6.18.F - Exam: Quarter Two review

Neuroglial cells (also referred to as glial cells or simply neuroglia) are the "support cells" of the nervous system. These cells are unlike the neuron in that they DO NOT conduct electrical impulses. There are six different types of glial cells in the nervous system. Two of the six are found in the Peripheral Nervous System (PNS), while the other four are in the Central Nervous System (CNS). Neuroglial Cells of CNS The four types of glial cells in the CNS are astrocytes, microglial cells (or microglia), ependymal cells, and oligodendrocytes. The glial cells are more abundant than the neurons within the nervous system, and they each have specialized functions.

-"Astro" refers to "star," and these cells are called astrocytes because their shape resembles that of a star, as seen in the green cell in the image below. The long, branched extensions of the astrocyte can wrap around nearby structures within the brain, including small capillaries. In fact, the portion of the astrocyte that wraps around the capillaries in the brain help to form the blood-brain barrier. This barrier acts as a protective layer around the blood vessels in the brain, preventing harmful chemicals from damaging the delicate nervous tissue in the brain. Astrocytes also help to regulate the chemical environment of the nervous tissue within the brain. -Microglial cells are a type of phagocytic cell, meaning that they can engulf debris and wastes within the nervous tissue of the brain and spinal cord. -Ependymal cells form an epithelial lining within the brain and spinal cord. They line the central canal of the spinal cord and also line large cavities in the brain called ventricles. One of their jobs at the ventricles is that they assist in the production of cerebrospinal fluid (CSF). -Oligodendrocytes, like astrocytes, also have cellular processes. However, their cellular processes wrap around axons within the brain and spinal cord, helping form the myelin sheath.

Intermediate Flexors Flexor digitorum superficialis m. is the only muscle in the intermediate layer of the forearm flexors. -FLEXOR DIGITORUM SUPERFICIALIS M. The only intermediate layer in the forearm flexors is the flexor digitorum superficialis m. The layer can be found underneath the pronator teres m., flexor carpi radialis m., palmaris longus m., and the flexor carpi ulnaris m. Origin: Humerus (medial elbow) Insertion: Fingers 2-5 Action: Flexes fingers and wrists Deep Flexors Three muscles make up the deep flexors: flexor digitorum profundus m., flexor pollicis longus m., and the pronator quadratus m. -The deep flexor muscle to the digits is the flexor digitorum profundus m. It lies adjacent to the flexor pollicis longus m. Origin: Ulna Insertion: Fingers 2-5 Action: Flexes hand and flexes fingers

-A square-shaped muscle, hence the inclusion of the term "quad," lies across the wrist. This is the pronator quadratus m. Origin: Ulna Insertion: Radius Action: Pronates hand -Next to the flexor digitorum profundus m. is the flexor pollicis longus m. "Pollex" is the Latin word for thumb. Origin: Radius Insertion: Thumb Action: Flexes thumb Superficial Extensors The superficial extensors are on the posterior side of the forearm and include the brachioradialis m., extensor carpi radialis longus m., extensor carpi radialis brevis m., extensor digitorum m., extensor digiti minimi m., and extensor carpi ulnaris m.

Five muscles in the adductor group are responsible for the adduction of the thigh, with some of the muscles having additional functions. -The pectineus muscle is a large flat muscle found in the thigh. Origin: Pelvis Insertion: Femur Actions: Adducts and flexes the thigh -Adductor brevis m. is a short muscle that adducts the thigh. Origin: Pelvis Insertion: Femur Actions: Adducts thigh -The adductor longus m. is a large, flat muscle that covers the adductor brevis m. and adductor magnus m. Origin: Pelvis Insertion: Femur Actions: Adducts thigh

-Adductor magnus m. is the largest and most posterior of the adductor muscles. Origin: Pelvis Insertion: Femur Actions: Adducts and extends thigh -Gracilis m. is the most superficial and medial of the adductor group muscles. Crossing both the hip and knee joints, it can induce movement at both the hip and knee. Origin: Pelvis Insertion: Tibia Actions: Adducts thigh and flexes leg

The action for muscle C. Flexes big toe and plantar flexes the foot Extends big toe and plantar flexes the foot Extends big toe and dorsiflexes the foot Flexes big toe and dorsiflexes the foot

-Extends big toe and dorsiflexes the foot

What is the action of the muscle at C? Extends fingers 2-5 Flexes finger 5 Extends finger 5 Flexes fingers 2-5

-Extends finger 5

The muscle at B. Extensor hallucis longus m. Tibialis anterior m. Extensor digitorum longus m. Gastrocnemius m.

-Extensor digitorum longus m.

The muscle at C. Gastrocnemius m. Extensor digitorum longus m. Tibialis anterior m. Extensor hallucis longus m.

-Extensor hallucis longus m.

Which muscle is shown at A? Internal intercostal mm. Pectoralis major m. Pectoralis minor m. External intercostal mm.

-External intercostal mm.

Check all that apply. These muscles can be clearly seen in this image. External oblique mm. External intercostal mm. Rectus abdominis m. Diaphragm m.

-External oblique mm. -Rectus abdominis m.

Which muscle is labeled B? Fibularis brevis m. Extensor digitorum longus m. Tibialis anterior m. Fibularis longus m.

-Fibularis brevis m.

Check all that apply. Which muscles can be clearly seen in this image? Internal intercostal mm. Diaphragm m. External oblique m. Rectus abdominis m.

-Internal intercostal mm.

Which muscle is shown at B? External intercostal mm. Pectoralis minor m. Internal intercostal mm. Pectoralis major m.

-Internal intercostal mm.

Check all that apply. Which muscles are more superficial than C? Internal oblique m. External oblique m. Transversus abdominis m.

-Internal oblique m. -External oblique m.

Which muscle is at letter M?

-Levator scapulae m.

Check all that apply. These bones are part of the 14 facial bones. Occipital Bone Mandible Bone Parietal Bone Vomer

-Mandible Bone -Vomer

Check all that apply. These are all types of neuroglia within the CNS. atellite cell Microglial cells Ependymal cells Oligodendrocyte Schwann cell Astrocyte

-Microglial cells -Ependymal cells -Oligodendrocyte -Astrocyte

Muscles of the Upper Arm Muscles that control the movement in the upper arm are located in the chest and the back. Usually, these muscles are the most superficial muscles in the chest and back. Pectoralis Group An example of those muscles that move the arm (and not actually located in the arm) is the pectoralis muscles. Anterior and superficial to the intercostal muscles are the pectoral muscles, which are located on the chest and move the upper limb.' The pectoralis group moves the upper arm and includes the most superficial chest muscles: pectoralis major m., pectoralis minor m., and the serratus anterior m.

