a&p test 4

Sympathetic nervous system commonly used ______ as preganglionic neurotransmitter and ______ as postganglionic neurotransmitter.

ACH, NE

Major parts of the brain?

Cerebellum, cerebrum, diencephalon, brain stem.

8. List the structures, in proper order, through which the light passes into the eye.

Cornea, aqueous humor, pupil, lens, vitreous humor, photo receptors backed by the retina.

12. Which structure allows left and right hemispheres to "talk" to each other?

Corpus callosum

6. Which structure is considered the command and control center for the endocrine system and the ANS?

Diencephalon

What is the most superficial covering of the spinal cord( right under the bone of vertebra)?

Dura mater

Which structure of the brain is responsible for state of wakefulness and alertness?

Midbrain

7. Explain the function of melatonin and indicate where it is made.

More melatonin is secreted in darkness so it promotes sleepiness and helps regulate our biological clocks. It is made in the pineal gland.

1. What is the role of cervical and lumbar enlargements in the spinal cord?

Motor neurons for limbs

Main function of cerebellum

(Motor control) Regulates posture, equilibrium, and balance.

17. Name the regions of the ear and briefly describe their anatomy.

1) External ear-collects sounds waves and channels then inward 2) Middle ear-conveys sound vibrations to the oval window 3) Internal ear-houses the receptors for hearing and equilibrium

3. Name 4 major regions of adult brain and briefly describe their function.

1. Brainstem- continuous of the spinal cord and consists of medulla, oblongata, pons, and midbrain. 2. Cerebellum- posterior to the brain 3. Diencephalon- superior to the brain 4. Cerebrum- the largest part of the brain, supported on the diencephalon and brain stem

5. What 3 structures make up brain stem? Briefly describe the function of each.

1. Medulla oblongata - • connects the brain to the spinal cord • respiration • cardiovascular center • Vomiting, coughing, and sneezing centers. 2. Pons - it acts as a bridge connecting the spinal cord with the brain an parts of the brain with each other. motor control and sensory analysis. • Helps to control breathing 3. Midbrain- connects pons to diencephalon. • Contains peduncles(little feet) that have axons of the tracts which conduct nerve impulses to the spinal cord, medulla, and pons.

16. What causes glaucoma and what are the symptoms?

A buildup of aqueous humor within the anterior cavity which can be from previous injury, disorder, increasing age, family history, race (African American). Symptom: retinal damage and loss of vision

12. What happens during macular degeneration and what are the symptoms?

A degenerative disorder of the retina in persons 50 years of age and older. Lose of the ability to see straight ahead happens. Symptoms: blurring, distortion at the center of the visual field

22. What is the function of otoliths and where are they located?

A layer of dense calcium carbonate crystals, that extends over the otolithic membrane. They maintain static equilibrium

10. Define what a dermatome is. How can they be used for diagnostics in neurology?

Areas of the skin that provide input through one pair of spinal nerves. Dermatome maps are used for diagnostic of spinal nerve and spinal cord injuries.

3. What else besides axons is present in a nerve?

Associated connective tissue and blood vessels

17. Explain what an "autonomic tone" is. Give examples of organs that have "sympathetic tone" or "parasympathetic tone".

Autonomic tone is allows control of organ both ways with just one division; either sympathetic or parasympathetic Sympathetic tone has blood vessels smooth muscle Parasympathetic tone has cardiac muscle

13. What are the pyramids of the medulla, and what is the result of their "decussation"?

Axons from the left pyramid cross over to the right and axons on the right cross over to the left ( decussation of pyramids)-that the left hemisphere of the brain controls the right side muscles and the right hemisphere controls the left side

16. Medulla oblongata, pons and midbrain make up what structure?

Brain stem

Medulla oblongata, pons, and midbrain are part of...

Brain stem

Which region controls rhythmic breathing, blood pressure and heart rate.

Brain stem

33. Which areas of cerebral cortex are responsible for speaking and for speech understanding?

Broca's speech area

23. Which cranial nerves (name and number) conduct the sensation of smell, vision, hearing and taste?

CN I sense of smell CN II sense of sight CN III, IV, VI innervates the extraocular muscles that allow us to move our eyes. CN III supplies motor input to our eyelid muscles and facilitates pupil constriction. CN V the major sensory nerve of the face. Supplies the ophthalmic, maxillary, and mandible. CNVIII facial expressions and taste CN VIII hearing CN IX taste CN X carries most of the parasympathetic motor efferents to the organs of the thorax and abdomen. CN XI supplies somatic innervation to the trapezius and sternocleidomastoid muscles. CN XII chew, talk , and swallow

4. Name locations of the brain ventricles

CSF (cerebrospinal fluid) - a clear colorless fluid composed primarily of water that protects the brain and spinal cord from chemical and physical injuries. • Floats the brain-makes it lighter • Cushioning-prevents concussions • Chemical exchange-transports nutrients and wastes 1. Lateral ventricles- in each hemisphere of the cerebrum (ventricle 1 and 2) 2. Third ventricle- narrow slitlike cavity along the midline superior to the hypothalamus 3. Fourth ventricle- lies between the brain stem and the cerebellum.

