Answer: The correct answer is B) Native shellfish populations have dramatically decreased as they are outcompeted by the crabs, causing a decrease in biodiversity.
Explanation: Green crabs represent a serious threat to biodiversity in the ocean ecosystem because they are predators that feed with animals that are part of the biodiversity such as clams, mussels, and oysters. As the predators they are, they can dramatically change the ecosystem by affecting the living and reproduction of many species.
Answer:
Habituation.
Explanation:
Habituation may be defined as a type of non associative learning. This type of learning reduces the innate response of an individual towards the repeated or prolonged time of the stimulation.
The frog first respond to the tree branches swaying in the wind. After some time the frog does not respond because of the prolonged or repeated stimulus of the environment. Hence, frog shows the lack of response due to habituation.
Answer:
Disruptive selection
Explanation:
Disruptive selection, also known as diversifying selection, describes changes in population genetics where extreme values for a trait are favored over intermediate values. In this case, the variance of the trait increases and the population is divided into two distinct groups. In this more individuals acquire peripheral character value at both ends of the distribution curve.
Helper T cells are found in the <u>Thymus.</u>
Explanation:
Immature T-cells are formed in the bone marrow, just like any other blood cells, through the process of hematopoiesis. These immature T cells are then transported to the thymus where they mature and differentiate into the different types of T cells; cytotoxic, helper and regulatory. T-helper cells, also called CD4⁺ cells, are important in activating B-cells and T-cytotoxic cells in case of infection.
Answer:
Changes in the genes DNA sequence can change proteins by altering their amino acid sequences, which may directly affect one's phenotype.
Explanation: