Answer:
While doing medical research on the human subject, following limitations are unavoidable:
a). Privacy: The privacy of the subject involved in the research should be maintained.
b). the subject must be allowed to the minimal exposure to risks and it must be tested on animals first to avoid deaths.
c). The risk associated with the physiological and physical well being of the subject must be considered.
d). The subject must be well instructed about all the risk and procedure involved in the research.
The correct answer is B. Ordovician period
Explanation:
Plants are mainly multicellular organism that depends mainly on photosynthesis to obtain energy, this includes a wide variety of species such as grass, flowering plants, trees, shrubs, etc. Additionally, plants are considered as one f the two major divisions or kingdoms along with animals. In terms of history, it has been determined first land plants appear during the mid-Ordovician period around 470 million ago, although organisms that were the origin of land plants developed in water in previous periods, also by the Devonian period a wide variety of plants have emerged with features that are still part of plants nowadays. Therefore, plant life first appeared on land during the Ordovician period.
Answer: because the structure of their cell wall is unable to retain the crystal violet stain
Explanation:
Due to differences in the thickness of a peptidoglycan layer in the cell membrane between Gram-positive and Gram-negative bacteria, Gram-positive bacteria (with a thicker peptidoglycan layer) retain crystal violet stain during the decolorization process, while Gram-negative bacteria lose the crystal violet stain
Learning ways to manage stress effectively
Answer:
Because different cells are under different pressure. The most frequently replaced cell would be skin cells while on the opposite scale we have neurons. Skin is under constant pressure so we have to replace it as quickly as possible where as neurons must be replicated only once so we can maintain a stable brain.
Explanation:
