Answer:
1) Accommodation is the process of changing the shape of the lens to focus on near or distant objects.
- <em>To focus on a near object</em> – the lens becomes thicker, this allows the light rays to refract (bend) more strongly.
- <em>To focus on a distant object </em>– the lens is pulled thin, this allows the light rays to refract slightly.
2) - i don't know. im so sorry -
Answer:
Answered below.
Explanation:
The nerve fibres of the autonomic nervous system that connects the ganglia to the the central nervous system are called preganglionic fibres. They are divided into sympathetic preganglionic fibres and parasympathetic preganglionic fibres and both have acetylcholine as their neurotransmitter.
The sympathetic preganglionic is shorter compared to the parasympathetic preganglionic fibres. They originate from the hypothalamus and brainstem and project to the ganglia non the spinal cord. A ganglion is a cluster of nerves outside the central nervous system.
The preganglionic sympathetic fibres originating from T1-T2 innervate the cervical ganglion which innervates the muscles of the pupils (dilators).
The postganglionic fibres originating from the preganglionic fibres of T11-L3 passes through splenic, celiac and mesenteric ganglia to innervate the kidneys and renal vessels.
