It's a system of chronological dating and geologists use it to describe the timing and relationships of events in Earth's history
The term "IMViC" is an acronym for each of these tests. "I" is for indole test; "M" is for methyl red test; "V" is for Voges-Proskauer test, and "C" is for citrate test. The lower case "i" is merely for "in" as the Citrate test requires coliform samples to be placed "in Citrate". Triple sugar iron test (TSI), Urease Test and Malonate Test are also included in this test.
For each of the tests, different reagents are added to the species are inoculated and tested.
For Salmonella sp. the IMViC Test result is:
Indole - negative
Methyl red - Positive
Voges-Proskauer - negative
Citrate - positive
Option A. Increases and decreases of the heart rate result from changes in the activity of the <u>medulla oblongata</u>
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What is medulla oblongata ?
- Medulla oblongata, also called medulla, the lowest part of the brain and the lowest portion of the brainstem.
- The medulla oblongata is connected by the pons to the midbrain and is continuous posteriorly with the spinal cord, with which it merges at the opening (foramen magnum) at the base of the skull.
- The medulla oblongata plays a critical role in transmitting signals between the spinal cord and the higher parts of the brain and in controlling autonomic activities, such as heartbeat and respiration
- The medulla is divided into two main parts: the ventral medulla (the frontal portion) and the dorsal medulla (the rear portion; also known as the tegmentum).
- The ventral medulla contains a pair of triangular structures called pyramids, within which lie the pyramidal tracts.
- The pyramidal tracts are made up of the corticospinal tract (running from the cerebral cortex to the spinal cord) and the corticobulbar tract (running from the motor cortex of the frontal lobe to the cranial nerves in the brainstem)
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