A neuromuscular junction (or myoneural junction) is a chemical synapse formed by the contact between a motor neuron and a muscle fiber.[1] It is at the neuromuscular junction that a motor neuron is able to transmit a signal to the muscle fiber, causing muscle contraction.
Muscles require innervation to function—and even just to maintain muscle tone, avoiding atrophy. Synaptic transmission at the neuromuscular junction begins when an action potential reaches the presynaptic terminal of a motor neuron, which activates voltage-dependent calcium channels to allow calcium ions to enter the neuron. Calcium ions bind to sensor proteins (synaptotagmin) on synaptic vesicles, triggering vesicle fusion with the cell membrane and subsequent neurotransmitter release from the motor neuron into the synaptic cleft. In vertebrates, motor neurons release acetylcholine (ACh), a small molecule neurotransmitter, which diffuses across the synaptic cleft and binds to nicotinic acetylcholine receptors (nAChRs) on the cell membrane of the muscle fiber, also known as the sarcolemma. nAChRs are ionotropic receptors, meaning they serve as ligand-gated ion channels. The binding of ACh to the receptor can depolarize the muscle fiber, causing a cascade that eventually results in muscle contraction.
Neuromuscular junction diseases can be of genetic and autoimmune origin. Genetic disorders, such as Duchenne muscular dystrophy, can arise from mutated structural proteins that comprise the neuromuscular junction, whereas autoimmune diseases, such as myasthenia gravis, occur when antibodies are produced against nicotinic acetylcholine receptors on the sarcolemma.
D the amount of grass will increase, bc the deer and rabbit populations will decrease due to increased predation
<h3><u>Answer;</u></h3>
b) cycle both carbon and oxygen
<h3><u>Explanation</u>;</h3>
- Photosynthesis and cellular respiration are complementary processes by which living things obtain needed substances.
- They both consume and create the same substances (water, glucose, oxygen, and carbon dioxide) but in different ways.
- <em><u>Photosynthesis makes the glucose that is used in cellular respiration to make ATP. The glucose is then turned back into carbon dioxide, which is used in photosynthesis. </u></em>
- <em><u>While water is broken down to form oxygen during photosynthesis, in cellular respiration oxygen is combined with hydrogen to form water.</u></em>
In addition, the sum of the allele frequencies for all the alleles at the locus must be 1, so p + q = 1. ... In population genetics studies, the Hardy-Weinberg equation can be used to measure whether the observed genotype frequencies in a population differ from the frequencies predicted by the equation
Answer:
Pass information by generating electric signals
Explanation:
Neurons are the fundamental unit of the nervous system. Neurons send information across the body through generation of electric signals called as action potential. There are basically three types of neurons
a) Sensory neurons which carry information from the sense organs in the form of impulse to the central nervous system (CNS)
b) Motor neurons – These carry information from the CNS to the body parts such as sense organs, muscles etc.
c) Interneurons – They are connecting neurons which are responsible for transferring information from one neuron to the other neuron.