Answer:
4. The suspected causative agent must be isolated from the diseased host and grown in pure culture
Explanation:
Robert Koch (1843-1910) was one of the most important bacteriologists of all time. Famous for discovering the tuberculosis bacillus (precisely on March 24, such as today, in 1882), he also discovered the cholera bacillus and is considered the founder of bacteriology. He worked on the isolation of infectious agents and reinfections from pure cultures, experiences from which he established the "Koch Postulates".
These postulates have been taken as a reference that describes the etiology of all the causative agents of an infectious disease, although they were originally used to describe only the tuberculosis bacillus. They are the following:
1- The agent must be present in each case of the disease and absent in the healthy.
2- The agent should not appear in other diseases.
3- The agent must be isolated in a pure culture from the lesions of the disease.
4- The agent has to cause the disease in an animal that can be inoculated
The size of the algal size will increase or swell when a student removes an algal cell from its marine environment and puts it into a sample of freshwater.
Tonicity refers to the concentration of a solution compared to another solution. A solution is said to be hypertonic, if it has a greater concentration of solutes than the other solution. A solution is said to be hypotonic, if it has a lower concentration of solutes than the other solution. A solution is said to be isotonic, if it has the same concentration of solutes as of the other solution.
In a marine environment, the algal cells are said to be hypertonic with a higher concentration of the solutes than the freshwater. When such a cell is placed in freshwater with hypotonic environment, the concentration of solutes in the cell is higher than the external environment. In other words, it has lesser water molecules in it. As a result, osmosis occurs which is the movement of water molecules from a region of its higher concentration to a region of its lower concentration through a semipermeable membrane and water enters the cell from the freshwater. Thus, increasing the size of the algal cell or the algal cell swells.
Answer:
D
Explanation:
plants make their own food not animals, hope this helped :)
Answer:
either B or D because at the end Whilst the ultimate outcome of the lytic cycle is production of new phage progeny and death of the host bacterial cell, this is a multistep process involving precise coordination of gene transcription and physical processes.
Answer:
See below
Explanation:
The difference between these two is that anabolism requires energy to grow and build and catabolism uses energy to break down.