Answer:
B
Explanation:
The Ames test is a bacteriological technique commonly used to determine if a particular chemical or substance can cause mutations. To achieve this, researchers use bacteria (commonly <em>Salmonella typhimurium</em>) as this bacteria strain is unable to grow in a medium that does not contain histidine (a very important amino acid in the biosynthesis of proteins). If the studied substance is able to cause mutations, bacteria will mutate, and they will be able to grow on that particular media even if they don’t have histidine for their metabolism. Therefore, if there are colonies growing, the chemical being tested is mutagenic.
I hope this clarify your inquiry.
Answer: She called it a rhizome because a rhizome has nodes and inter nodes and is a modified stem that helps in propagation of the plant.
Explanation:
The roots of irises plant is called as rhizome because it has nodes and inter nodes. They have the ability to run inside the ground in a horizontal way.
As it is a stem it contains nodes and inter nodes in it. The nodes of the stem contains the axillary buds.
It is different from normal roots in the respect that normal roots does not contains nodes and inter nodes.
Answer: A.
Explanation:
The secondary growth of a plant happens in the vascular cambium. When the vascular cambium produces more tissues, it makes the stems thicker over time.
Answer:
pulse
axon
action potential
frontal lobe
hypothalamus
occipital
dopamine
Before receiving a nerve impulse, a neuron is at its resting potential, with more negative charges inside the cell than on the outside of the cell. When the neuron receives the nerve impulse, it is depolarized, allowing positive ions to flow across the cell membrane into the neuron. This is called an action potential, and the action potential travels the length of the neuron, taking advantage of the myelin sheath on many neurons. Once the signal has traveled through the neuron, the sodium-potassium pump repolarizes the cell, restoring the resting potential of the neuron.
Explanation:
The correct answers are 1, 2 and 4
