pound, jumping rope, 1 cheeseburger 2 oranges 3 slices of pepperoni pizza

A space station orbiting earth is exhibiting what type of energy? Kinetic

“Conservation of energy” refers to the fact that ____. Energy cannot be created or destroyed but can be converted from one form to another

Chemical energy is a form of ____ energy. Potential

In your body, what process converts the chemical energy found in glucose into the chemical energy found in ATP? Cellular respiration

What are the by-products of cellular respiration? Water and

Cells use what molecule to store the chemical energy released by the breakdown of food molecules during cellular respiration? ATP

What are the components of the molecule ATP? An organic molecule called adenosine and three phosphate groups

ATP drives work in cells by ____. Transferring its phosphate group to other cell molecules.

Most enzymes are ____. Proteins

Enzymes work by ____. Reducing activation energy in a reaction

An enzyme is a(n) ____. Organic catalyst

What name is given to the reactants in an enzymatically catalyzed reaction? Substrate

As a result of its involvement in a reaction, an enzyme ____. Remains unchanged

An enzyme is a molecule that ____.  Changes the rate of a metabolic reaction without being consumed by the reaction

Activation energy can be described as ____. Energy that must be invested to start a reaction

What best explains the observation that enzymes are selective in the reactions they catalyze? There is a precise compatibility between an enzyme’s active site and the substrate molecule

When molecules move down their concentration gradient, they move from where they are ____ to where they are ____. More concentrated, less concentrated

Diffusion across a biological membrane is called ____. Passive transport

Endocytosis moves materials ____ a cell via ____. Into…membranous vesicles

You can recognize the process of pinocytosis when ____. The cell is engulfing extracellular fluid

A white blood cell engulfing a bacterium is an example of ____. Phagocytosis

Facilitated diffusion is a type of ____. Passive transport

What name is given to the process by which water crosses a selectively permeable membrane? Osmosis

Exocytosis involves the movement of molecules from ____ the cell to ____ the cell. Inside, outside

Endocytosis involves the movement of molecules from ____ the cell to ____ the cell. Outside, inside

A vesicle inside the cell fuses with the plasma membrane and releases its contents outside the cell. Exocytosis

____ is a form of passive transport in which molecules move across the plasma membrane using a transport protein. Facilitated diffusion

The plasma membrane forms a pocket that pinches inward, forming a vesicle that contains material from outside the cell. Endocytosis

____ is a form of passive transport in which molecules move across the plasma membrane by crossing a lipid bilayer. (Simple) diffusion

____ requires energy from the cell. Molecules move against their concentration gradient. Active transport

The ideal osmotic environment for an animal cell is a(n) ____ environment. Isotonic

An animal cell placed in a(n) hypotonic solution will ____. Gain water, swell, and possibly burst

There is a net diffusion of water out of an animal cell when it is placed in a(n) ____ solution. Hypertonic

The ideal osmotic environment for a plant cell is a(n) ____ environment. Hypotonic

A plant cell placed in a(n) hypertonic solution will ____. Lose water and plasmolyze

A plant cell surrounded by a(n) isotonic solution will be ____. Flaccid (limp)

The passive movement of molecules from an area of higher concentration to an area of lower concentration is called ____. Diffusion

An animal cell placed in a hypertonic solution will ____ water by ____. Lose…osmosis and shrivel

In osmosis, water moves across a selectively permeable membrane toward the ____ solution; that is, toward the solution with the ____ solute concentration. Hypertonic…greater

The concentration of calcium in a cell is 0.3%. The concentration of calcium in the surrounding fluid is 0.1%. How could the cell obtain more calcium? Through ____ transport. Active

“The use of energy to move molecules across a membrane” is the definition of ____. Active transport

What is sometimes referred to as cell eating? Phagocytosis

What is sometimes referred to as cell drinking? Pinocytosis