Henry was studying two populations of the same species of lizards. One population lived on an island and the other lived on the mainland. Both populations were affected by a hurricane that hit the island and the mainland with equal force. A year later, Henry was testing the gene frequency and saw a decrease in genetic variation in the island species, but not in the mainland species. Which best describes a conclusion he might have reached? Gene flow greatly affects small populations, but large populations can recover. Genetic drift greatly affects small populations, but large populations can recover. Gene flow greatly affects large populations, but small populations can recover. Genetic drift greatly affects large populations, but small populations can recover.

The correct option is Genetic drift greatly affects small populations, but large populations can recover.

Explanation:

Genetic drift is an evolutionary mechanism in which the allelic frequencies in a population change through many generations. Its effects are harder in a small-sized population.  

Genetic drift results in some alleles loss, even those that are beneficial for the population, and the fixation of some other alleles by an increase in their frequencies. The final consequence is to randomly attach one of the alleles.  

Genetic drift has important effects on a population when this last one reduces its size dramatically because of a disaster -bottleneck effect- or because of a population split -founder effect-.

In the exposed example, the hurricane caused a disaster in both populations, reducing the number of individuals on the island and in the mainland. Henry saw a decrease in genetic variation in the island species, but not in the mainland species. This could be because the island population was smaller than the mainland population, so it was more affected by the disaster. The loss of some alleles in the population caused a decrease in genetic variation in the island population.

The answer is B.

Explanation:

The bottom two answers don't make sense and the first one is unrelated.

question#1

ans:

cell is the basic unit of organization of all living things. cells are often called the building block of life and it is the smallest unit of life. the study of cell is called cell biology. cell consists of cytoplasm enclosed within membrane, which contain bio-molecules such as proteins and nucleic acid.

two third of cell is water, which means that two-third of your whole body is water. the rest is the mixture of molecules, mainly proteins, lipids and carbohydrates.

question#2

ans:

organ:

an organ is a group of tissues specialized to form a functional unit. an example is the heart in animals.

organ system:

an organ system is a group of several organs whose functions are synchronized to release an effective action in a living organism. an example is digestive system.

question#3

different systems perform different function at tissue level. for example, the respiratory system facilitates breathing. in the alveoli tissue of the lungs, the exchange of oxygen and carbon dioxide molecules between the air and the bloodstream occurs by passive transport, so that oxygen is taken in and carbon dioxide and water are removed. different systems of the body carry out different functions. for example, your digestive system is responsible for taking in and processing food, while your respiratory system working with your circulatory system is responsible for taking up oxygen and getting rid of carbon dioxide.

question#4

different systems perform different function at tissue level. for example, the respiratory system facilitates breathing. in the alveoli tissue of the lungs, the exchange of oxygen and carbon dioxide molecules between the air and the bloodstream occurs by passive transport, so that oxygen is taken in and carbon dioxide and water are removed. different systems of the body carry out different functions. for example, your digestive system is responsible for taking in and processing food, while your respiratory system—working with your circulatory system is responsible for taking up oxygen and getting rid of carbon dioxide.

question#5

our body works because of the interactions that happen between organs and organ systems.  

for example:  

the heart to regulate blood flow throughout the body. the blood carries oxygen and nutrients to the cells and carries carbon dioxide and waste away from the cells. body systems work together in maintaining a constant internal environment. when this balance is disrupted, the body systems may not function properly, and human health can suffer.   you start to feel bad.