Correct Answer: D. Intensity of stimulus must reach a threshold value before the neurons can be excited

Correct Answer: D. Iodine solution

Correct Answer: A. water cycles

Correct Answer: C) pulmonary breathing

Explanation

Cutaneous breathing is through the skin, buccal is through the mouth while larynxial is through the larynx. Pulmonary deals with the lungs.

Correct Answer: D. Diatom -> crustacean -> fish -> man

Correct Answer: D. 0.16

Explanation

This is a Hardy-Weinberg Equilibrium problem. The question stem gives you the prevalence of the dominant allele, 0.6. The prevalence of the dominant allele and the prevalence of the recessive allele must always add together to equal 1: p+q=1 So, the prevalence of the recessive allele must be 0.4: p=0.6 p+q=10.6+q=11?0.6=0.4 The prevalence of the recessive phenotype is equal to the prevalence of the recessive allele squared: q2=0.42=0.16 In this case, black coat color is a recessive trait, so the prevalence of this recessive phenotype is equal to the prevalence of the recessive allele squared, or 0.16.

Correct Answer: C) pistil (gynoecium)

Explanation

In order for a flower to undergo pollination and form a fruit, certain parts of the flower are essential. The question is asking which part(s) are necessary for this process. The options to choose from are corolla, ovary, pistil (gynoecium), ovules, and receptacle. The corolla is the part of the flower that consists of the petals. While the petals may be important for attracting pollinators to the flower, they are not essential for pollination or fruit formation. The ovary is the part of the flower that contains the ovules and eventually develops into a fruit. While the ovary is important for fruit formation, it is not the only essential part. The pistil, also known as the gynoecium, is the female reproductive part of the flower. It consists of the stigma, style, and ovary. The stigma is the sticky surface that captures pollen, the style is the stalk that connects the stigma to the ovary, and the ovary contains the ovules that become the seeds. The pistil is essential for pollination and fruit formation. Ovules are the structures within the ovary that develop into seeds after fertilization. While ovules are necessary for seed production, they are not the essential part for pollination and fruit formation. The receptacle is the base of the flower to which all parts of the flower are attached. While the receptacle is important for providing support to the flower, it is not essential for pollination or fruit formation. Therefore, the correct answer to the question is option C, the pistil (gynoecium), as it is the essential part of the flower for pollination and fruit formation.

Correct Answer: C. Codominance

Explanation

The child is blood type AB, meaning that the child has both the A antigen and the B antigen on his or her red blood cells. The child is able to express the products of both genes simultaneously. The A antigen was inherited from mom, and the B antigen was inherited from dad. The A and B alleles are codominant because they can both be expressed in the same person at the same time if the person inherits both alleles, as is the case in this example.

Correct Answer: B. to complement gills while on land

Correct Answer: A. how easily water passes through the soil