How can pets affect vernal pool creatures?

Vernal pools are unique wetland habitats where some of the state’s most recognizable reptiles and amphibians can be found. Vernal pools are small, shallow wetlands that do not have a permanent inlet or outlet of water flow. They fill in the fall or spring when rain or snowmelt drains into shallow depressions, and can retain water due to non-porous soils. Vernal pools only hold water for part of the year and experience a drying phase every year or every few years, usually in late summer.

Because their aquatic habitats are temporary, animals that depend on seasonal pools are adapted for both aquatic and terrestrial habitats at different life stages. These animals also benefit from the dry phase, because it prevents year-round water-dependent animals like fish from living in the pools. Fish prey heavily on eggs and larvae, and without seasonal pools some species would not be able to compete and reproduce. Although there are obvious challenges for an animal using an aquatic environment that disappears for part of the year, the benefit is a habitat free from predation by fish.

answer: b: experiments that showed that all cells are similar in how they metabolize and in their composition

explanation:

an individual’s sex (i.e., whether they are a male or female) is determined by the sex chromosomes. most people have two sex chromosomes, one that is inherited from their mother and one that is inherited from their father. typically, females have two x chromosomes (xx) and males have one x chromosome and one y chromosome (xy). conditions caused by changes (“mutations”) in genes located on the x chromosome are considered x-linked.

x-linked recessive inheritance

most x-linked conditions are recessive. this means that in a person with two x chromosomes (most females), both copies of a gene (i.e., one on each x chromosome) must have a change or mutation whereas in a person with one x chromosome (most males), only one copy of a gene must have a mutation. a female with a mutation in one copy of a gene on the x chromosome is said to be a “carrier” for an x-linked condition. a male with a mutation in a gene on the x chromosome is typically affected with the condition. because females have two copies of the x chromosome and males have only one x chromosome, x-linked recessive diseases are more common among males than females. however, x-linked recessive diseases can occur in both males and females.

for x-linked recessive disorders, an unaffected carrier mother who has a mutation in a gene on the x chromosome can transmit either the x chromosome with this mutation or a “normal” x chromosome to her children. if the father is unaffected, none of her daughters will be affected and all of her daughters will be unaffected—since they will inherit at least one normal x chromosome from their father. however, each daughter will have a 50% chance of being an unaffected carrier like her mother and a 50% chance of both x chromosomes being normal.