The correct answer is:
C) outer covering
The structure that you should expect to find in a single celled organism is : C. outer covering.Single celled organism still hasn't developed a complex body structure, so it definitely won't have legs, internal organs, or brain.
Explanation:
None of the other answers can happen due to the combined solutions disability to reach the center of the organism, smaller cells in higher numbers are more effective as they can group commonly yet all receive the right amounts of nutrients for its need. multicellular organisms, such as humans can have the other answers in them as cells group collectively to make skin, muscles, and organs. it also provides the body to grow larger.
Pectinate muscles are parallel ridges in the walls of the atria of the heart. The name is due to their resemblance to the teeth of a comb (pecten). The heart is the organ pumps blood to all parts of the body. It is made up of four chambers, that is, right and left ventricles, left and right atria, and the blood vessels, Pulmonary artery, pulmonary vein, aorta, and venacava. An auricles are pouch like structure that increase the total filling capacity of the atrium and also increase the volume of blood that an atrium is able to contain.
Answer:
b. They express the appropriate receptor.
Explanation:
The signal transductions are extraordinarily specific and sensitive. Specificity is achieved by a <u>precise molecular complementarity between the signal molecules and the recepto</u>r. For example, the thyrotropin-releasing hormone produces a response in cells of the adenohypophysis, but not in hepatocytes, which lack the receptors to this hormone.
Characteristics of Lancelets:
Small
Elongated
Marine invertebrate
Lacks a jaw
No sense organs
Has a notochord
Example: Lamprey
Characteristics of Tunicates:
Marine invertebrate
Has an outer coat that is rubbery or hard
Has two siphons
Examples: sea squirts, salps
I hope this is the answer that you were looking for.