<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.
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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?
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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".
Answer:
A mutation is generally referred to as certain alternations in the gene whether it may be DNA sequences, which may be beneficial, harmful or of no significance to the mutant gene bearing organisms.
Explanation:
- A mutation that increases the ability to store moisture in a dry environment is obviously beneficial. Because it prevents dehydration and maintains normal functioning in spite of adverse conditions.
- A color mutation that decreases a bird's chances of sexual selection is beneficial in the sense that it prevent certain abnormalities in offspring like sexual dimorphism. Also sexual selection often proves to be a threat to the survival of the organisms as per handicap principle.
- A mutation in non coding region of DNA is harmful, as it is often observed to facilitate expression of wrong proteins at inappropriate places.
- A mutation in the that does not changes protein synthesis increased white pigmentation on a prey animal in snowy environment as it had prevented adaption of the prey and hence harmful for survival of it.
- A mutation decreasing plant's height in competition to light, makes them less exposed to sun energy important for photosynthesis and hence it is harmful for the plant.
Answer:
This can be explained based on structure, and on metabolisms of carbohydrate.
Explanation:
Carbohydrate has a relatively simple structural composition than the either protein or fatty acids. The C, H and Oxygen molecules are of relatively fewer in number and few chains than fats and protein.Thus cells will spend less energy to break bonds(catabolisims) among these molecules during cellular respiration pathways to trap the energy.
In addition glucose the end products of carbohydrate did not need any processing before it enters glycolysis, Kreb's Cycle and oxidative phosphorylation pathways to generate energy for the cells.
Conversely, for protein to be used it has to be first deaminated(removal of amino acid) by the liver before it enters glycolysis,while fats needs to be broken down and undergo beta oxidation with the long chains removed before it can form acetyl CoA. Therefore cells will prefer few steps, less endergonic pathways of glucose than longer more endergonic amino acids and fatty acid pathways.
Furthermore, glucose can be used in cellular respiration to produce energy either aerobically or anaerobically, while fats can only be used anaerobically. Therefore, since cells usually prefer to thrive in aerobic conditions they breakdown glucose easily during this period, and when lack of oxygen occurs they switched to anaerobic, Thus, the versatility of glucose to oxygen concentration makes glucose a better choice. Besides if fats was used anaerobically, ketone bodies build up which may be toxic to the cells.
Answer:
Near water, change in elevation, or change in latitude.
Explanation: