The first living things on Earth, single-celled micro-organisms<span> or microbes lacking a cell nucleus or cell membrane known as prokaryotes, seem to have </span>first<span> appeared on </span>Earth<span> almost four billion years ago, just a few hundred million years after the formation of the </span>Earth<span> itself.</span>
The answer to this question would be: vertebrae
In vertebrae fracture, traction is important to assure immobilization of the vertebrae. Movement can cause the fragment of bone in the fracture damaging the neural tissue in the vertebrae.
To ensure no movement in the neck, metal tongs can be put on the skull. The tongs will help fixate the skull with the shoulder.
Answer:
c. CNS
Explanation:
The Central Nervous System (CNS) is responsible for receiving and transmitting information throughout the body. We can define it with the command center that coordinates the activities of the body. It consists of the brain and spinal cord, which are protected by the skull and spine respectively.
Both structures are reinforced by three connective blades, called meninges. They are: dura mater, arachnoid and pia mater. Between the last two there is a fluid that is responsible for the nutrition of the CNS and the minimization of possible trauma caused by mechanical shocks.
Answer:
Prezygotic barriers:
1. Habitat isolation
2. Behavioral isolation
Explanation:
Pre-zygotic barriers are the barriers which do not allow the formation of the zygote in the organisms.
The two mechanisms of the pre-zygotic barriers are the:
1. Habitat isolation: the Flycatchers do not share the same habitat which is also mentioned in the question that they live on different islands.
2. The behavioural isolation: the Flycatchers could have evolved the different mating rituals as a result of which the could not interbreed.
Thus, Habitat isolation and Behavioral isolation are correct.
