The pair of characteristics that one must use to classify a fish is the presence of jaw and skeleton type. Agnatha fishes are also called jawless fishes and they lack bony skeletons. Cartilaginous fishes are composed of cartilage skeletons. Bony fishes have bony skeleton structures.
Answer:
Cell theory
Explanation:
Also known as the cell membrane.
Answer:
Look like palm trees
Explanation:
Cycads are an ancient group of seed plants with a crown of large compound leaves and a stout trunk. They are a minor component of the flora in tropical and subtropical regions today, but during the Jurassic Period, they were a common sight in many parts of the world.
While on the other hand,
The Pinophyta, also known as Coniferophyta or Coniferae, or commonly as conifers, are a division of vascular land plants containing a single extant class, Pinopsida. They are gymnosperms, cone-bearing seed plants. All extant conifers are perennial woody plants with secondary growth.
Answer: This is a hard question because we need copper for just about anything. Some people say that electric cars are better because the conserve fuel, but they have copper. The source of all of our power (electricity) stems from copper. Simply said, no matter what you do to conserve copper, you are still going to need it and use it.
Explanation:
The correct answer is testosterone.
A chemical messenger simply refers to a hormone.
Testosterone is a lipid - based hormone. In fact, it is an anabolic steroid . Steroids are a type of lipid which has four rings of carbon atoms.
Testosterone is a hormone produced by the Leydig's cells in the testes, and which encourages the development male sexual characteristics such as deep voice, a beard, increased muscle mass and bone mass, and growth of hair on the chest.