11. Describe the location of spinal sensory and motor neurons (somatic and autonomic).

Each somatic motor neuron has a threadlike axon that extends from the brain or spinal cord to a group of skeletal muscle fibers. The autonomic nervous system is a control system that acts largely unconsciously and regulates bodily functions such as the heart rate, digestion, respiratory rate, pupillary response, urination, and sexual arousal

18. Give example of dual (sympathetic/parasympathetic) innervation of organs and describe its effects.

Eyes- pupil dilation/ constriction Glands- nasal,lacrimal,salivary, GI- decrease /increase secretion

1. List the cerebral meninges in order from superficial to deep.

Function: protective connective tissue that encircle the spinal cord and brain. Dura mater-thick strong layer composed of dense irregular connective tissue. Arachnoid mater-thin layer of delicate collagen fibers and some elastic fibers. Between dura mater and arachnoid mater is a thin subdural space that contains interstitial fluid. Pia mater-thin transparent connective tissue that contains denticulate ligaments for the thickening of the pia mater and protect spinal cord against sudden displacement. Between the arachnoid and the pia mater is a space called subarachnoid space which contains shock absorbing cerebrospinal fluid.

20. What is the main function of thalamus?

Functions as a relay station for all sensory impulses to the cerebral cortex. Ex; pain, temp, touch, pressure

25. What is function of reticular formation? Which hormones/drugs have an effect on it?

Functions to maintain consciousness, a state of wakefulness in which an individual is fully alert, aware, and oriented.

4. Give examples of mechanoreceptors, chemoreceptors and photoreceptors.

Mechanoreceptors provide sensations of touch, pressure, vibration, proprioception, and hearing, and equilibrium. Also monitor stretching of blood vessels and internal organs. Chemoreceptors detect chemicals in mouth (taste), nose (smell), and body fluids. Photoreceptors- detect light that strikes the retina of the eye.

2. PNS consists of nerves and what other structures?

Ganglia, enteric plexuses, and sensory receptors

2. Describe histological differences between white and gray matter. Where is each one located in the brain?

Gray matter is made of neuronal cell bodies, unmyelinated axons, axon terminals, and neuroglia. Found; in the brain, brainstem, cerebellum, and spinal cord. White matter-myelinated axons. The white matter surround the gray matter. made up of fibers.

9. List lobes and fissures of cerebral hemispheres

Hemispheres are separated by the deepest sulcus called longitudinal fissure. Transverse fissure is between cerebellum and cerebrum. Temporal lobe, occipital lobe, parietal lobe , frontal lobe.

19. How does the ear distinguish the sounds of different pitch?

High frequency ( high pitched) sounds induce maximal vibration in the base of the cochlea because the membrane is narrower and stiffer at the base of the cochlea. Low frequency ( low-pitched) sounds cause maximal vibration of the basilar membrane there.

32. Which structure of the brain plays the main role in long-term memory formation?

Hippocampus

20. Which structures are responsible for static equilibrium? Describe their function.

In vestibule bony chamber between semicircular canals and cochlea.

Constrictiom of the arteries is caused by

Increase of sympathetic stimulation

Which of the following is not true about parasympathetic nervous system?

Is assisted by hormones from adrenal glands Most active when you are relaxing on a couch Decreases heart rate and blood pressure Long preganglionic and short postganglionic fibers Increases digestive system activity

11. Why is the "blind spot" of the eye blind? Explain its anatomical structure.

It does not contain rods or cones. The blind spot on the surface of the retina, located about 3 mm to the nasal side of the macula. It is the point where the fibers of the retina leave the eye and become part of the optic nerve. It is only the part of the retina that is insensitive to light.

11. Where is primary motor cortex located and what is its function?

It is located in the precentral gyrus of the frontal lobe. Various regions of the cerebral cortex are involved in planning of the voluntary motor functions in the human body.

