The correct answer is - No.
The Cambrian explosion is a term used for the big and rapid diversification of the animal species, but it is not the period in which the animal life started. The animal life started in the period between 620 and 550 million years ago, in what is known as the Vendian Period. In the Vendian Period, the first complex animal organisms appeared, started to develop and evolve, though it is not a period where there was a high diversification of the species. The later Cambrian Period provided better living conditions, and that resulted in a so called ''explosion of life'', which resulted in much more new species developing and evolving.
Answer: Sea stars move using a water vascular system. Water comes into the system via the madreporite. It is then circulated from the stone canal to the ring canal and into the radial canals.
Explanation: The radial canals carry water to the ampullae and provide suction to the tube feet.
Answer:
a.Brain
Explanation:
Hypothalamus: The hypothalamus is in the lower central part of the brain. It links the endocrine system and nervous system. Nerve cells in the hypothalamus make chemicals that control the release of hormones secreted from the pituitary gland.
Adaptation is supported by Darwin's observation of local
variation among tortoises in the Galapagos Islands.
<span>In biology, an </span>adaptation, also called an adaptive trait, is a trait with a
current functional role in the life of an organism that is maintained and
evolved by means of natural selection. Adaptation<span> refers
to both the current state of being </span>adapted<span> and
to the dynamic evolutionary process that leads to the </span>adaptation.
The correct answer between all
the choices given is the second choice or letter B. I am hoping that this
answer has satisfied your query and it will be able to help you in your
endeavor, and if you would like, feel free to ask another question.
A grow and divide uncontrollably.