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
Facilitated diffusion is the diffusion of solutes through transport proteins in the plasma membrane. Facilitated diffusion is a type of passive transport. Even though facilitated diffusion involves transport proteins, it is still passive transport because the solute is moving down the concentration gradient.
Answer:
Option B
Explanation:
In biology, fitness refers to the ability of an organism to survive, reproduce, mate and support evolution through gene transfer. A fitness of 0.28 signifies that only 28 percent of a given population are fit physically and able to reproduce while the remaining 72 % are unable to mate and hence cannot reproduce and contribute towards gene flow and evolution.
Hence, option B is correct
Answer:
naturalistic observation
Explanation:
The best possible way to study how tigers interact with each other in their habitats would be to use a naturalistic observation. This type of observation focuses on observing the main subject of the study in it's natural environment without interfering in any sort of way. This allows the scientists to observe exactly how the tigers interact when there are no humans around.
Ensory cells<span> are </span>cells<span> which detect information (such as sounds, light, touch, smell, taste, and temperature) through receptors on their surface. This information travels through nerves from the </span>sensory cells<span> to the brain.</span>