27. What are the functions of limbic system?

It plays a primary role in promoting a range of emotions, including pleasure, pain, docility, affection, fear, and anger and memory

18. What is the name of an area that allows a person to understand spoken words?

Left hemisphere of cerebral(brochas area)

8. What is the main function of CSF and where can it be found?

Mechanical protection-serves as a shock absorbing medium that protects the delicate tissue of the brain and spinal cord. Homeostatic function- maintains homeostatic controls for brain tissue. Circulation- CSF is a medium for minor exchange of nutrients and waste products between the blood and adjacent nervous tissue. It can be found- the subarachnoid space (the space between the arachnoid mater and the pia mater) and the ventricular system around and inside the brain and spinal cord.

14. In which region of the brain stem do we have reflex centers for coughing and sneezing?

Medulla oblongata

3. Which receptors sense pain? What is the structure of a pain receptor?

Nociceptors sense pain.

24. Which regions of the cortex are involved in processing information from vision and hearing?

Occipital lobe (vision) and temporal lobe( hearing)

29. Which cranial nerves are involved in 5 major senses?

Olfactory ,optic, oculomotor, trochlear, trigeminal, abducens ,facial, vestibulochochlear, glossopharyngeal ,vagus, accessory hypoglossal

9. Name the conditions that result from spinal cord injuries.

Paraplegia Hemiplegia quadriplegia

5. Explain which reflexes can be used for medical diagnostics.

Patellar reflex- it is extension of leg at the knee joint by contraction of the quadriceps femoris muscle in response to tapping the patellar ligament. It the leg does not extend, then the sensory or motor neuron are damaged. Achilles reflex- plantar flexion of the foot by contraction of the gastrocnemius and soleus muscles in response to tapping the calcaneal Achilles tendon. No response means damage to nerve supplying the posterior leg muscles or to neurons in the lumbosacral region of the spinal cord. Babinski sign- gentle strokes of the lateral outer margin of the sole. If not responding, incomplete myelination of fibers in the corticospinal tract. Abdominal reflex- contraction of the muscles that compress the abdominal wall in response to stroking the side the abdomen side. If absent, it is associated with lesions of the corticospinal tract.

15. Name the light-sensitive protein that is present in rods and cones.

Photopigments proteins

24. How does the blood-brain barrier work?

Prevents toxins from harming brain.

34. List the phases of sleep and briefly describe each one. When do we have dreams?

REM - "rapid eye movement" phase, all muscles relaxed, very deep sleep - dreams happen during REM sleep NREM - deep sleep We have dreams during REM sleep.

17. Destruction of which system of the brain would most likely result in an irreversible coma?

Reticular formation

13. What is the difference between rods and cones of the retina in terms of their light sensitivity and color perception?

Rods; Contain more photo pigments High sensitivy due to the greater number of disks and higher pigment concentration Under low light conditions, only rods contribute to vision and they do not mediate color vision. Achromatic-without color Cones; Are the cells capable of color vision and responsible for high spatial acuity. Lower absolute sensitivity Chromatic-color vision

7. Are ascending tracts of the spinal cord motor or sensory?

Sensory

4. Name 5 components of a reflex arc.

Sensory receptor Sensory neuron Integrating center Motor neuron effector

ANS controls all of the following

Smooth muscle Cardiac muscle Glands(salivary, sweat, adrenals,etc.) Endocrine Exocrine

15. What is the difference between somatic reflex and autonomic reflex? Give an example of each reflex.

Somatic reflex is the contraction of the skeletal muscles Example is when you quickly pull your hand away from a hot object autonomic reflex is involvment of response of smooth muscle, cardiac muscle, and glands. Example is your heart beat

1.what is the difference between somatensions and special senses?

Special senses are sensory modalities of smell, taste, vision, hearing, and equilibrium or balance. A somatosensory sensation; the perception of sensory stimuli coming from the skin that involves senses of touch, temperature, body position, and pain.

6. What is cauda equina made of?

Spinal nerves in lumbar and sacral region

Cauda equina is mostly composed of

Spinal nerves in lumbar and sacral region

Where is cerebrospinal fluid CSF found?

Subarachnoid space

36. Which regions of the brain are damaged in Parkinson's disease? What is their normal function?

Subsantia nigra to the putamen and caudate. Subsantia nigra functions: Controls Voluntary Movement Produces the Neurotransmitter Dopamine Regulates Mood Putamen functions: regulate movements and influence various types of learning. Caudate functions: it uses information from past experiences to influence future actions and decisions.

35. Describe the roles of superior and inferior colliculi. In which part of brain are they located?

Superior colliculi: responsible for reflexes that govern movements of the head, eyes, and trunk in response to visual stimuli. Inferior colliculi: relays impulses from the receptors for hearing in the inner ear to the brain. They are both located in the tectum(posterior part of midbrain).

