The phylum Echinodermata , which contains about 6000 species, gets its name from the Greek, literally meaning "spiny skin." Many echinoderms actually do have "spiny" skin, but others do not. This phylum exists exclusively in the sea, and cannot be found on land or in fresh water. All echinoderms have one thing in common: radial symmetry. This means that the creatures have appendages (or body construction) which point outward from the center of the body like the spokes on a bicycle wheel. Furthermore, these appendages usually occur in multiples of five, although there are a few exceptions. There are several well known members of this group, like sea stars and sea urchins. The radial symmetry is obvious in these creatures.
Answer:
The exosphere and the ionosphere
Answer:True
Explanation:the electron transport chain can be considered to be an aerobic pathway because it utilizes free oxygen as its final electron acceptor. These free oxygen is liberated by intermediate glucose molecules.
Answer:
Option D
Explanation:
Diagram is attached.
Capsid protein is a form of structural protein which usually forms part of a complex which later produces protective shell around the nucleic acid in a virus. It is also referred to as coat protein or head protein.
Capsid acts as a distinguishing feature for identifying an integrated viral genome, plasmids and other genetic material of viruses. In fact, viruses are termed as organisms that encode capsid proteins.
Hence, option D is correct
Answer:
The coral reefs of the Caribbean are thought to be under threat
Explanation:
Overfishing threatens over 60 percent of Caribbean coral reefs. Declines in coral cover and increases in algal cover have been observed across the region. This analysis identified about one-third of Caribbean reefs at high threat from overfishing pressure and about 30 percent at medium threat.