Answer: Gemstones of various minerals are highly prized for beauty, durability, and rarity. Some noncrystalline materials of organic origin. Examples are pearl, red coral, and amber also are classified as gemstones. Gemstones have attracted people since the ancient times, and have been used for jewelry.
Explanation:
I would say that it's B. But that is not for sure.
Answer:
Allopatric speciation occurs due to the geographical isolation between individuals of the same species. The geographical isolation can be due to canyon development, mountain formation, migration, etc.
The geographical isolation gives different environmental condition to the separated population of same species to live which allow these two population to evolve differently and evolve in different species.
So when two population becomes different species and not able to interbreed with each other when give opportunity then the allopatric speciation between the two populations becomes complete.
Answer: Valves in the veins
Explanation: The flow of the blood inside the body takes place through the veins and arteries. The oxygenated blood from the heart is supplied to the different parts of the body.
The blood flows from the capillaries to the venules and from there to the veins. The blood moves in the veins by the rhythmic movement of the smooth muscles in the body.
Most of the blood moves against the gravity so there is a chance that it can backflow so to prevent this there are valves in the veins known as one way valves.
Answer:. The genotype is RB(the gene)
The phenotype is purple(the physical appearance)
None of the flowers will be red
All will be purple.
None will be blue
Note: the crossing above indicates a case of co-dominance