5. Name all the muscles that are associated with eye function, explain what each does and indicate whether it is a skeletal or a smooth muscle.

Superior rectus- move the eyeballs superiorly and inferiorly Inferior rectus-move the eyeballs superiorly and inferiorly Lateral rectus-move the eyeballs laterally and medially Medial rectus-move the eyeballs laterally and medially Superior oblique- moves the eyeballs inferiorly and laterally Inferior oblique-moves the eyeballs superiorly and laterally Ciliary muscle-smooth muscle, alters the shape of lens, adapting for near and far vision. Pupillary muscle- turns bigger dim light and smaller when there is bright light.

31. Which senses are called "somatic senses" and where in the brain is the information for somatic senses processed?

Tactile sensations Somatosensory system

6. What is the function of tears and which glands produce them?

Tears protects, cleans, lubricates, and moistens the eyeball. The lacrimal glands produce the tears.

7. Fibrous tunic of the eye forms which two structures? Which structure regulates the amount of light, entering the pupil?

The anterior cornea and posterior sclera. Iris regulates the amount of light, entering the pupil.

22. What is lateralization of cerebral hemispheres?

The brain has left and right brain. The left hemisphere is more important for reasoning, numerical and scientific skills, spoken and written language, and the ability to use and understand sign language. The right hemisphere is more specialized for musical and artistic awareness; spatial and pattern perception; recognition of faces and emotional content of language; discrimination of different smells; and generating mental images of sight, sound, touch, and taste.

10. Which anatomical landmark separates primary motor cortex from somatosesnory cortex?

The central sulcus

21. List the functions of the cerebellum.

The cerebellum compares movements with skeletal muscles, regulates posture, equilibrium, and balance. It also plays a role in motor memory, spatial orientation, and language processing.

which eye structure regulates the amount of light entering the pupil

iris

20. Which division of ANS has: pre-vertebral ganglia? Long pre-ganglionic and short post-ganglionic neuron?

The sympathetic ganglia has pre-vertebral ganglia. The parasympathetic division has long preganglionic and short post ganglionic neuron

8. What is the structure of pain receptors?

They have nociceptors which are free nerve endings in every body tissue except brain.

2. What are visceral sensations? Give examples.

They provide information about conditions within internal organs, for example, pressure, stretch, chemicals, nausea, hunger, and temperature.

23. When you have a toothache, which cranial nerve conducts the main sensations?

Trigeminal nerve

which cranial nerve innervated the inner ear?

VIII=8

15. What brain structure looks like a worm in where is it located?

Vermis of cerebellum

14. Describe the function of autonomic ganglia. Where are sympathetic and parasympathetic ganglia located?

clusters of neuron cell bodies that transmit sensory signals from the periphery to integration centers in the CNS. Sympathetic ganglia is located in the sympathetic division of the ANS located just ventral and lateral to the spinal cord. Parasympathetic ganglia is located in the parasympathetic division of the ANS located in two sites within the central nervous system (CNS)

9. Why is it important for lens of the eye to change shape? What happens when the lens becomes less elastic?

When the lens is convex, it will refract incoming light rays toward each other so that they intersect. When the lens curves inward, like the inside of a hollow ball, the lens is said to be concave and causes light rays to refract away from each other. When the eye is focusing on a close object, the lens becomes more curved, causing greater refraction of the light rays. Farsightedness occurs when the lens becomes less elastic.

what is true about the fibrous tunic of the eye?

it consists of transparent cornea and white sclera

19. What system is called an "emotional brain"?

limbic system

30. In which parts of the cortex are the primary fields for visual and for auditory processing?.

primary visual area- is located at the posterior tip of the occipital lobe mainly on the medial surface primary auditory area- is in the superior part of the temporal lobe

the primary auditory fields are located in which part of the brain?

temporal lobe

what is correct about cones

they allow color vision

otoliths(calcium carbonate crystals in gel) may be normally found in the

vestibule

14. Which vitamin is essential for vision and how does it help?

vitamin A, it helps by creating rhodospin which helps in night vision. Vitamin A deficiency causes blindness.

19. Name the division of ANS that:

• increases digestive activity-parasympathetic • speeds up heart rate-sympathetic • dilates bronchioles-sympathetic • causes erection of the penis-parasympathetic • causes pupil constriction-parasympathetic

10. Describe the following structures:

• optic disc-is the site where the optic nerve(II) exits the eyeball. • macula lutea- is in the exact center of the posterior portion of the retina, at the visual axis of the eye. • fovea centralis- a small depression in the center of the macula lutea, contains only cones.