<h3><u>Answer;</u></h3>
The above statement is <u>False </u>
<h3><u>Explanation;</u></h3>
- Speciation is an evolutionary process in which new species arise. There are three types of speciation, namely; sympatric, parapatric and allopatric speciation.
- <em><u>Sympatric speciation is a pattern in which speciation occurs in the absence of a physical barrier to gene flow; ex. polyploidy arising in flowers.</u></em>
- In an Allopatric speciation on the other hand, a physical barrier arises and separates two populations, ending gene flow between them and allowing reproductive isolating mechanisms to evolve so that later if the two groups come back into contact they will no longer be able to reproduce together, therefore making them different species.
Answer:
A. is correct
Explanation:
Low-pressure systems are associated with volatile weather conditions like clouds and rain. This is exactly what A says. Hope this helps :)
Answer:
D. Rounded grains cemented together by dissolved mineral.
Answer: unfavourable ph condition for the pepsin
Explanation: during digestion, enzymes are needed to aid the process.digestive enzymes are biological catalyst that breakdown large food particles into digestible form .
As biological catalyst, enzymes require an optimum temperature and pH condition.outside this temperature or pH,the enzyme is denatured.
In the stomach, hydrochloric acid is required to convert pepsinogen into it's active form,pepsin.the acid also creates an optimum low pH that pepsin needs to function.
As the food moves to the small intestine,the pH is alkaline and is unfavourable for pepsin to function.
18mg for a 19-50 year old adult female.