-On the lateral side of the chest wall is the serratus anterior m. Origin: Ribs Insertion: Scapula Action: Protracts scapula -A fan-shaped muscle on the chest, the pectoralis major m. has various points of origin. Origin: Clavicle, sternum, and ribs Insertion: Humerus Action: Flexes, adducts, medially rotates arm -A smaller muscle lying beneath the pectoralis major m is the pectoralis minor m. Origin: Ribs Insertion: Scapula Action: Elevates ribs, protracts scapula The deltoid group includes the deltoideus m. and teres minor m. Both of these muscles laterally rotate the humerus. -The deltoideus muscle is the prominent shoulder muscle and is responsible for various arm movements. Origin: Scapula and clavicle Insertion: Humerus Action: Abducts, flexes, extends, medially and laterally rotates humerus -A small portion of teres minor m. can be seen superior to the teres major m. and inferior to the larger infraspinatus m. It tucks underneath the deltoideus m. into a portion of the humerus called the posterior greater tubercle. Origin: Scapula Insertion: Humerus Action: Laterally rotates the humerus

The muscle at E. Pronator quadratus m. Flexor pollicis longus m. Pronator teres m. Flexor digitorum profundus m.

-Pronator quadratus m.

Which muscle is located at A? Flexor digitorum superficialis m. Pronator teres m. Brachioradialis m. Palmaris longus m.

-Pronator teres m.

Wrist and Finger Flexors Superficial Flexors On the anterior/palmar side of the forearm are the superficial flexors. Before trying to label muscles, mentally orient yourself and ask yourself these questions. Where is the ulna (pinky side)? Where is the radius (thumb side)? Is this the anterior side, or is it the posterior side of the forearm? Study the origin, insertion, and action of the muscles of the anterior side of the left forearm in the images below. PRONATOR TERES M.FLEXOR CARPI RADIALIS M.PALMARIS LONGUS M.FLEXO

-Pronator teres m. is a rectangular muscle located in the superficial region of the anterior compartment. Origin: Humerus (medial elbow) Insertion: Mid-region of radius Action: Pronates hand -The flexor carpi radialis m. is a long muscle that runs from the medial elbow to the radius side of the forearm. Origin: Humerus (medial elbow) Insertion: Base of metacarpals 2 and 3 Action: Flexes and abducts hand -The palmaris longus m. runs from the elbow and passes through the wrist. Origin: Humerus (medial elbow) Insertion: Base of hand Action: Flexes hand -The flexor carpi ulnaris m. is a long muscle that runs from the medial elbow to the ulna side of the forearm. Origin: Humerus (medial elbow) Insertion: Wrist Action: Flexes and adducts hand

Check all that apply. Which muscles are visible in this image?

-Psoas major m. -Iliacus m.

Check all that apply. These are the neuroglia of the PNS. Schwann cells Microglial cells Astrocytes Satellite cells Ependymal cells

-Satellite cells -Schwann cells

Check all that apply. These are the broad functions of the nervous system. Sensory input Muscle contraction Motor response Information processing Hormone release

-Sensory input -Motor response -Information processing

Check all that apply. These are the components of the nervous system. Brain Spinal cord Smooth muscle Nerves

-Spinal cord -Brain -Nerves

Brachial Group The brachial group consists of the coracobrachialis m., brachialis m., and the biceps brachii m, which are on the anterior side of the arm. This group of muscles is in the area that is commonly known collectively as the biceps. -The muscle you see when you "flex the arm" is the biceps brachii m. Origin: Humerus Insertion: Radius Action: Flexes forearm; supinates hand -Deep to the biceps brachii m. is the brachialis m. It also flexes the forearm. Origin: Humerus Insertion: Ulna Action: Flexes forearm Triceps Brachii On the posterior side of the upper limb is the triceps brachii m.

-TRICEPS BRACHII M. Origin: Humerus Insertion: Ulna Action: Extends forearm Two forearm groups: Wrist and finger flexors (on the anterior/palmar side of forearm)Superficial flexors: Pronator teres m., Flexor carpi radialis m., Palmaris longus m., Flexor carpi ulnaris m.Intermediate flexors: Flexor digitorum superficialis m.Deep flexors: Flexor digitorum profundus m., Flexor pollicis longus m., Pronator quadratus m. Wrist and finger extensors (on the posterior/dorsal side of forearm)Superficial extensors: Brachioradialis m., Extensor carpi radialis longus m., Extensor carpi radialis brevis m., Extensor digitorum m., Extensor digiti minimi m., Extensor carpi ulnaris m.Deep extensors: Abductor pollicis longus m., Extensor pollicis brevis m., Extensor pollicis longus m., Extensor indicis m.

What is the muscle at C? Frontalis m. Levator scapulae m. Temporalis m. Occipitalis m.

-Temporalis m.

Which muscle is at letter E? Levator scapulae m. Teres major m. Deltoideus m. Rhomboideus m.

-Teres major m.

Remember, muscle is abbreviated as m. and muscles are abbreviated as mm. - Anatomy Abbreviations -DIAPHRAGM M. The diaphragm m., shaped like a parachute, extends around to cover the entire cavity that separates the thorax from the abdomen. Origin: Several points of origin including the sternum, lower vertebrae, lower ribs Insertion: Central tendon of the diaphragm Action: Contracting downward for inhalation; relaxing upward for exhalation The muscles of the hip are the muscles that involve the flexion and extension of the body at the hip. This would include movements like the splits, a high taekwondo kick, and much more! The muscles of the hip are organized into groups: the iliopsoas group, the gluteal group, and the lateral rotator group.

-The psoas major m. is located deep, adjacent to the spine, and runs all the way down with the iliacus m. to attach to the femur. Origin: Spine Insertion: Femur Action: Flexes thigh -The iliacus m. is large and fan-shaped to line the interior of the pelvis. Origin: Interior pelvis Insertion: Femur Action: Flexes thigh The most superficial muscles of the hip are the gluteal group. The gluteal group's main action is to abduct the hip and extend the thigh. The most superficial muscle of the gluteal group is the gluteus maximus m. Deeper muscles include gluteus medius m. and the gluteus minimus m. -The gluteus maximus m. is the prominent muscle of the buttocks, as it is the largest of the gluteal muscles. Origin: Posterior pelvis and coccyx Insertion: Femur Action: Extends thigh; assists in lateral rotation of the thigh -In order to view the deeper gluteus medius m., the gluteus maximus m. must be removed. The gluteus medius m. lies in between the gluteus maximus m. and gluteus minimus m. Origin: Posterior pelvis Insertion: Femur Action: Abducts thigh -With the gluteus maximus m. removed, the gluteus minimus m. can be seen deep to the gluteus medius m. Origin: Posterior pelvis Insertion: Femur Action: Abducts the thigh and medially rotates the thigh

Currently, you are holding up your head with your neck. You may be smiling with your zygomaticus muscles. Meanwhile, you are blinking using your orbicularis oris muscle. If you are eating, you are chewing with your masseter muscle. Muscles of the Neck We have studied some muscles that support the neck and posture. Not only do the neck muscles hold the head up, but they also flex and extend the head and contribute to other movements, such as lateral head movement. We've studied the intrinsic back muscles and superficial, extrinsic back muscles that contribute to head movement such as the trapezius m., splenius m., and semispinalis m. Let's take a look at two more muscles associated with movements within the neck. The large sheet-like muscle, platysma m., lies superior to deeper neck muscles. Just beneath the platysma m. is the sternocleidomastoid m.

