About one in one million people are born with Dyskeratosis Congenita. This
disease affects many areas of the body. It causes fingernails and toenails to grow abnormally and discoloration of the skin. Dyskeratosis Congenita is caused by a mutation in a gene responsible for the production of ribosomes; therefore, ribosome functioning is impaired. What is the function of the ribosomes?
a
They produce proteins
b
They remove substances
c
They breakdown chemicals
d
They produce energy
a) They produce proteins
Which of these describes diffusion?
a
The active transport of particles into a cell
b
The active transport of particles out of a cell
c
The net movement of any type of molecule from a region of lower concentration to a region of higher concentration
d
The net movement of any type of molecule from a region of higher concentration to a region of lower concentration
d) The net movement of any type of molecule from a region of higher concentration to a region of lower concentration
Which method of transport moves substances in or out of the cell that REQUIRES ENERGY?
a
diffusion
b
facilitated diffusion
c
osmosis
d
active transport
d) active transport
How do active transport and facilitated diffusion differ?
a
one uses help from proteins and the other does not
b
one requires energy and the other does not
c
active transport moves molecules against a concentration gradient and facilitated diffusion does not
d
both b & c
d) both b & c
Which statement best describes the plasma membrane of a living plant cell?
The plasma membrane of a plant cell is
a
composed of two layers of proteins and carbohydrates only.
b
composed of two layers of proteins with floating molecules of lipids only.
c
designed to allow for the free flow of all protein substances to move into and out of the cell.
d
designed to allow certain substances to enter and certain substances to exit the cell.
d) designed to allow certain substances to enter and certain substances to exit the cell.
Chlamydia is a sexually transmitted disease that is caused by a bacterium called Chlamydia trachomatis.
Which of these are characteristics of the infectious agent that causes chlamydia?
a
Non-living particle that replicates only inside of other organisms
b
Unicellular organism that can only replicate inside of other organisms
c
Unicellular organism that is a prokaryote.
d
Non-living particle that contains DNA or RNA