STUDY SET #4 - Ch. 15 Brain & Cranial Nerves, Ch. 18 Endocrine System 💚

Central nervous system (CNS)

Consists of the brain and spinal cord

Brain

The control center of the nervous system

Major parts of the brain

Cerebrum, diencephalon, brainstem, and cerebellum

Cerebrum

Largest part of the brain responsible for perception, memory, and voluntary movement

Cerebral hemispheres

Right and left halves of the cerebrum

Longitudinal fissure

Deep groove separating the cerebral hemispheres

Gyri

Raised ridges of cerebral cortex

Sulci

Shallow grooves separating gyri

Cerebral cortex

Outer layer of gray matter of the cerebrum

White matter

Myelinated axons beneath the cortex

Lobes of the cerebrum

Frontal, parietal, temporal, occipital, and insula

Frontal lobe

Involved in voluntary motor control, planning, and personality

Parietal lobe

Involved in somatosensory perception

Temporal lobe

Involved in hearing, memory, and emotion

Occipital lobe

Primary visual processing center

Insula

Deep lobe involved in taste and visceral sensation

Primary motor cortex

Controls voluntary skeletal muscle activity

Primary somatosensory cortex

Receives sensory input from skin and muscles

Association areas

Integrate sensory and motor information

Diencephalon

Central core of brain including thalamus, hypothalamus, and epithalamus

Thalamus

Major relay station for sensory information

Hypothalamus

Regulates homeostasis, endocrine activity, and autonomic function

Epithalamus

Includes pineal gland and regulates circadian rhythms

Brainstem

Connects brain to spinal cord

Midbrain

Involved in visual and auditory reflexes

Pons

Bridge between cerebrum and cerebellum

Medulla oblongata

Controls vital functions such as breathing and heart rate

Reticular formation

Network that regulates alertness and sleep

Cerebellum

Coordinates muscle activity and balance

Arbor vitae

White matter of the cerebellum

Meninges

Protective connective tissue membranes of the CNS

Dura mater

Outer tough meningeal layer

Arachnoid mater

Middle meningeal layer

Pia mater

Inner delicate meningeal layer

Cerebrospinal fluid (CSF)

Fluid that cushions and nourishes the CNS

Ventricles

Fluid-filled cavities in the brain

Choroid plexus

Produces cerebrospinal fluid

Blood-brain barrier

Selective barrier protecting brain tissue

Cranial nerves

Twelve pairs of nerves arising from the brain

Olfactory nerve (I)

Sense of smell

Optic nerve (II)

Vision

Oculomotor nerve (III)

Eye movement and pupil constriction

Trochlear nerve (IV)

Eye movement

Trigeminal nerve (V)

Facial sensation and chewing

Abducens nerve (VI)

Eye movement

Facial nerve (VII)

Facial expression and taste

Vestibulocochlear nerve (VIII)

Hearing and balance

Glossopharyngeal nerve (IX)

Taste and swallowing

Vagus nerve (X)

Parasympathetic control of viscera

Accessory nerve (XI)

Neck and shoulder movement

Hypoglossal nerve (XII)

Tongue movement

Endocrine system

System of glands that secrete hormones into the bloodstream

Hormones

Chemical messengers that affect distant target cells

Endocrine glands

Ductless glands that secrete hormones internally

Neuroendocrine cells

Cells that release hormones in response to neural signals

Hypothalamus

Link between nervous and endocrine systems

Pituitary gland

Master gland that regulates other endocrine glands

Adenohypophysis

Anterior pituitary glandular tissue

Neurohypophysis

Posterior pituitary nervous tissue

Hypophysial portal system

Vascular connection between hypothalamus and anterior pituitary

Anterior pituitary hormones

GH, TSH, ACTH, FSH, LH, PRL

Growth hormone (GH)

Stimulates tissue growth and metabolism

Thyroid-stimulating hormone (TSH)

Stimulates thyroid hormone release

Adrenocorticotropic hormone (ACTH)

Stimulates adrenal cortex

Follicle-stimulating hormone (FSH)

Stimulates gamete production

Luteinizing hormone (LH)

Stimulates ovulation and testosterone secretion

Prolactin (PRL)

Stimulates milk production

Posterior pituitary hormones

ADH and oxytocin

Antidiuretic hormone (ADH)

Promotes water retention by kidneys

Oxytocin

Stimulates uterine contractions and milk ejection

Pineal gland

Secretes melatonin

Melatonin

Regulates circadian rhythms

Thyroid gland

Regulates metabolic rate

Thyroxine (T4)

Primary thyroid hormone

Triiodothyronine (T3)

More active thyroid hormone

Calcitonin

Lowers blood calcium levels

Parathyroid glands

Regulate calcium homeostasis

Parathyroid hormone (PTH)

Raises blood calcium levels

Adrenal glands

Sit atop kidneys

Adrenal medulla

Secretes epinephrine and norepinephrine

Adrenal cortex

Secretes corticosteroids

Mineralocorticoids

Regulate electrolyte balance

Glucocorticoids

Regulate metabolism and stress response

Pancreatic islets

Endocrine portion of pancreas

Insulin

Lowers blood glucose

Glucagon

Raises blood glucose

Gonads

Testes and ovaries

Testosterone

Primary male sex hormone

Estrogen

Primary female sex hormone

Progesterone

Maintains pregnancy

Endocrine cells of other organs

Hormone-secreting cells in heart, kidneys, GI tract, and adipose tissue