-The sternocleidmastoid m. originates from the sternum and clavicle and inserts on the mastoid process, which is a bony structure of the skull behind the ear. The name itself includes the origin and insertion of the muscle. Origin: Sternum and clavicle Insertion: Mastoid process Action: Flexes neck, laterally flexes neck, rotates neck to the side -Platysma m. is the large sheet of muscle coming up from the pectorals to cover a very large portion of the neck. It is the most superficial muscle in the neck. Origin: Lower neck Insertion: Lower face Action: Moves lower lip and jaw downward

Check all that apply. These muscles can be seen in the image below. Longissimus m. Semispinalis m. Trapezius m. Latissimus dorsi m.

-Trapezius m. -Latissimus dorsi m.

Check all that apply. On the anatomical right side of the body, which muscles were removed to show the deeper muscle layers? Deltoideus m. Trapezius m. Rhomboideus m. Latissimus m.

-Trapezius m. -Latissimus m.

The insertion for muscle C. Digits 2-5 Calcaneus Big toe Little toe

-big toe

Extrinsic Back Muscles The extrinsic back muscles have a wide range of functions that involve the movement of the head, neck, vertebral column, shoulder, and arm. Posterior muscles are grouped according to their physiological location and function. These superficial back muscles are largely associated with upper limb movements. The shoulder, specifically, has many superficial back muscles due to its wide range of motion. Trapezius m. can be easily seen as the broad, flat triangle on the back, while the latissimus dorsi m. is the very large muscle the spans from the lower back up underneath the arm. This is also known as the "lats," which is one of the main muscles used in swimming.

1. Trapezius m.-Origin: Skull, spine Insertion: Clavicle, scapula Action: Elevates scapula (shrugging), retracts scapula (pulls scapula toward midline), depresses scapula 2. Latissimus dorsi m.-Origin: Lower spine and ribs Insertion: Humerus Action: Extends, adducts, and medially rotates the upper arm 3. Teres major m.-Peeking through above the latissimus dorsi m. is the teres major m. This muscle has the same insertion and action as the latissimus dorsi. Origin: Scapula Insertion: Humerus Action: Extends, adducts, and medially rotates the upper arm Underneath the very large trapezius m. and latissimus dorsi m. are the levator scapulae m. and rhomboideus m. -After removing the trapezius m., the levator scapulae m. can be found on the lateral sides of the neck. Origin: Spine Insertion: Scapula Action: Elevates the scapula -After removing both the trapezius m. and the latissimus dorsi m., the rhomboideus m. can be seen inferior to the levator scapulae m. Origin: Spine Insertion: Scapula Action: Elevates and retracts scapula (chest out, shoulders back)

How many ventricles are in the brain?

4

How many compartments are in the leg group and what are their names?

4, anterior compartment, the posterior compartment, and the lateral compartment.

Which muscle is more superficial? The muscle at A or the muscle at B?

A

Moving internal to the three superficial epaxial muscles are the intermediate epaxial muscles, semispinalis m., and multifidus m. The semispinalis m. is superficial to the multifidus m. It has a broader span than the multifidus m. Origin: Upper regions of the spine Insertion: Several vertebrae higher or to the skull Action: Extend neck and head The multifidus m. is located underneath the semispinalis m. Origin: Entire length of the spine Insertion: Attaches a few vertebrae higher Action: Extends vertebral column

Abdominal Muscles There are four muscles that form the abdominal wall, protecting vital organs. God created these muscles to have fibers that run in different directions to strengthen the abdominal wall. The horizontal muscles flex, laterally flex, and rotate the trunk while the vertical muscles stabilize the pelvis and compress the abdomen. The linea alba is the aponeuroses at the midline of the abdominal muscles. Abdominal muscles are listed from the most superficial layer to the deepest layer. The most notable and unique aspects of each layer are the muscle fiber directions. The thorax is the region between the neck and the abdomen. The thorax muscles function for respiration. Muscles of the thorax Part of the thoracic region, intercostal muscles are located "in between" (inter-) the "ribs" (-costal), forming the chest wall. These muscles are responsible for elevating or depressing the ribs for respiration. The diaphragm m. distinguishes the thoracic cavity from the abdominal cavity. Primarily responsible for respiration, the diaphragm m. moves downward for inhalation to create space for air to rush in and upward for exhalation to push the air back out.

What is the action for both muscles B and C?

Adducts thigh

Which of these words does NOT describe fast-twitch muscle fibers?

Aerobic

yperopia is also known as far-sightedness. This occurs when a person has trouble viewing objects that are in close proximity. The light is focused behind the retina, causing blurry vision. Convex lenses are used to correct this visual defect. Myopia is also known as near-sightedness. This occurs when a person has trouble viewing objects that are far away. The light focuses in front of the retina causing blurry vision. Concave lenses are used to correct this visual defect.

Age-related changes of the eye Macular degeneration occurs when your retina is damaged. The person will experience loss of vision in the center of the eye. The center of the macula begins to breakdown. The most common symptom is blurry vision in the center of the eye. Glaucoma occurs due to damage to your optic nerve. It results in increased pressure in the eye. The most common symptom is vision loss. Presbyopia results due to the hardening of the lens. The lens is unable to change shape to accommodate for focusing on objects in close proximity, which results in blurry vision with close images.

Which of these words does NOT describe slow-twitch muscle fibers?

Anaerobic

Types of Movement Muscles can induce a variety of motions: flexing, extending, abduction, adduction, rotation, depression, and elevation. To understand the rest of the muscles module, you must completely master your knowledge of the types of movement. Click on the items below to learn more about each type of muscle movement. Spend a decent amount of time working through and understanding each type. Specialized Movements in the Upper Body 1. Protracting the scapula- By protracting the scapula, the arms move forward in this "hugging" motion. 2. Retracting the scapula- By retracting the scapula, the arms move backward in this "flying" motion. 3. Supination-Maintaining anatomical position, when the forearm is positioned with the palms facing up, the forearm is in a supine position. A way to remember that is that you hold soup in the supine position.

