<span>d. by sending and detecting chemical messages</span>
Answer:
The correct answer would be C. The tortoises provided evidence that different species have adaptations suited to their particular environments.
Darwin observed that how different environment on different island lead to the development of different species as a result of adaptations and natural selection.
For example, tortoise inhabiting well-watered islands which used to have short and cropped vegetation had developed a dome-shaped shell.
In contrast, the tortoise inhabiting the arid islands had developed saddle-shaped shells. It is because they needed to stretch their necks in order to reach branches of cactus and other vegetation available in the area.
Consequently, they developed long necks and high peak to the front edges of their shells. It made it possible for them to stretch their heads vertically.
One sperm fertilizes the egg cell forming a diploid zygote, the other sperm fuses with the two polar nuclei forming a triploid cell that develops into endosperm
Answer:
B
(The result of DNA replication is two DNA molecules consisting of one new and one old chain of nucleotides. This is why DNA replication is described as semi-conservative, half of the chain is part of the original DNA molecule, half is brand new.)
The items needed to complete a circuit include the following:
<h3>Functions of the parts of a Circuit.</h3>
The wire helps in the distribution of the electric current from the power
source in order to ensure it gets to the load.
The battery contains compounds which is responsible for providing the
energy required to power up the load.
The load could be a bulb, fan etc and is the final destination of the electric
current. The electric current powers up the load and makes it functional.
The switch helps to regulate the flow of electric current and has an 'on and
off button' to prevent energy wastage when not in use.
Read more about Circuit here brainly.com/question/2969220