Answer:
The liver regulates most chemical levels in the blood and excretes a product called bile. This helps carry away waste products from the liver. All the blood leaving the stomach and intestines passes through the liver.
Answer:
Option E, Smooth muscle contractions that move food along the esophagus.
Explanation:
Peristalsis is an involuntary movement of muscles (smooth and longitudinal) in the digestive tract to move the food from Oseophagus to other hollow tubes and stomach.
These Peristaltic waves are strong wave like smooth muscle movement in the esophagus, stomach, and intestines as the bolus of food is swallowed to process food in different digestive tract.
Hence, option E is correct
<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".
Answer:
The two important conditions that must be met before gram staining are-
1. The age of the culture should not exceed 24 hours.
2. Over heating, decolonization should be avoided.
Explanation:
Gram staining is a technique developed to distinguish the bacteria on the basis of the composition of the cell wall around the bacteria.
The gram stain is a sensitive technique so must be performed carefully. The precautions should be taken to avoid any error while gram staining that is-
1. Age of the culture- The culture should be freshly prepared just 18-24 hours before the experiment as above 24 hours bacteria lose their ability to retain the color so one would not be able to differentiate between the cultures.
2. While performing the experiment one should avoid overheating and decolorization with ethanol as both the factors lead to the loss of crystal violet stain from the cell and they take pinkish color after safranin staying.
