<span>1. List five observations Darwin made about the Amblyrhynchus lizards.
a. They measure about 2-3 feet long.
b. They are cold-blooded.
c. They feed on crab and sea lion feces.
d. They are the only marine iguanas in the world.
e. Their nostrils are connected to salt glands that allow them to expel excess sea salt.
</span><span>2. Describe two examples of structural adaptations that Darwin observed.
a. </span><span>Darwin discovered that finches in the Galapagos have thirteen different kinds of beaks.
b. </span>Darwin observed two kinds of giant tortoises that are distinguished by the shapes of their carapaces (dome-shaped and saddle-shaped).
3. <span>Describe two behavioral adaptations that Darwin observed.
</span>
a. <span>The marine iguanas have developed several ways of coping with the cold. At night, they huddle together for warmth.
b. </span>In the face of famine, the marine iguanas have adapted by having the ability to shrink their body size. They are able to grow back to their original size once the food is supply increases.
4. <span>Explain how these observations influenced his theory of evolution?
</span>
These observations led Darwin to believe that if a certain trait is more advantageous in a specific environment, then the carriers of that trait are more likely to survive into adulthood and to generate offspring than those who do not have that trait. Eventually, the advantageous traits for a species will proliferate. Darwin later called this as "survival of the fittest".
The two events that occur when gravity causes a nebula to collapse into itself are:
A. Nuclear fusion start.
B. A new star forms.
Explanation:
- Nebula are giant clouds of dust and gases.
- These clouds are considered as progenitors of stars and planets.
- The gravitational pull within these giant clouds result these large masses to collapse towards their centre.
- The gravitational collapse results in tremendous rise in temperature till a point where nuclear fusion begin .
- The stars are born out of such mechanism and act as a source of heat and light in universe.
Answer:
DNA structure DNA is made up of molecules called nucleotides. Each nucleotide contains a phosphate group, a sugar group and a nitrogen base. The four types of nitrogen bases are adenine (A), thymine (T), guanine (G) and cytosine (C).
Explanation:
True. Since electron microscopes use electrons instead of light, it can magnify up to 500,000 times of it’s actual size.
Use of transgenic animals to improve human health and animal production. ... The advance in the generation of pigs to be used as the source of organs for patients and in the preparation of pharmaceutical proteins from milk and other possible biological fluids from transgenic animals is described.
