The correct answer is option d, that is, neurotransmitters.
A neurotransmitter refers to a chemical component, which is discharged at the terminal of a nerve fiber by the introduction of a nerve impulse, and by diffusing across the junction or synapse. It helps in the transfer of the impulse to another muscle fiber, nerve fiber, or some other composition. Acetylcholine is a kind of neurotransmitter, that is, used by neurons in the CNS and the PNS in the control of activities ranging from heart rate and muscle contraction to digestion and memory.
They are things your body cannot produce on it's own
Answer: the two tropics zones
Explanation:
Between the two tropics zones, which includes the equator, the Sun is directly overhead twice per year. Outside the tropic zones, whether to the south or north, the Sun is never directly overhead. Two other significant lines of latitude are the Arctic Circle (around the North Pole) and the Antarctic Circle (around the South Pole).
A bacterial infection of the periodontium that causes rapid attatchment loss and poor response to periodontal therapy has a grade of Aggressive periodontal disease
<h3>Periodontium </h3>
The cementum, gingiva, periodontal ligament (PDL), and alveolar bone make up the complex structure known as the periodontium. The periodontium's main purposes are to protect the underlying structures of the tooth from the oral microflora and to enable the tooth to connect to the bone.
An orthokeratinized or parakeratinized stratified squamous epithelium makes up the gingival epithelium. The gingiva, which has connective tissue and epithelial components, covers the supracrestal root surface and the alveolar bone. As it lines the gingival sulcus close to the tooth surface (enamel or cementum) and subsequently joins to it with hemidesmosomes, the gingival (oral) epithelium develops into the sulcular epithelium and junctional epithelium.
Learn more about periodontium here:
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<span>The cell that does not have a cell wall is the <em>"animal cell".
</em>Have a wonderful day! :D<em>
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