Which of the following is correct?
a. All living things are composed of multiple cells.
b. All cells arise from existing cells.
c. Organelles are the basic unit of life.
d. Living organisms do not have to be composed of cells.
b. All cells arise from existing cells.
You might also like to view...
A recombinant vaccine is used to protect against
A. polio. B. diphtheria. C. hepatitis B. D. pertussis.
In a segment of DNA, an A base is changed to a C and the error is copied during replication. Under which circumstances is that change considered a mutation? (Select all that apply.)
A) The change alters the phenotype of the organism's offspring. B) The change results in production of a novel protein. C) The change is in a somatic cell, such as a skin cell. D) The change is in a gene, but has no effect on a gene product or phenotype.
Enzymes that are always present, regardless of the amount of substrate, are ________.
A. regulated enzymes B. endoenzymes C. exoenzymes D. constitutive enzymes E. apoenzymes
The type of fish represented by the most living species on earth today are the
A. bony fishes. B. coelacanths. C. sharks. D. rays and skates.