D) differences between species and their ancestors
This is because of the adaptive mechanism and mutations the organisms have to respond to. <span>Adaptation processes occur to help species survive and thrive in the ecological balance of life. Structural adaptations are physical features of an organism that adapted through time. An example of this are the bills of a bird and the fur of bears that they generally need for their survival; birds for hunting, and bears to protect them from low climate areas.</span>
C. The digestive system breaks down food and the circulatory system transports the nutrients throughout the body.
The Digestive system is the system that helps the body digest food. It consists of the following organs: liver, stomach, gallbladder, large and small intestines, pancreas, rectum, and esophagus.
The Circulary system is the system that pumps blood through body. The blood contains all the nutrients and minerals the body needs. The system consists of the following organs: heart, blood vessels, blood, lymph, lymphatic vessels, and glands.
Answer:
A) A mutation in a single gene can result in a defective protein.
Explanation:
This hypothesis states that one gene codes for one protein-enzyme, so consequently, if mutation occurs in that gene, the enzyme will not work properly. This hypothesis was very important for the fundamental discoveries of molecular biology, but it is oversimplified meaning that relationship between genes and proteins is much more complex.
A. Community.
This is because a community contains living this, and biotic means living.