Angular Movements 1. Flexion and Extension-Flexors and extensors adjust and change the angle between two body parts. Flexion decreases the angle between the two body parts. For example, when you move the arm/hand inward towards the body, you are flexing your biceps brachii muscle. If you decrease your body angle by bending your hips, you are flexing your hips. On the other hand, extension increases the angle between the two body parts. For example, when the arm opens the angle of the elbow joint, working the triceps brachii muscle, you are extending your arm. Standing up straighter, or even leaning back, would be an extension. Move your head to flex your neck and extend your neck. Think about the movements and tell yourself which movement is a flexed or extended movement. 2. Abduction and Adduction-Abduction and adduction are movements relative to the midline of the body. Abduction is the movement away from the midline of the body, and adduction is the movement towards this line. For example, moving the limbs (arms or legs) away from the body is abduction, and bringing them back to the midline is adduction. 3. Rotation- Internal or medial rotation is specific to the shoulder or hip and brings the distal portions of the limbs inwards towards the midline. Internal rotation can also move the humerus and femur inward. External or lateral rotation is the opposite movement, pointing the distal portion of limbs as well as the humerus and femur away from the mid-line.

Smooth muscles are found in _______ . Cardiac muscles are found in walls of heart . Skeletal muscles are found in ________

Answer 1:walls of internal organs Answer 2:walls of heart Answer 3:attached to skeleton

Check all that apply. Functions for muscles include: Generating heat Movement Maintaining posture Absorbing nutrients

Answers- 1.Generating heat 2.Movement 3.Maintaining posture

Which of these would be distributed over wider area of muscles and across flatter muscles?

Aponeuroses

Which glial cell resembles a star?

Astrocyte

These CNS neuroglia are star-shaped and contribute to the blood-brain barrier.

Astrocytes

Which nervous system we can't voluntarily control?

Automic nervous system

The part of the neuron that transmits electrical signals away from the cell body.

Axon

Where are neurotransmitters stored?

Axon terminal

What is the insertion of the muscle at G?

Base of metacarpals 2 and 3

What muscle is located at letter A?

Biceps femoris m.

This neuron shape is commonly found in special sensory structures like the eye and ear. This neuron has only two processes extending from the cell body.

Bipolar neuron

What are the two main parts of the inner ear?

Bony labyrinth and membranous membrane

Which muscle is located at G?

Brachioradialis m.

Abductor pollicis longus m. - The abductor pollicis longus m. moves the thumb. "Pollex" is the Latin word for thumb. Origin: Radius and ulna Insertion: Base of thumb Action: Abducts and extends thumb Extensor pollicis brevis m. - The extensor pollicis brevis m. moves the thumb and abducts the hand. "Pollex" is the Latin word for thumb. Origin: Posterior radius Insertion: Base of thumb knuckle Action: Extends thumb and abducts hand Extensor pollicis longus m. - The extensor pollicis longus m. moves the thumb and abducts the hand."Pollex" is the Latin word for thumb. Origin: Posterior ulna Insertion: Distal thumb Action: Extends thumb and abducts hand Extensor pollicis indicis m. - The extensor pollicis indicis m. moves the index finger. Origin: Ulna Insertion: Posterior index finger Action: Extends index finger

Brachioradialis m. - The brachioradialis m. is located superficially and can be seen on both anterior and posterior views of the forearm. It is considered a flexor, but it originates on the posterior side of the arm. Origin: Humerus Insertion: Wrist of the radius bone Action: Flexes forearm Extensor carpi radialis longus m. - The matching pair of muscle for the extensor carpi radialis longus m. is the extensor carpi radialis brevis m. They both originate from the humerus and attach to the base of the hand. Origin: Humerus Insertion: Base of hand Action: Extends hand & abducts hand Extensor carpi radialis brevis m. - The matching pair of muscle for the extensor carpi radialis longus m. is the extensor carpi radialis brevis m. They both originate from the humerus and attach to the base of the hand. Origin: Humerus Insertion: Base of hand Action: Extends hand Extensor digitorum m. - The extensor digitorum m. is the main extensor of the fingers. Origin: Humerus Insertion: Fingers 2-5 Action: Extends hand; extends fingers Extensor digiti minimi m. - Some people do not have a defined extensor digiti minimi m. It originates from the extensor digitorum and attaches to the little finger. Origin: Humerus Insertion: Finger 5 Action: Extends finger 5 Extensor carpi ulnaris m. - On the ulna side of the posterior forearm is the extensor carpi ulnaris m. Origin: Humerus and ulna Insertion: Base of hand Action: Extends and adducts hand

What are the components of the nervous system?

Brain, spinal cord, and peripheral nerves

What is the muscle at G? Platysma m. Orbicularis occuli m. Masseter m. Buccinator m.

Buccinator m.

The only intermediate layer in the forearm flexor is the flexor digitorum superficialis m. Where is this muscle located?

C

Describe how the muscular system works with one of these systems. Skeletal system Cardiovascular system Digestive system Nervous system

CHOOSE ONE AND WRITE IN YOUR OWN WORDS- FROM LESSON: The muscular system works with: Skeletal system: To maintain posture and control movement Cardiovascular system: Muscles in the heart contract for the heart to pump blood Digestive system: Smooth muscle in the digestive system allows peristalsis, letting food move through the digestive tract Nervous system: Muscles receive neural impulses from the brain that control muscle contractions

What gland produces ear wax?

Ceruminous glands

What type of muscle helps to change the pupil size when focusing on objects?

Ciliary body

Where is the Organ of Corti located?

Cochlear duct

The frontal and parietal bones come together to form this suture.

Coronal suture

"... to put off your old self, which belongs to your former manner of life and is corrupt through deceitful desires, and to be renewed in the spirit of your minds, and to put on the new self, created after the likeness of God in true righteousness and holiness." -Ephesians 4:22-24 The human brain contains almost 97% of the body's neural tissue and weighs about 3 lbs. Anatomically, there are six main regions of the brain: the cerebrum, the cerebellum, the diencephalon, the midbrain, the pons, and the medulla oblongata. Like the spinal cord, the brain belongs to the central nervous system, and it is covered by the same three meningeal layers (pia mater, arachnoid mater, and dura mater). The brain is protected by the skull.

Cranial Meninges There are three meningeal layers found surrounding the spinal cord and the brain. The order of these three layers, from superficial to deep, is the same as in the vertebral canal: dura mater, arachnoid mater, and pia mater. Also present is the subarachnoid space between the pia mater and arachnoid mater, which holds cerebrospinal fluid (CSF) as well. Unique to the cranial cavity, the dura mater is made up of two smaller layers: an outer periosteal layer and an inner meningeal later. In most locations, these two layers are attached to one another forming a single layer of dura mater. In special locations, these two layers split. Where they split, the space between the two layers is called a dural venous sinus. This space holds venous blood. The Diencephalon The diencephalon is made up of three primary components: the hypothalamus, thalamus, and pineal gland. The thalamus relays incoming sensory information to its appropriate location in the cerebrum (e.g., it will relay visual signals carried by the optic nerve to the occipital lobe of the cerebrum where these signals will be perceived). The hypothalamus sits just below and slightly anterior to the thalamus. It regulates the autonomic nervous system as well as controls hormone secretion at the pituitary gland. The pineal gland is posterior to the thalamus and is involved in regulating the sleep/wake cycle.

Shorter processes extending from the cell body.

Dendrites

This muscle separates the thoracic cavity from the abdominal cavity.

