Answer:
The correct answer is - freshwater snails.
Explanation:
Producers are organisms that produce their own food and not depends on any other organism by the process of photosynthesis such as algae. Primary organisms on the other hand directly depend on the producers for their food and often gt killed by secondary consumers.
Freshwater snails are the perfect example of the primary consumer as they get their food and energy from algae and are the primary source of food and energy for small fishes.
Answer: Meselson & Stahl reasoned that these experiments showed that DNA replication was semi-conservative: the DNA strands separate and each makes a copy of itself, so that each daughter molecule comprises one "old" and one "new" strand. The semi-conservative model, in which each strand of DNA serves as a template to make a new, complementary strand, seemed most likely based on DNA's structure. ... From the patterns of DNA labeling they saw, Meselson and Stahl confirmed that DNA is replicated semi-conservatively.
Explanation:
Hormones are the chemicals that play important role in human body. The changes in human body is mainly related to the hormonal changes. In case of a female, hormones play a very significant role. If the diet is unhealthy or laden with extra hormones or chemicals that mimic hormones, the female my experience and early puberty. In such case, the menarche can be reached earlier than expected.
Thus, diet laden with hormone mimicking chemicals are expected of contributing to girl's earlier experience of menarche.
What it eats, what weather it's build for and DNA
Answer:
The correct option is A. they evolved from land mammals.
Explanation:
Evolution can be described as a process through which organisms in a species change over a period of time due to the natural selection of the environment. Those organisms that have many similarities in their functions or structures are considered closer to one another and have the same common ancestors.
The properties mentioned in the question about cetaceans resembles the properties of land mammals. For example, cetaceans lack gills and breathe air. Land mammals also do not have gills and need to respire for living. The cetaceans have fin bones which are similar to the limb bones in the land mammals. Hence, these observations show that cetaceas have evolved from land mammals.
