BIO 101-501 Test 1
________ occurs when a white blood cell engulfs a bacterium.
Phagocytosis
occurs when a white blood cell engulfs a bacterium.
Phagocytosis
Which of these molecules spontaneously form membranes when mixed in water and most likely were one of the first organic compounds formed on Earth?
Phospholipids
________ are the major lipids of plasma membranes.
Phospholipids
6.You find a cell of a type you have never seen before.The cell has both a nucleus and a cell wall. Therefore,you conclude that it is likely to be a(n) ________ cell.
Plant
A boulder at the top of a hill contains ________ energy
Potential
Which process could result in the net movement of a substance into a cell, if the substance is more concentrated in the cell than in the surroundings?
active transport
10. All of the following options (except one. are locations where ribosomes are found inside the cell. Choose the exception.
inside the nucleus
Where does protein synthesis take place?
on ribosomes
What compound directly provides e in cells by transferring a(n. ________ to those molecules.
phosphate group
9.The concept of a membrane as a fluid mosaic reflects the ability of ________.
phospholipids and most proteins to drift about in the plane of the membrane
What is a gene?
portion of DNA that contains information to produce a protein.
Diffusion ________.
proceeds until a dynamic equilibrium is reached
Which is a feature of prokaryotic cells but NOT eukaryotic cells?
Fimbriae
Most human cells contain ________ chromosomes.
46
Which environments would be best for the functioning of animal and plant cells?
A hypotonic environment for plant cells and an isotonic environment for animal cells.
What compound directly provides energy for cellular work?
ATP
Which statement about an enzyme is TRUE?
An enzyme's function depends on its three-dimensional shape.
In a hypotonic solution, a plant cell will ________.
Become turgid
In eukaryotic cells, what name is given to the region that surrounds organelles but is not found inside the nucleus?
Cytoplasm
Enzymes increase the rate of a reaction by ________.
Decreasing activation energy
When a person cries, tears are exported from cells. Which category of transport most precisely matches this process?
Exocytosis
Directed evolution is a relatively new way to engineer enzymes. Previously, scientists tried to design proteins by using computer models to try to predict how specific changes in genetic sequences might result in altered enzyme structure and function. Why is one of these approaches more efficient than the other?
Generating high numbers of random mutations and subsequently screening for desired function means that directed evolution requires little prior knowledge of enzyme structure.
The endomembrane system includes ________.
Golgi apparatus, lysosomes, vacuoles, and the endoplasmic reticulum
You are riding on your bike and stop pedaling, coasting along the road. Eventually, your bike slows down and stops. What happened to the energy of your motion when your bike stopped?
It was released as heat.
Based on its function in detoxifying drugs one would expect to find a large amount of smooth endoplasmic reticulum in ________ cells.
Liver
When using a microscope to view cells you obtained from scraping under your fingernails, you notice that the cells lack nuclei; therefore, you conclude that the cells must be a type of ________ cell
Prokaryotic
A balloon contains a 10% glucose solution. The balloon is permeable to water but not to glucose. A beaker contains a 5% glucose solution. What will happen when the balloon is submerged in the beaker?
The volume of water in the beaker will decrease.
A hormone that is secreted from a cell is manufactured by ribosomes
___ attached to the rough endoplasmic reticulum _____.
When two solutions that differ in solute concentration are placed on either side of a selectively permeable membrane, and osmosis is allowed to take place, the water will
___ exhibit a net movement to the side with lower water concentration _____.
Some protozoans have special organelles called contractile vacuoles that continually eliminate excess water from the cell. The presence of these organelles tells you that the environment
___ is hypotonic to the protozoan
Diffusion is an example of
___ passive transport _____.
The concept of a membrane as a fluid mosaic reflects the ability of
___ phospholipids and most proteins to drift about in the plane of the membrane _____.
When mixed with water, phospholipids spontaneously form membranes because they
____ have hydrophilic phosphate groups that are attracted to water and hydrophobic fatty acid tails that avoid water
An enzyme's function is most dependent on its
____shape____.
The structural combination of DNA and protein forms
___chromatin_____
You find a cell of a type you have never seen before.The cell has both a nucleus and a cell wall. Therefore,you conclude that it is likely to be a(n)
___plant_____ cell.
7. The nuclear envelope is composed of ________
a double membrane
Which is a feature of prokaryotic cells but NOT eukaryotic cells? The nuclear envelope is composed of
a double membrane
The region of an enzyme to which a substrate binds is called the site.
active
The region of an enzyme to which a substrate binds is called the ________ site.
active site
Active transport ________.
can involve the transport of ions
The principle that energy cannot be created or destroyed is known as ________.
conservation of energy
8. In eukaryotic cells, what name is given to the region that surrounds organelles but is not found inside the nucleus?
cytoplasm
In eukaryotic cells, what name is given to the region that surrounds organelles but is not found inside the nucleus?
cytoplasm
What molecules are scientists currently trying to use to generate power for nanotechnology devices, such as microscopic robots?
enzymes
Specialized cells that line the stomach synthesize a digestive enzyme and secrete it into the stomach. Which process could be responsible for its secretion?
exocytosis
Some protozoans have special organelles called contractile vacuoles that continually eliminate excess water from the cell. The presence of these organelles tells you that the environment ________.
is hypotonic to the protozoan
An object at rest has no ________ energy, but it may have ________ energy resulting from its location or structure.
kinetic; potential
Information is transferred from the nucleus to ribosomes via ________.
mRNA
The extracellular matrix of animal cells ________.
protects and supports cells
Which is a function of the Golgi apparatus?
protein modification
Usually, enzymes are ________.
proteins
Which is a function of the plasma membrane?
regulate traffic of chemicals in and out of the cell
If placed in tap water, an animal cell will undergo lysis, whereas a plant cell will not. What accounts for this difference?
relative inelasticity and strength of the plant cell wall
Anything that prevents ATP formation will most likely ________.
result in cell death
The combination of sucrose, sucrase, and water produces sucrase, glucose, and fructose. Which component of the reaction is the enzyme?
sucrase (always ends in ase.)
Energy can be defined as ________.
the capacity to cause change
Osmosis can be defined as ________.
the diffusion of water across a selectively permeable membrane