Diaphragm

The wrist joint is ____ to the elbow joint.

Distal

What type of action involves pulling the foot towards the leg?

Dorsiflexion

When you raise your toes towards your face, the movement in the leg is called:

Dorsiflexion

Match the movement to the muscle action. Bringing toes up to look at shoelaces Falling laterally and rolling ankle during basketball Tip toes

Dorsiflexion-Bringing toes up to look at shoelaces Inversion- Falling laterally and rolling ankle during basketball Plantarflexion-Tip toes

Name the three meningeal layers.

Dura, Arachnoid, and Pia

Name the organ that response to the motor signal.

Effector organ

What is the action of the muscle at letter B?

Elevates ribs, protracts scapula

Both muscles A and B have this action.

Elevates the scapula

This system is sometimes considered part of the automatic nervous system, and it controls the digestive system.

Enteric nervous system

Which glial cell forms an epithelial lining in the brain and spinal cord?

Ependymal cell

These CNS neuroglia are involved in the production of cerebrospinal fluid (CSF).

Ependymal cells

Hearing Sound waves from the external environment travel from the external ear to the inner ear. External Ear Sound waves are collected by your auricle and travel through your external auditory canal to your tympanic membrane. Middle Ear After sound waves hit the tympanic membrane, they vibrate the three bones of the middle ear: the malleus, incus, and stapes, and activate the oval window. Inner Ear The vibration of the oval window activates the perilymph liquid to form pressure waves in the scala vestibule. The main organ of hearing is the receptors from the organ of Corti, located in the cochlear duct. The pressure bends the basilar membrane, which causes the hair cells to vibrate. The information is received and transmits a nerve impulse. The nerve impulse is initiated by the organ of Corti and sent to the brain by the cranial nerve: vestibulocochlear nerve (CN 8).

Equilibrium The inner ear is mainly responsible for balance, or equilibrium. It takes place in the vestibule and semicircular canals. There are two types of equilibrium that play a role in equilibrium: static and dynamic. Static equilibrium is related to head movement due to gravity. This occurs when the body is at rest. The body has the ability to sense head position by bending the hair cells in the semicircular canals. Dynamic equilibrium is related to positional head movement, specifically horizontal and vertical rotation. When the body is moving, the hair cells in the semicircular canals bend and start nerve impulses. Age-related Changes in the Ear Hearing is affected as we age. The most common issue is gradual or sudden hearing loss, referred to as presbycusis. The most common reason for this is the breakdown of hair cells in the inner ear.

Which bone separates the nasal cavity from the brain?

Ethmoid bone

Which of the following drains fluid from the ear?

Eustachian tube

When you move your right foot out to the right side, the movement in the leg is called:

Eversion

What is the action of the triceps brachii m.?

Extends forearm

Which muscle is located at I? Brachioradialis m. Extensor digitorum m. Extensor carpi radialis brevis m. Extensor carpi radialis longus m.

Extensor carpi radialis brevis m.

What muscle is located at H?

Extensor carpi radialis longus m.

Which muscle is at A? External oblique m. Rectus abdominis m. Internal oblique m. Transversus abdominis m.

External oblique m.

-External intercostal mm. are the most superficial of the intercostal mm. From the lateral to the medial side, the muscle fiber direction is angled downward. To help you with the muscle fiber direction, imagine your "hands in pocket" for the external intercostal mm. Origin: Rib below Insertion: Rib above Action: Elevates rib during inspiration -Deep to the external intercostal mm. are the internal intercostal mm. From the lateral to the medial side, the muscle fiber direction is angled upward. To help you with the muscle fiber direction, imagine your "hands in prayer" for the internal intercostal mm. Origin: Rib below Insertion: Rib above Action: Depresses rib cage during expiration

External oblique m. - The most superficial layer of the abdominal wall is the external oblique m. From the lateral to medial sides, the fiber directions are angled downwards. To help you with the muscle fiber direction, imagine your "hands in pocket." Origin: Lower ribs Insertion: Pelvis, linea alba Action: Supports abdomen; flexes vertebral column Internal oblique m. - The next layer of the abdominal wall is the internal oblique m. From the lateral to medial sides, the fiber directions are angled upwards. To help you with the muscle fiber direction, imagine your "hands in prayer." Origin: Pelvis Insertion: Linea alba, ribs Action: Supports abdomen; flexes vertebral column - The deepest layer of the abdominal wall is the transversus abdominis m. The fibers run from the posterior to the anterior side of the body. The fiber directions run laterally. Origin: Pelvis, thoracolumbar fascia Insertion: Linea alba, sternum, pelvis Action: Supports abdomen - Rectus abdominis m. is located between the rectus sheath (extensions of external oblique, internal oblique, and transversus abdominis mm.). These are the "six-pack abs;" however, there are eight sections in the rectus abdominis m. The muscle fibers run up and down. Origin: Pelvis Insertion: Sternum and Ribs Action: Flexing vertebral column

The lacrimal apparatus functions as a pathway in the eye for the production and removal of tears. The lacrimal gland produces tears, which travel along various ducts in the eyes to the lacrimal canaliculi. The lacrimal canaliculi is a tunnel that collects the tears and leads to the lacrimal sac and lastly to the nasolacrimal duct. The nasolacrimal duct leads to the nasal cavity. This connection explains why your nose runs when you cry.

Extrinsic eye muscles There is a total of 6 eye muscles surrounding the eye to help with movement. There are four rectus muscles: superior, inferior, lateral, and medial. The final two muscles are oblique: superior and inferior. Rectus muscles: Superior rectus lifts the eye. It is located on the superior portion of the eye and is controlled by the oculomotor nerve (CN3). Inferior rectus moves the eye down. It is located on the inferior portion of the eye and controlled by the oculomotor nerve (CN3) Medial rectus moves your eye closer to your nose. It is located on the medial side of your eye and is controlled by the oculomotor nerve (CN3). Lateral rectus moves your eye away from your nose. It allows you to look out the corner of your eye. It is located on the lateral side of your eye and controlled by the abducens nerve (CN6). Oblique muscles: Superior oblique moves eye down, medial and lateral rotation. It is located under the superior rectus and controlled by the trochlear nerve (CN4). Inferior oblique lifts the eye and medial and lateral rotate. It is located under the lateral rectus and controlled by the oculomotor nerve (CN3).

Which of these has the appearance of a spider's web? (Fascial muscles are also attached to this.)

Fascia

Muscle Organizational Levels The muscle is organized by: Muscle (organ) --> Fascicle (part of organ) --> Muscle fiber (cell) --> Myofibril (organelle) Sarcomere Sarcomere regions (I band, Z disc, A band, H zone, M line) Myofilaments (macromolecule)Actin Myosin Sliding Filament Model of Contraction Myofibrils consist of long filaments of actin, myosin, and other proteins. The proteins are organized into sections called sarcomeres, which is the contractile unit of a muscle cell. The organization of the sarcomeres gives muscles their distinctive striated appearance. Actin and myosin are interlaced with each other and slide over each other—a process known as the sliding filament model of contraction.

