Answer:
Question 1
D
Question 2
C
Question 3
D
Explanation:
1. An ecosystem is MOST likely to return to its original condition after Tall prairie grass burns after being struck by lightning.
Here is a research paper in which they explained how this happened. (Komarek, E. V. (1971). Lightning and fire ecology in Africa. In Tall Timbers Fire Ecology Conference (Vol. 11, pp. 473-509).)
2. In some national parks, controlled fires are maintained by firefighters. The major reasons for using controlled burns to maintain certain ecosystems is to give nonnative plants a chance to colonize the region.
A recent article provided the insight of this situation (Xanthopoulos, G., Delogu, G. M., Leone, V., Correia, F. J., & Magalhães, C. G. (2020). Firefighting approaches and extreme wildfires. In Extreme Wildfire Events and Disasters (pp. 117-132). Elsevier.)
3. One reason for the change in the Galápagos ecosystem has been the introduction of species that were not on the island before, such as donkeys, goats, cats, dogs, and insects. The introduction of nonnative species MOST likely disrupt the balance of life on the islands due to greater competition for limited food sources.
Scientist said that food competition is actually a struggle to survive in any ecosystem here is the reference paper (Eckhardt, R. C. (1972). Introduced plants and animals in the Galapagos Islands. Bioscience, 22(10), 585-590.)
If a hypothesis is supported it becomes a theory if its not he or she has to make another hypothesis
Answer:
rRNA is located in the cytoplasm of a cell, where ribosomes are found. rRNA directs the translation of mRNA into proteins.
<h2>The given statement is true</h2>
Explanation:
Iron absorption occurs in the duodenum and upper jejunum of small intestine
- At physiological pH ferrous iron is rapidly oxidized to the insoluble ferric form
- Gastric acid lowers the pH in the duodenum which enhances the solubility and uptake of ferric iron
- Once iron gets inside the enterocyte it can be stored as ferritin;Ferritin is a hollow spherical protein which helps in storage and regulation of iron levels within the body
- Ferritin molecule have ferroxidase activity which helps in the mobility of Fe2+ out of the enterocyte by ferroportin
- Transferrin is the major iron transport protein which transports iron through blood
- Fe3+ binds to transferrin so Fe2+ transported through ferroportin must be oxidized to Fe3+
- Fe2+ needs to be oxidized first so that it can be transported through ferroportin
- Once iron gets inside the cell it can be used for various cellular processes
