They increase in number and they are more specialized
"Answer DThe outermost layer of old epidermal cells are sloughed off and replaced every 15 to 30 days. The sebaceous glands secrete sebum which maintains the skin pH between 3 and 5. Bacteria which metabolize sebum live as opportunistic pathogens on the skin and cause skin infections."
Xylem Phloem are the vascular tissues that transport the food, minerals and water within the plant. Xylem transport the water and minerals while Phloem transport food and nutrients. The movements in Xylem is unidirectional from roots to aerial parts while the movements in Phloem are bidirectional.
Increased frequency of homozygous genotypes
Answer:
The preferable option will be - A.
A. similar environments and specific traits increased their chances of survival.
Explanation:
- The shark and dolphins have similar body shape and fins. But shark is a fish and dolphin is a mammal.
- Both of them are exposed to similar kind of environments. Both of them possess a specific kind of alternative characters and traits.
- So, Some species may have similar body structures even if they are not related because they evolved in similar environments and specific traits increased their chances of survival.