Fascicle Arrangement in Muscles Muscles are categorized based upon the anatomical arrangement of fascicles: bundles of muscle fibers. The four subcategories are parallel, convergent, pennate, and circular. Parallel muscles have fascicles (groups of muscle cells) that run parallel to one another. Most of the body's skeletal muscles are parallel muscles. Parallel muscles can be further divided into fusiform and non-fusiform. Fusiform parallel muscles have a thicker diameter muscle body that becomes smaller towards the end of the muscle (for example, biceps brachii m. located in the arm). Non-fusiform parallel muscles are more square (for example, rectus abdominis m. located on the abdomen). Convergent muscles have a common origin, and then the fascicles extend outwards to allow the muscle to cover a broad surface. The broad covering allows the muscle to complete more versatile movement (for example, pectoralis major m.). Pennate muscles have a tendon running through the whole length of the muscle. The fascicles pull on the tendon from an angle and create a feather-like shape. The feather shape is why these muscles are called pennate. If all the fascicles are on one side of the tendon, the pennate muscle is called unipennate (for example, palmar interosseous m. between the metacarpals of the hand). If the fascicles are on both sides of the tendon, the pennate muscle is called bipennate (for example, rectus femoris m. in the thigh). Multipennate has multiple fascicles on both sides of the tendon (for example, deltoid m. on the shoulder). Circular or sphincter muscles are arranged around an opening. As circular muscles contract, the opening becomes smaller (for example, orbicularis oris m. controlling the opening of the mouth).

What is the action of the muscle at D?

Flexing vertebral column

Generation of action potential Neurons communicate with each other through action potentials. Resting potential- This occurs when there's a difference in concentration inside and outside the cell. Sodium voltage gates are closed. Threshold potential- This is the minimum potential need to produce an action potential. Depolarization- Sodium channels open and there is an increase entering the cell. This causes the cell to become more positive. Repolarization- Sodium channels close and potassium channels open. This causes more potassium to leave the cell. Hyperpolarization- Potassium channels remain open and cells become more negative.

Fours Types of Neurons (Based on Their Structure) In the first two images of the neuron displayed in this lesson, there is a cell body (which contains the nucleus) connected to many dendrites and a single axon. The name for this neuron "shape" is referred to as multipolar. It is referred to as "multipolar" because there are many (multi) processes connected to the cell body. The majority of the neurons in the nervous system are of this shape, which is why this shape is often used to describe a typical neuron. However, neurons come in other shapes as well. Some of the neurons in the retina of the eye (that help us see) and neurons in the nose (that help us smell) have a different shape. These neurons have a single cell body (like the multipolar neuron) and only two processes extending from that cell body, hence they are referred to as bipolar. Many of the sensory neurons (other than the "special" senses in the eye and nose) have a different shape in which a single cell body is attached to a single process. This shape is referred to as unipolar. In humans, unipolar neurons are more commonly referred to as "pseudo-unipolar" neurons, since the "true" unipolar shape is seen only in invertebrates.

Name the bone in yellow.

Frontal bone

Ventricles and CSF The ventricles are interconnected cavities within the cerebral hemispheres and brainstem. These cavities are filled with cerebrospinal fluid (CSF), and each ventricle contains tissue that produces the CSF. In total, there are four ventricles in the brain: two lateral ventricles, the third ventricle, and the fourth ventricle. The fourth ventricle sits between the brainstem and the cerebellum. The cerebral aqueduct allows CSF to flow from the third to fourth ventricles. Cerebrospinal fluid (CSF) is a clear liquid that fills the four ventricles and interconnecting canals, the subarachnoid space, and the central canal of the spinal cord. The CSF allows the brain to float in a neutrally buoyant environment. It provides protection (by cushioning the brain from hitting the inside of the skull) as well as chemical stability, allowing for waste products to be rinsed away.

Functions of the Nervous System The primary function of the nervous system is to coordinate bodily activities. Three processes are involved in this function: sensory function, information processing, and motor function. Sensory Function: The nervous system can monitor ongoing changes occurring both inside and outside the body. Information is gathered by receptors (referred to as sensory input). This information is sent via electrical impulses (via neurons or nerve cells) ultimately to the brain by way of sensory nerves. Information Processing: The sensory input that has been collected by the brain will be integrated in order to create any of the following: sensations, memory, thoughts, decisions. Sometimes, the brain will elicit a motor response from this sensory information. Motor Function: The motor function may be the response from either a conscious or unconscious decision that took place in the brain. This motor response is carried via electrical impulses to other organs (e.g., a skeletal muscle or a gland) in the body. The organs that respond to these motor signals are referred to as effector organs.

Match the stage of the cell cycle with its characteristics.

Gap 1 and Gap 2- In this stage, the cells will continue their normal functions. Synthesis-In this stage, the cell will copy its nuclear DNA. At the end of this stage, the cell has 2 complete sets of DNA in the nucleus. Mitosis-The nucleus and the contents inside it divide.

What condition causes increased pressure in the eye?

Glaucoma

What is another name for neuroglia?

Glial cells

Which superficial muscle has been removed on the left side of the body in this image?

Gluteus maximus m.

Which letter represents the strongest chewing muscle?

H

What is the origin of the muscle at H?

Humerus (medial elbow)

Name the three parts of the diencephalon.

Hypothalamus, Thalamus, and Pineal gland

Which muscle is shown at A? (skeletal muscle-spine)

Iliocostalis m.

The two chambers in the eye: anterior and posterioR both contain fluid called aqueous humor. The posterior chamber has an additional gel-like substance called the vitreous humor. The anterior chamber's main location is between the iris and cornea. It assists in regulating intraocular pressure in the eye. The posterior chamber's main location is between the iris and the lens. It assists in maintaining the shape of the eye. Lens The lens is located behind the cornea and is held in place by the ciliary body. The lens assists in the eye's ability to focus on objects. As light enters the lens, it bends and focuses light on the retina by changing shape.

Image formation Refraction is defined as the bending of light and it measures the eye's ability to focus on light rays as they enter the eye. Errors can occur due to eye length and curvature of the lens and cornea. Refraction is also used to determine the need for corrective lenses. Once light enters the eyes, it sees objects as upside down and reversed. The brain is able to convert the image correctly. There are 4 refractory structures of the eye: cornea, lens, aqueous and vitreous humor. The lens has the ability to bend and change shape to adjust for clear vision. The ciliary muscle helps in changing the shape of the lens. Vision The lens adjusts to changes in the distance of images. For close objects, the lens becomes more circular, and ciliary muscles contract for better focus. For objects further away, the lens becomes flatter and the ciliary muscles relax. This is considered accommodation. There are three events that occur when focusing on objects in close proximity: accommodation, pupillary constriction, and convergence. The pupils change shape to focus on closer objects. Pupils will become smaller for better focus on objects in close proximity. This is considered pupillary constriction. As objects move closer, the eyes will rotate medially for better focus. This is called convergence. Emmetropia is also known as normal vision. There are no visual defects.

