Answer:
The correct answer is option B ( ligand gated channels opened by neurotransmitter molecules).
Explanation:
Input region or postsynaptic region or dendrite is the site of neuron cell which receives the impulse from the pre-synaptic neuron at the synaptic junction.
The cell membrane of the dendrite is embedded with ligand-gated channels which opens up in response to the ligand (neurotransmitters) produced by the neurotransmitter vesicle of axon or output region of neuron.
The neuromuscular junction is such a case where acetylcholine receptors present in the dendrite opens in the presence of acetylcholine.
Thus, option B ( ligand-gated channels opened by neurotransmitter molecules) is the correct option.
The correct term to fill in the blank would be cortisol. In the context of stress hormones and the brain, cortisol has a profound effect on the hippocampus, a brain structure that plays a pivotal role in memory. Cortisol is classified as a steroid hormone which is produced by the adrenal gland. It is deemed as the stress hormone as it is released as a response to stress as part of the fight or flight process. From studies, cortisol was found to have effect on the hippocampus when present in high levels. It damage and kill the cells in that area of the brain. The hippocampus is the area of the brain that is responsible for the long term memory storage. So, when this part is damage then the storage for our memories would surely be affected.
<span>a. Fish have a single central heart; earthworms have several hearts.
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Multi cellular organisms are made up of billions of cells each specialized to a unique role and these cells are organized into structural and functional units such as tissues and organs.
For each cell and organ to function optimally, it requires oxygen and nutrients and needs carbon dioxide and metabolic waste taken away in a continuous, never ending process.
<span>A mechanism is needed to accomplish the important function of transporting the relevant materials to and from the cell. The circulatory system fits this bill splendidly. It is a specialized organ system which allows blood and lymph to flow through the entire body carrying nutrients such as glucose, amino acids and electrolytes as well as oxygen to each cell, at the same time carting away carbon dioxide and all sorts of metabolic waste over to excretory organs to be expelled from the body.
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Answer: B
Explanation:
If he saved the seeds and waited till summer the rays of light would make the flower red.
