________ are the fundamental units that make up all living things.
cells
The size of a metabolizing cell is limited by its
surface area-to-volume ratio.
Whose work proved conclusively that spontaneous generation of life from nonlife was not possible?
Louis Pasteur
The reason that metabolizing cells are small in size is because
the surface area of a cell must be able to accomplish nutrient/waste exchange.
In developing embryos such as a chick, what restores the amount of surface area needed for exchange requirements?
cell division
If a cell has a volume of 3nm, what are the surface area and the volume of the cell?
54nm2, 27nm3
What is the name of a photograph of a specimen obtained with a microscope?
micrograph
Viruses are not made up of cells. According to cell theory, this means what?
Viruses are not living.
Brett needs to distinguish two points that are 0.5 mm apart. What is the easiest way to do this?
Use his eyes.
The light microscope has a resolving power of
0.0001 mm.
What type of microscopy provides a three-dimensional view of the surface of an object?
scanning electron microscope
Angela would like to look at living algae from pond water. What type of microscope should she use?
compound light microscope
Biologists classify cells into two broad categories--animals and plants.
false
Which of the following structures are present in both eukaryotes and prokaryotes?
plasma membrane
Because bacteria are prokaryotes, they do not have DNA.
false
The phospholipid bilayer that surrounds/maintains the integrity of a cell is called a
plasma membrane.
What is the name of the semifluid medium inside the cell?
cytoplasm
The cytoplasm is not considered a cellular organelle.
true
The plasma membrane contains how many layers of phospholipids?
two
Paleontologists have discovered ancient prokaryotic fossils dated at over 3.5 billion years old. These fossils resemble prokaryotes that are capable of living in extreme conditions such as high temperature and salinity. What domain do these prokaryotes belong to?
Archaea
All of the following are possible origins of cell organelles in eukaryotes EXCEPT
groups of prokaryotic cells begin to live in a small group sharing products of metabolism.
Archaea are considered the evolutionary precursors to eukaryotic cells.
true
In the fluid-mosaic model of the plasma membrane, the phospholipid molecules are oriented so that the _____________ heads are facing the outside environment and the ________________ tails are facing the interior of the membrane.
hydrophilic, hydrophobic
Which of the following is not a function of the plasma membrane?
contains the genetic information
Which model currently describes the structure of the plasma membrane?
fluid-mosaic model
A short chain of sugar attached to a protein molecule on the plasma membrane is called
a glycoprotein.
Which of the following can cross the plasma membrane because of its selective permeability?
gases such as oxygen and carbon dioxide
The diffusion of water across a semi-permeable membrane is called
osmosis
During a hurricane, salt water invades fresh water marshes causing many of the plants to die. The plants are killed because the salt water solution is __________________ to the plants, drawing water from their cells.
hypertonic
What is the function of cholesterol in the plasma membrane?
support
A solution is at equilibrium across a plasma membrane. If 50 molecules enter the cell, how many molecules exit the cell?
50
Often when a person is admitted to the hospital, an intravenous solution of normal saline is begun. Since this does not harm the patient, what is the tonicity of normal saline compared to your blood?
isotonic
A certain substance continues to enter the cell in the presence of a metabolic poison that disables the generation of energy by the cell. Where is the higher concentration of the substance?
outside the cell
Choose the CORRECT statement about solute concentrations or particles inside and outside the cell.
In an isotonic solution the amount of water inside and outside the cell is equal.
Brad placed a drop of blood in some distilled water. What happened in the red blood cells?
The cells burst.
The assisted transport of a molecule across the cell membrane without an expenditure of energy is known as what?
facilitated transport
In the sodium potassium pump, sodium and potassium are both pumped out of the cell via active transport.
false
Which of the following does not utilize active transport?
movement of oxygen from the lungs into the blood
Sheree observed an amoeba feeding by engulfing the prey with it's false feet or pseudopods. This process is known as
phagocytosis
During exocytosis, the phospholipids present in the vesicle membrane will end up in the plasma membrane.
true
Which of the following processes moves large molecules across a membrane in the opposite direction of the others?
exocytosis
What cell structure is composed of a stack of slightly curved saccules that are important in packaging and secretion?
Golgi apparatus
What is the obvious dark-stained structure within the nucleus that contains ribosomal RNA called?
nucleolus
The grainy-looking substance inside the nucleus is composed of
DNA and proteins.
The nucleus of a cell in your thigh muscle contains the same genes as the nucleus of a cell in your brain.
true
How large is a nuclear pore in the nuclear envelope?
larger than a ribosome
If a cell lacked ribosomes, it would not be able to
synthesize proteins.
What do the SER and RER have in common?
the formation of transport vesicles
Which of the following would be a way of finishing this hypothesis about the function of the Golgi apparatus? If the Golgi apparatus is involved in packaging products for secretion, then
vesicles must travel from the Golgi to the cell surface.
Which organelle can be likened to a post office?
Golgi apparatus
What cellular organelle is especially abundant in phagocytic white blood cells?
lysosomes
Which of the following is not associated with the cytoskeleton?
microbodies
Centrosomes are associated with
microtubules.
Which of the following is not a function of the cytoskeleton?
process proteins
A microtubule poison would interfere with mitosis and meiosis.
true
Which of the following diseases would you expect in someone with malfunctioning cilia?
recurrent respiratory infections
Why type of junction must there be between the cells of your bladder?
tight junctions
Cilia are composed of microtubules while flagella are composed of actin filaments.
false
In an experiment in the laboratory, a small colored molecule is injected into one cells. Within minutes, the molecule has entered the adjacent cells. What type of junction connects these cells?
gap junctions
What are the folds in mitochondrial membranes called?
cristae
The gel-like fluid substance within a mitochondrion is called the
matrix.
The sum of all of the chemical reactions that occur in a cell collectively are called
metabolism.
In a metabolic pathway, substrate Z is broken down to form product Y and X. Y is further broken down into products V and W. How many enzymes are required for this metabolic pathway?
two
Why is glycolysis believed to have evolved early in the history of life?
It is present in most every type of cell.
Which of the following processes in the breakdown of glucose does not require oxygen?
glycolysis
Only glucose can be used as an energy source in the human body.
false
The first day of football practice was rough on the squad. The players complained of cramps and sore muscles. The reason for their complaints was that there was a __________________ build up in their muscles.
lactate
Since all organisms carry on cellular respiration, all living cells must contain mitochondria.
false
If the mitochondrion is the result of endosymbiosis, what membrane of the mitochondrion represents the engulfing vesicle?
the outer mitochondrial membrane
Fermentation produces more ATP than does aerobic respiration.
false
When ATP is broken down, heat is released.
true
If you could remove all the phosphate in the cell, what would happen to the ATP cycle?
It would stop when all the ATP had been converted into ADP.