The smallest living unit within the human body is |
the cell |
The watery component of the cytoplasm is called |
cytosol |
Which of the following terms is not used to define the structure that separates the contents of a human cell from its surrounding medium? |
cell wall |
Functions of the plasmalemma include all of the following, except |
thermal insulation |
The plasma membrane is composed of |
a bilayer of phospholipids |
The plasma membrane is composed of |
a bilayer of phospholipids |
Each of the following is an example of a nonmembrane organelle, except |
lysosomes |
Components of the cytoskeleton may include all of the following, except |
microsomes |
Most of the ATP required to power cellular operations is produced in the |
mitochondria |
Synthesis of lipids and glycogen takes place at the |
smooth ER |
Which of the following consists of a network of intracellular membranes with attached ribosomes? |
rough enodplasmic reticulum |
Renewal or modification of the cell membrane is a function of the |
Golgi apparatus |
Organelles that absorb and neutralize drugs and toxins are |
peroxisomes |
When activated, lysosomes function in |
digestion of foreign material |
Most of a cell's DNA is located in its |
nucleus |
The control center for cellular operations is the |
nucleus |
The complex structures of DNA and protein found in the cell nucleus are |
chromosomes |
The movement of oxygen from an area of high concentration to an area of low concentration is an example of |
diffusion |
Diffusion of a substance across the cell membrane is influenced by all of the following, except |
hydrolysis of ATP |
Water molecules and small ions enter a cell through |
channels formed by integral proteins |
A solution that contains a lower osmotic pressure than the cytoplasm of a cell is called |
hypotonic |
"Spikes" form on a blood cell when it is placed in a(n) ________ solution |
hypertonic |
The process by which molecules such as glucose are moved into cells along their concentration gradient with the help of membrane-bound carrier proteins is called |
facilitated diffusion |
A process that requires cellular energy to move a substance against its concentration gradient is called |
active transport |
The intake of small membrane vesicles from the extracellular fluid is called |
endocytosis |
The principal cations in our body fluids are ______ and _______ |
sodium; potassium |
In order to maintain cellular homeostasis, an example pump ejects ions from the cell and imports ________ ions. |
sodium; potassium |
Many proteins in the cytosol are _______ the accelerate metabolic reactions. |
enzymes |
The skin swells and puckers during a long bath. This suggests that bath water is a(n) _______ fluid. |
hyoptonic |
Red blood cell shrinkage is to ______ as cell bursting is to ______. |
crenation; hemolysis |
A defense cell engulfing a bacterium illustrates |
phagocytosis |
Compared to the extracellular fluid, cytosol contains |
a higher concentration of potassium ions |