List and briefly describe the 4 lobes of the cerebral hemisphere.

In your own words- 4 lobes of the cerebral hemisphere include: the frontal, parietal, occipital, and temporal. Frontal- Controls skeletal muscle contraction Parietal- Helps interpret touch Occipital- is associated with vision Temporal- Plays a role in hearing

Functions of the Nervous System The primary function of the nervous system is to coordinate activities in the body. The three processes involved in this function are sensory input, information processing, and motor output. Sensory Input: The nervous system is able to monitor ongoing changes occurring both inside and outside the body. Information is gathered by receptors (referred to as sensory input), and this information is sent via electrical impulses (via neurons or nerve cells) ultimately to the brain by the way of sensory nerves.

Information Processing: The sensory input that has been collected by the brain will be integrated in order to create any of the following: sensations, memory, thoughts, decisions. Sometimes, the brain will elicit a motor response from this sensory information. Motor Output: The motor output may be the response from either a conscious or unconscious decision that took place in the brain. This motor response is carried via electrical impulses to other organs (e.g., a skeletal muscle or a gland) in the body. The organs that respond to these motor signals are referred to as effector organs. Three Types of Neurons (Based on Function) A nerve is a bundle of axons in the Peripheral Nervous System (PNS). Sensory nerves contain the axons of sensory neurons while motor nerves contain the axons of motor neurons. Sensory (or afferent) neurons are always transmitting their electrical signals in a direction towards the Central Nervous System (CNS) while motor (or efferent) neurons transmit their electrical signals away from the CNS. Within the CNS, and often found between sensory and motor neurons, are interneurons. Interneurons are only within the brain and spinal cord, and they make up the majority of the neurons within the nervous system. A sensory neuron will become activated and transmit an electrical signal towards the CNS. A synapse forms between the sensory neuron and an interneuron within the spinal cord. The interneuron is shown synapsing with a motor neuron. Once the motor neuron is activated, electrical impulses will travel down its axon in a direction away from the CNS. The motor neuron will stimulate a skeletal muscle (e.g., the biceps brachii is shown in the image) to contract, flexing the elbow and removing the hand from the heat source of the flame.

The three bones that make up the auditory ossicles are the smallest in the body. The malleus, which is shaped like a hammer, attaches to the tympanic membrane. The incus- sometimes called the anvil- receives vibrations from the malleus and transmits them to the stapes. The stapes, shaped like a stirrup, connect to the incus and the oval window leading to the inner ear. The oval window separates the middle ear from the inner ear. The stapes bone is attached to the oval window. As vibrations are transferred through each ossicle, they arrive at the oval window to be transmitted into the inner ear.

Inner Ear The inner ear begins at the oval window. The inner ear is made up of two main parts: bony labyrinth and membranous labyrinth. The inner ear- often called the labyrinth- consists of a series of fluid-filled tubes within a bony chamber. The bony labyrinth is a series of tunnels, surrounded by the temporal bone. Inside it are the vestibule, semicircular canals, and cochlea. All three parts contain perilymph fluid. The vestibule and semicircular canals are responsible for balance, while the cochlea is the organ of hearing. The vestibule contains two fluid-filled sacs called the saccule and utricle. These structures assist with balance. The semicircular canal is actually three joined canals: the anterior, posterior, and horizontal canals. Each of these fluid-filled tubes senses a particular direction of movement in the head based on how they are oriented. As the head moves, the fluid moves, and sends signals to the brain about head movement. The cochlea is the part of the bony labyrinth that looks like a snail shell. It is responsible for hearing. It contains hair cells inside the Organ of Corti that transmit various wavelengths of sound in the form of vibrations to the brain. The brain in turn interprets the electrical signals into pitch and sound. The membranous labyrinth is located inside the bony labyrinth. It contains membranous tunnels, as well as fluid-filled tubes of endolymph.

What type of neuron is found between the sensory and motor neurons?

Interneuron

Note: Muscles are all over the body and have become a representative system for the covers of many anatomy textbooks. In anatomy, the word "muscle" is used so often that it is abbreviated as m. for "muscle" and mm. for "muscles." So, the deltoid muscle becomes deltoid m. You may see this abbreviation in this course. Anatomical Position: A person is standing upright, facing forward, arms at the side, palms facing forward—this position is used when describing the body parts in relation to one another.

Intrinsic vs. Extrinsic Back Muscles We will first study the intrinsic back muscles. "Intrinsic" means to belong solely to that body part, which in this case would be the back. The deeper intrinsic back muscles can only be seen if all of the superficial muscles are removed. Think of the intrinsic back muscles as the support and foundation to keep the back straight. If you think about these muscles pulling on the skeleton, you can see how the spine would straighten. The back muscles that you see on exercise machines or on muscle posters are extrinsic back muscles. "Extrinsic" means outward, which in this case, the most superficial back layers actually control upper limb movement. Intrinsic back muscles support movement within the vertebral column. They are the deeper muscles in the back that have attachment sites to the spine. Posture and balance depend on these muscles and erect the spine. Hence, superficial erector spinae muscles include the iliocostalis m., longissimus m., and the spinalis m. The intermediate layers underneath the erector spinae muscles are semispinalis m. and multifidus m. We will not be covering the deeper epaxial muscles in this course. Bone surface markings, muscle movements, anatomical positions, directional terms, and relative positions of other anatomical structures are used to study and describe the muscles' structure and function. Each muscle will have an "origin" and "insertion" which describe where the muscle attaches. The origin is the site that does not move during muscle contraction, whereas the insertion is the site that moves during muscle contraction.

The most common ankle injury is when you "roll the ankle." The sole of the foot moves inward. What kind of movement is this?

Inversion

What type of action involves tilting the sole inward?

Inversion

Check all that apply. These movements occur within the muscles of the leg.

Inversion Dorsiflexion Eversion Plantarflexion

P is the tendon of which muscle?

K

What structures make up the lacrimal apparatus?

Lacrimal gland, lacrimal canaliculi, lacrimal sac, and nasolacrimal duct

What compartment do muscles A and B belong to?

Lateral

What is muscle B's insertion?

Linea alba, ribs

Check all that apply. Which statements apply to the extensor carpi ulnaris m.?

Located on the posterior forearm Origin: Humerus and ulna Insertion: Base of hand Action: Extends and adducts hand

Which muscle is shown at B? (spine skeletal)

Longissimus m.

Which ear bone is shaped like a hammer?

Malleus

Which three bones vibrate in the middle ear?

Malleus, incus, stapes

The strongest chewing muscle.

Masseter m.

Which muscle is shown at H?

Masseter m.

The scientific term for chewing.

Mastication

These CNS neuroglia can engulf debris and dead tissue.

