The red-cockaded woodpecker is an endangered species living in the southeastern U. S. Two of the primary factors that have contributed to the species' decline in numbers are: 1) Old pine trees required for nesting sites have been clearcut and logged by humans.

2) Humans have suppressed wildfires, which normally clear out other kinds of trees (hardwoods) from the understory. These hardwoods disrupt the woodpeckers' habitat and prevent new pines from growing.

Which of the following would be an important part of a multi-step plan to restore the stability of the red-cockaded woodpecker's ecosystem?
A.
Install irrigation systems to help prevent fires in the understory.
B.
Limit further logging and clearcutting of pine trees.
C.
Encourage planting of understory hardwoods.
D.
Prevent logging of pine trees, but encourage pine clearcutting.

In a hypothetical breed of dogs, coat color is controlled by two genes. there are six different coat colors in this breed: black, brown, cream, gray, silver, and tan. consider the following crosses. cross 1: black females from a lineage of all black dogs are crossed with brown males from a lineage of all brown dogs. f1 males and females are all black. when f1 are intercrossed, f2 males and females are black or brown. cross 2: black females from a lineage of all black dogs are crossed with tan males from a lineage where all males are tan and all females are cream. f1 males are black, f1 females are gray. when f1 are intercrossed, f2 males and females are black, brown, gray, or tan. cross 3: silver females from a lineage where all females are silver and all males are gray are crossed with brown males from a lineage of all brown dogs. f1 males and females are all gray. when f1 are intercrossed, f2 males are black, brown, gray, or tan, f2 females are cream, gray, silver, or tan. select the correct statements regarding the mode of inheritance of the coat color genes. a) both genes are x-linked. b) both genes are autosomal. c) one of the genes modifies the expression of the other gene. d) each gene has an additive effect on the intensity of coat color. e) each gene independently specifies three colors. f) one of the genes is autosomal, and the other is x-linked.

Which entry is in the wrong position in the table?

Based on the topographic map of mt. st. helens, what is the contour interval of the volcano about height is 2,950 m?