Exam 2
Membrane proteins are not very soluble in water, because they possess long stretches of non-polar amino acids that are
hydrophobic
The cytoplasmic space in eukaryotic cells is occupied by many diverse membrane-bound structures each with specific cellular functions called
organelles
On the outer surface of the plasma membrane there are Marker molecules that identify the soul type often these molecules are
Carbohydrates chains attached to either a protein or phospholipid
In a single sodium-potassium pump cycle, ATP is used with the result that
3 sodium ions leave and 2 potassium ions enter
Incubation of cells at 20C blocks the release of packaged proteins from the Golgi. Under such conditions you would expect to see
A decrease in exocytosis
A type of transport of solute across a membrane, up its concentration gradient, Using proteins carriers driven by the expenditure of chemical energy is known as
Active transport
Membrane proteins serve many functions. One of the functions is transportation of substances across the membrane. If a cell biologist places cells into an environment in which a chemical has been added that blocks the function of these proteins, the process that will be affected is
Active transport
Schleiden and Schwann stated the cell theory which in its modern form says
All organisms are composed of one or more cells also as are the smallest living things and all souls arise by division of other cells
Metabolic reactions fall under two general categories: anabolic and catabolic. What type of chemical reactions are these two classes of metabolic reactions?
Anabolic reactions are endergonic reactions, whereas catabolic reactions are exergonic.
Centrioles are found in
Animal cells and most protists
Microfliaments such as actin, microtubles, and the intermediate filaments form the cell supporting structure called the
Cytoskeleton
mitochondria and chloroplasts are the organelles besides the nucleus that contain
DNA
Small cell functions more effectively, because as cells become larger the surface area to volume ratio
Decreases
What is the net movement of substances to regions of lower concentration card
Diffusion
Passive processes ______ while active processes _______?
Do not require energy, require energy
oxidation and reduction reaction are Chemical processes that result in a gain or loss of
Electrons
If a cell has the same concentration of dissolved molecules as it's outside environment, the cells condition is referred to as being
Isotonic
The organelle that can collect package modify and transport molecules is called the
Golgi apparatus
the eukaryotic organelle that is directly involved in the transport of proteins
Golgi body
Hypertonic solutions have a _______ solute concentration so they _______ water and the cells __________.
Higher, gain, burst
A research laboratory is attempting to collect the contents of human red blood cells. The type of solution researchers should use to cause blood cell to Lyse (burst) would be
Hypotonic
Streptomycin is an antibiotic that interferes with the function of the 30S subunit of the prokaryotic ribosome. What is the consequence of treating a bacteria with streptomycin?
Impaired protein synthesis
You are working with a specific enzyme-catalyzed reaction in the lab. You are a very careful experimentalist, and as a result, at the beginning of each of your experiments, you measure the temperature in the lab. On days 1 through 5, the temperature in the lab was 20°C. Today is days 6 of your experiment, and the temperature in the lab is 30°C. How do you predict that this will alter the rate of your enzyme-catalyzed reaction
It could possibly increase or decrease the rate depending on what enzyme it is
Glucose is broken down through cellular respiration, which involves a large number of chemical reactions. At the end of the cellular respiration process, A large number of ATP molecules are generated, but yet, not all of the possible energy that is contained in a molecule of glucose can be harnessed through these chemical reactions to generate ATP. In other words during cellular respiration not all of the energy that is contained in a molecule of glucose is converted into the energy stored in ATP. What happened to the remaining energy?
It is lost as heat
Alcohol consumption adversely affects the synthesis of molecules involved in protein degradation (these molecules are found in a particular organelle), which can eventually lead to liver damage. Given this information which organelle in liver cells is most directly affected by alcohol consumption?
Lysosomes
The chemistry of living systems representing all chemical reactions is called
Metabolism
The organelle involved in the oxygen requiring process by which the energy harvested from macromolecules is used to generate ATP, known as the "powerhouse of the cell" is the
Mitochondria
A 20% solute solution and 10% solute solution are separated by a semipermeable membrane which will allow only water to pass through it
Net movement of water will be into the side with 20% solution
You eat a bowl of beans as part of your dinner. As you digest the beans, The proteins that are present get broken down into their component amino acids. As your body destroys the macromolecules that were present in the beans, is the energy present in those molecules destroyed
No. The energy contained within these macromolecules is converted into other forms of chemical energy and kinetic energy, though some is lost as heat.
