Answer: a. True
Explanation: These postulates were formulated by Robert Koch as a result of his experiments with healthy and infected mice. The postulates are often used to determine if a phatogen causes a disease. These are:
- The pathogen must be present in sick individuals but not in healthy ones.
- The pathogen must be isolated from individuals and cultivated in a pure culture.
- The pathogen cultivated must cause sickness when it's injected in suceptible inviduals.
- The pathogen must be isolated from the injected individuals and must be exactly as the first one.
Answer: Option B) No, even though the DNA sequence changed, the sequence still codes for the same amino acid, so no change in phenotype will occur.
Explanation:
Since the triplet codon ACG codes for the amino acid threonine, so also ACA codes for threonine, the single base change of Guanine (in ACG) to Adenine (ACA) is insignificant due to the degeneracy of the genetic code.
Thus, the sequence still codes for the same amino acid, so no change in phenotype will occur
Answer: The cell is the structural and functional unit of all living organisms, and is sometimes called <u>the "building block of life."</u> Some organisms, such as bacteria, are unicellular, consisting of a single cell.
Ecosystem is a community or group of living organisms that live in and interact with each other in a specific environment.
An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system. These biotic and abiotic components are linked together through nutrient cycles and energy flows.
Is this multiple choice?!