Unit 24- Neurological and Chemical Control Systems

The body uses both immediate and longer term controls ins maintaining homeostasis and performing its various activities. These are under chemical control by the endocrine system and neurological control by the nervous system.

This unit surveys both systems and their major modes of operation

The Endocrine System-

The endocrine system consists of 7-8 ductless glands scattered throughout the body.

Endocrine glands produce hormones that have broad controls of body metabolism.

Recall-

The endocrine system is largely controlled by the ______.

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For the most part the hormones made are either glycoproteins, steroids or smaller peptides.

Endocrine glands are ductless- they dump directly into the blood stream that is flowing around them

A diagram of the endocrine glands can be seen below

Map of the Endocrine Glands

Table of the Endocrine Hormones

Gland / Hormone / Target / Action / Controlled By
Pituitary Gland –posterior / Oxytocin
ADH- Antidiuretic Hormone
Pituitary Gland –anterior / GH- Growth Hormone
PRL- Prolactin
LH- Luteinizing Hormone
FSH- Follicle Stimulating Hormone
TSH –Thyroid Stimulating Hormone
ACTH- Adrenocorticotropic Hormone
Thyroid Gland / Thyroxine
Calcitonin
Parathyroid Glands / PTH- Parathyroid Hormone
Adrenal Gland- medulla / Epinephrine and norepinephrine
Adrenal Gland- cortex / Glucocorticoids
Mineralocorticoids
Pancreas / Insulin
Glucagon
Pineal Gland / Melatonin
Testes / Androgens-testosterone
Ovaries / Estrogens
Progesterone

The Nervous System-

The nervous system is responsible for most conscious and unconscious control of the actions of the body.

Neurons-

Anatomy of a Neuron

Neuron Function-

Overview- essentially the neuron pumps ions outside the cell membrane and sets up an ionic diffusion action potential. When gates open the flow of ions is the impulse

**The Na/K Pump is

Neuron Impulse Conduction Simplified

Typical Neuron Path

Sense organ

The Nervous System- has two main sections

  1. central nervous system-
  1. peripheral nervous system-
  1. sympathetic nerves-
  1. parasympathetic nerves-
  1. Enteric nerves-

The two parts of the system integrate at the spinal chord

Cerebrospinal Fluid-

The Reflex Arc-

Reflex-

Brain Structure and Functions

Anatomy-

4 major sections-

1. cerebrum-

2. cerebellum-

  1. brainstem-
  1. diencephalon-

Meninges-

Table Summary of Brain S & F

Region / Structure / Description / Functions
Brainstem / Pons
Medulla oblongata
Reticular formation
Cerebellum
Diencephalon / Epithalamus
Hypothalamus
Thalamus
Cerebrum / Cerebral Cortex- frontal lobe
Cerebral Cortex- parietal lobe
Cerebral Cortex- temporal lobe
Cerebral Cortex- occipital lobe
Corpus Callosum
Limbic system-amygdala, olfactory bulbs and hippocampus

Sensory Input-

The brain is able to function because we have 5 types of sensors to feed it information to work with.

Sense / Organ / location
Touch
Taste
Hearing
Smell
Vision
Heat Sense- in reptiles
Chemoreception- in reptiles
SONAR in bats and whales
Touch-Vibration in Fish
Gravity Sense- many organisms
Magnetism –in birds

Taste- chemical sensation received by the ______ on the tongue

We can distinguish the tastes of sweet, sour, biter and salty due to different sensors in the papillae- the tastes are mapped regionally on the tongue

Smell-

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Hearing –

We sense the vibration of the air as sound .

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Auditory Anatomy

Function of the Ear

Vision-

Eyes are variable in the animal kingdom

  1. ocelli-
  1. compound eye-
  1. vertebrate type single lens eye-

Anatomy of the Eye

The main sensor of the eye is a skin layer called the ______.

The retina has two types of sensory cells:

  1. rods-
  1. cones

We have an ______- defn-

Diagram of the Eye

Three Layers of the Eye’s Wall-

  1. sclera- \
  1. choroid-
  2. retina-

aqueous humor-

vitreous humor-

lens-

iris-

pupil-

Vision

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