Answer:
D.) Organism
Explanation:
On the basis of biological organization, one female arctic fox will be considered as an organism.
Biological organization refers to a hierarchy starts from simplest biological structure to complex biological structures that define life, such as from atoms to biosphere.
So, biome is the community of animals and plants having common characteristics according to the environment; species is also a group of living organism sharing similar genes; ecosystem include different groups with the physical (abiotic) environment and organism is the basic living system,that include at least one cell.
So, one female arctic fox will be termed as an organism and the correct option is D.
Circulatory and Respiratory systems working together to provide body with oxygen.
Answer:
(B) calmodulin
Explanation:
Calcium in cells acts as second messenger molecule which regulates the very important physiological and cellular process of cell-like neurotransmission, cell migration, secretion, fertilization and many others.
Calcium acts as a messenger by binding to a calcium-binding protein called calmodulin. Calmodulin forms complex with 4 calcium ions through the side amino acids present in the structure of calmodulin.
Thus, calmodulin is the correct answer.