The price is often referred to as cellular eating is (example when an immune so uptakes a bacteria cell)
Phagocytosis
The lipid layer that forms the foundation of cell membrane is primarily composed of molecules called
Phospholipids
Which of these is the bulk transport system which brings into the cell only fluids with its dissolve substances
Pinocytosis
One difference between plant and animal cells is
Plant cells have chloroplast but animal cells do not
Kinases are enzymes that can phosphorylate (transfer phosphate groups onto) macromolecules such as proteins. A particular kinase, Kinase 1 is known to promote cell division. Kinase 1 promote subdivision by phosphorylating Protein X. Phosphorylation of Protein X activates Protein X. Once activated, Protein X stimulates the production of other proteins such as Protein Y and Z that directly promote cell division. In order to function, Kinase 1 requires the presence of Metal A. However, in the presence of Protein A, Kinase 1 is nonfunctional. From the description, what is considered the substrate of Kinase 1?
Protein X
When an atom or molecule gains one or more electrons, it is said to be
Reduced
Adenosine triphosphate is composed of
Ribose, adenine, and three phosphates
In an enzyme-catalyze reaction, the reactant is called the
Substrate
One of the fundamental and tenets of biology is that _____ is/are the basic unit of life
The cell
The law of thermodynamics that states that energy cannot be created or destroyed is
The first law of thermodynamics
Based on the graph what are the optimal temperatures for the human enzymes and HotSprings prokaryote enzymes
The optimal temperature for a human enzyme is 40°C. The optimal temperature for the Hot Springs prokaryote Enzyme is 72°C.
Many metabolic pathways are ultimately concerned with ATP, Either with the generation of ATP, or with the requirement of ATP for that pathway to function. Why is ATP so important to metabolism?
The phosphate groups of ATP, are held together by unstable bonds that can be broke into release energy
You return home to find that your baby brother has scattered his toy trains And trucks all over the floor of your room. As you begin to pick up the toys and put them away you realize that even though he is just a baby he has clearly mastered
The second law of thermodynamics
The ultimate source of energy for humans and all other life comes from watt source
The sun
A cytologist is examining a tissue under an electron microscope. He notices that the endoplasmic reticulum of each cell is extremely rough in appearance and he knows that the rough appearance is because of many, many ribosomes embedded there. He asks why there are so many ribosomes. You respond
This tissue exports proteins to other areas of the body
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 5M solution of glucose into the soul and then place the soul into a beaker of water. after an hour what a fax do you expect to observe
Water moves into the cell
Plants fungi and bacteria all have
cell walls
Plant cells often have a large membrane-bound sac that is used for storing water and other substances called a:
central vacuole
In an experiment described in a chemistry lab book, the directions state that after mixing two chemicals (A and B) and waiting 5 minutes that will be oxidized. This means that
chemical A has lost electrons to chemical B.
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
The synthesis of sugar molecules through the process of photosynthesis requires energy absorbed from sunlight. Bearing this in mind what kind of reaction is photosynthesis
endergonic
In eukaryotes mitochondria are the organelles primarily involved in
energy release/capture
carrier mediated transport is also called
facilitated diffusion
The amount of energy available to do work is called
free energy
Prokaryotic cells
lack membrane bound nucleus
Cholesterol functions in the plasma membrane to
maintain fluidity
The cilia and flagella of eukaryotic cells are composed of
microtubules in a 9 + 2 arrangement
For the process of diffusion to occur, molecules must
move from areas of high concentration to areas of lesser concentration until an equilibrium is reached.
Organelles that break down hydrogen peroxide into water and oxygen are
peroxisomes
Energy is defined as
the capacity to do work
In order to reuse an enzyme after the conclusion of an enzyme catalyzed reaction, what must occur
the enzyme has to separate itself from the product
