The correct answer is absence of jaws.
Lampreys and hagfish are in the class Agnatha, they are jaw-less fish. The members of the agantha class are probably the earliest vertebrates. Scientists have found fossils of agnathan species from the late Cambrian period that occurred 500 million years ago.
Answer:
I am expecting that option c or d is correct
<span>The normal daily input of water is about 2.5 L from beverages food, and metabolism. The normal daily output of 2.5 L consists of 1.8 L in urine, sweat, and feces, plus 0.7 L in insensible water loss. Insensible water loss is water that evaporates through the skin and from the respiratory tract. Insensible losses account for 0.7 L of water loss per day. The average human exhales an average of 0.35 L of water each day. This corresponds to about 14% of water lost through respiration.</span>
Answer:
In an ancestral elm species, mutations gave rise to the phenotypic trait "winged-seeds". Subsequently, selection favored elm plants with winged-seeds that diverged over time to become a separate species
Explanation:
A mutation is a genetic change in the DNA sequence. In general, mutations have a negative impact on the fitness of the individual (i.e., mutations are generally deleterious) and therefore they disappear from the population. However, there are situations where mutations are beneficial and confer an adaptive advantage, thereby increasing their frequency in the population. In this case, mutations associated with the formation of winged-seeds conferred an adaptive advantage (i.e., higher seed dispersal capacity) to individuals who had this phenotypic trait, thereby these individuals had more chances to reproduce and pass their genes to the next generation. Eventually, Elm plants with winged-seeds accumulated sufficient genetic differences to prevent interbreeding, leading to the formation of a separate species.
Carbon forms Covalent Bonds.