Chapter 5 review questions
Glucose is taken up by red blood cells by binding to a specific pocket in a membrane protein that then allows it to cross the membrane and move down its concentration gradient. What would be the best explanation of this process.
Facillitated diffusion using a transporter.
Fe +2 = Fe+3
False
NO2- = NO3-
False
What law states that energy cannot be created or destroyed
First law of thermodynamics
A calorie is a commonly used-unit of chemical energy. It is the unit of
Heat
What is the original source of most energy in the biosphere
Solar energy from the suns
In an enzyme- catalyzed reaction, the reactant is called the
Substrate
Facilitated diffusion is an important method for cells in obtaining necessary molecules and removing other ones. Requirements for facilitated diffusion include which of the following
The carrier molecule must be specific to the molecules that is transported. The direction of movement is always with the concentration gradient, never against the gradient.
Why does a human blood cell lyse when placed in a hypotonic solution while a plant cell does not.
The cell wall of the plant prevents the membrane from swelling too much.
Nad+ + e- + H + NADH
True
Pyruvate + 2e- = Lactate
True
a scientist performs an experiment in which they create an artificial cell with a selectively permeable membrane through which only water can pass. They inject a 5 M solution of glucose into the cell and then place the cell into a beaker of water. After an hour, what effect do you expect to observe.
Water moves into the cell
If you were to replace the phosphate group of a phospholipid with a fatty acid chain, you would have
a triglyceride
The energy needed to destabilize existing chemical bonds and start a chemical reaction is called
activation energy
Osmosis occurs as water can cross the lipid bilayer through specialized channels for water movement called
aquaporins
intergral membrane proteins ______ in a membrane
can move laterally
a drug binds to the active site of an enzyme. If it is bound to the active site of the enzyme. it prevents substrate binding. This drug would be considered a
competitive inhibitor
you are studying an enzyme- catalyzed reaction that induces a particular cellular function in the lab. If you wanted to slow down that particular cellular function by controlling the enzyme, what could you do
decrease the temperature of the incubator below the optimal temperature.
The net movement of substances to regions of lower concentration is called
diffusion
when you breathe, oxygen moves from your lungs into your blood and then into tissues. To do this, oxygen moves across membranes by blank and from blank concentration of oxygen
diffusion; higher to lower.
oxidation and reduction reactions are chemical processes that result in a gain or loss of
electrons
Membrane proteins are not very soluble in water because they possess long stretches of non polar amino acids that are
hydrophobic
if two solutions have unequal concentration of a solute, the solution with the lower concentration is called
hypotonic
the chemistry of living systems representing all chemical reactions is called
metabolism
the process often referred to as "cellular eating is
phagocytosis
in membranes _______ associate to form two layers
phospholipids
the lipid layer that forms the foundation of cell membranes is primarily composed of molecules called
phospholipids.
larger ________ float within the bilayer
proteins
the plasma membrane is a thin sheet of lipid embedded with
proteins
RNA molecules that act as enzymes are given the name
ribosomes
Energy Is defined as
the capacity to do work
How are the tails and heads of membrane phospholipids oriented in their environment
the hydrophobic tails are oriented toward each other and the hydrophilic heads are oriented towards the extracellular fluid and the intracellular fluid.
In a single sodium, potassium pump cycle, ATP is used with the result that
three sodium ions leave and two potassium ions enter
