Variation and natural selection
The correct answer is - C) carotenoids.
The majority of the trees from the mid-latitude forests tend to shade their leaves in the autumn. This process occurs because of the seasonal changes in the climate, where the trees tend to be almost not-active during the winter, so in order to preserve as much energy and nutrients as possible they get read off their leaves.
It is not a sudden process, but it takes some time, where the leaves from the initial green color start to change to yellowish, than towards orange, reddish, or brownish before they fall.
The reason why this coloration appears in the leaves when the tree starts to process of shading them off are carotenoids. The carotenoids found in the leaves, the lutein and the beta-caroten, thorugh the xantophills and the flavonoids give a yellowish color to the leaves, thus we get the beautiful autumn colors and landscapes.
Answer:
False.
Explanation:
Neurotransmitter release occurs from the nervous terminal or varicosities in the neuronal axon. When an action potential reaches the nervous terminal, the neurotransmitter is released by exocytose. The molecule binds to its receptor in the postsynaptic neuron, triggering an answer. As long as the signal molecule is in the synaptic space, it keeps linking to its receptor and causing a postsynaptic response. To stop this process the neurotransmitter must be taken out from the synaptic space. There are two mechanisms by which the neurotransmitter can be eliminated:
• Enzymatic degradation/deactivation: There are specific enzymes in the synaptic space, which are in charge of inactivating the neurotransmitter by breaking or degrading it. The enzyme acetylcholinesterase prevents ACh from continuing to stimulate contraction.
• Reuptake: Receptors located in the presynaptic membrane can capture de molecule to store it back in new vesicles for posterior use. These transporters are active transport proteins that easily recognize the neurotransmitter.
Answer:
An example that is not mentioned would be when plants give off oxygen because oxygen is vital to keep living things that require it, alive.
Explanation:
Answer:
sodium is the answer I guessed