Microglia

Intrinsic Back Muscles- Superficial Epaxial Muscles The splenius m. is the first muscle along the back of the neck that extends the neck and head. Origin: Upper spine Insertion: Posterior skull Action: Extends head and neck The erector spinae group are the strongest back muscles, as they are responsible for posture and overall stabilization of the entire body. Three superficial epaxial muscles, also known as the erector spinae, from lateral to medial are the iliocostalis m., longissimus m., and the spinalis m.

Most laterally located of the erector spinae group is the iliocostalis m. Origin: Pelvis, spine, and a common tendon for the erector spinae group Insertion: Ribs and lower neck Action: Extends vertebral column and head The largest of the three muscles of the erector spinae group is the longissimus m. Origin: Pelvis, spine, and a common tendon for the erector spinae group Insertion: Ribs, spine, skull Action: Extends vertebral column and head The most medial and smallest muscle of the group is the spinalis m. Origin: Pelvis, spine, and a common tendon for the erector spinae group Insertion: Spine and skull Action: Extends vertebral column and head

This is the MOST common neuron shape.

Multipolar

Eyebrows help to protect the eye from liquids such as sweat getting inside. They can also provide a cover from direct sunlight exposure. Eyelids help to lubricate the eye and remove any foreign material using a blinking motion. Blinking spreads tears and mucus to assist in keeping eyes moisturized. Eyelashes can serve many functions other than enhancing beauty. They provide protection to the eye by catching foreign particles in hair follicles. They can also serve as a cover from light. Conjunctiva is a thin tissue covering the white part of your eye. It releases fluid to help lubricate the eye and protect from foreign material entering inside.

Muscles of the Head and Face The accordion organizer allows you to maximize and minimize the information for each muscle. Keep only one muscle open at a time for quicker reference to the image of the muscles of the head and face. Frontalis m. - The frontalis m. is located on the frontal bone. The muscle serves to provide facial expressions. Origin: Top of the head Insertion: Orbicularis oculi m. Action: Raises eyebrows Orbicularis oris m. (mouth muscle) - The orbicularis oris m., not to be confused with orbicularis oculi (eye), surrounds the mouth. Origin: Jaws Insertion: Skin surrounding lips Action: Puckers lips Temporalis m. - Located on the side of the head is the temporalis m. Origin: Temporal side of the skull Insertion: Upper jaw Action: Elevates the upper jaw Orbicularis oculi m. (eye muscle) - The orbicularis oculi m. (eye), not to be confused with orbicularis oris (mouth), surrounds the eye. Origin: Frontal bone, the bone around eyes Insertion: Around the eye Action: Blinks and closes the eyelid Zygomaticus m. - Zygomaticus m. is known as the smiling muscle. Origin: Cheekbone Insertion: Side of mouth Action: Smiling Buccinator m. - Buccinator is the muscle in your cheek. It is used for keeping the cheek against your teeth, which is useful for actions like whistling, blowing, smiling, or sucking. Musicians, such as those who play wind instruments can have strong buccinator muscles. Origin: Cheek Insertion: Orbicularis oris Action: Keeps cheek against teeth, chewing and suckling Masseter m. - Mastication, the chewing movement, directly involves the masseter m, a square-shaped muscle on both sides of the jaw. Masseter m. is the strongest chewing muscle. Origin: Below eye Insertion: Lower jaw Actions: Elevates the jaw

Anterior Compartment Tibialis anterior m., extensor hallucis longus m., and extensor digitorum longus m. dorsiflex the foot. -The tibialis anterior m. is located alongside the lateral surface of the tibia and is the strongest dorsiflexor of the foot. Origin: Lateral surface of tibia Insertion: Big toe Action: Dorsiflexes and inverts foot -"Hallux" is a person's big toe. The name extensor hallucis longus m. means that it "extends the big toe." Origin: Fibula Insertion: Big toe Action: Extends big toe and dorsiflexes the foot -A deeper muscle splits into four to extend to the digits, the extensor digitorum longus m. Origin: Anterior fibula Insertion: Toes 2-5 Action: Extends toes 2-5 and dorsiflexes the foot

Muscles of the leg can be split into three categories: the anterior compartment, the posterior compartment, and the lateral compartment.This section is on the posterior compartment. Posterior Compartment The gastrocnemius m. and soleus m. are located in the posterior compartment. The soleus m. is deep to the gastrocnemius m. They plantarflex the foot and flex the leg. There are several other deep muscles in the posterior compartment, such as the tibialis posterior m., flexor digitorum longus m., and the flexor hallucis longus m. -Gastrocnemius m. is the calf muscle. It inserts via the achilles tendon, which is fibrous tissue that connects to the calcaneus bone (heel bone). Origin: Femur Insertion: Posterior calcaneus via achilles tendon Action: Plantar flexes foot; flexes leg -Soleus m. can be seen if the superficial layer, the gastrocnemius m., is removed. Origin: Fibula, medial border of tibia Insertion: Posterior calcaneus via achilles tendon Action: Plantar flexes foot; flexes leg

In the diagram below, identify the structure at E.

Myofibril

Concave lenses are used to correct this visual defect.

Myopia

What Are the 5 Golden Rules of Skeletal Muscle Activity? All skeletal muscles cross at least one joint. The bulk of the skeletal muscle lies proximal to the joint crossed. All skeletal muscles have at least two attachments: the origin and the insertion. Skeletal muscles can only pull; they never push. During contraction, the muscle insertion moves toward the muscle origin.

Naming Muscles Names are important to identify muscles. Think about your own name: how did you get your name? Someone chose that name for you, or your last name may have had an origin. Perhaps you are named after a grandparent. Muscles can be named after their location, shape, size, fiber direction, number of origins, location of attachments (origin and insertion), and/or action. 1. Location: The temporalis muscle is located on the temples. 2. Shape: The rhomboidal muscle has a rhomboid shape. 3. Size: The gluteus maximus and gluteus minimus are named by the relative size of the muscles. 4. Direction of fibers: The rectus abdominis muscle has the word "rectus" because it is straight. 5. Number of origins: The biceps brachii muscle is named because there are two heads. 6. Location of the muscle's origin and insertion: The sternocleidomastoid muscle is named because it originates on the sternum and clavicle, and inserts on the mastoid process. 7. Action of the muscle: Flexor digitorum superficialis flexes the fingers. Location: The temporalis muscle covers the temporal portion of the skull. Shape: Rhomboidal muscle is named for its rhomboid shape. Size: Gluteus maximus and gluteus minimus muscles are distinguished because of their size. Direction of Fibers: The straight fibers of the rectus abdominus create the look of "6-pack abs." Number of Origins: Biceps brachii are located on the arm and have two heads ("bi-") at the point of origin. Location of the Muscle's Origin and Insertion: The Sternocleidomastoid muscle priginates at the sternum and inserts on the mastoid process. Action of the Muscle: The Flexor digitorum superficialis muscle flexes the forearm.

The "support cells" of the nervous system. These cells DO NOT transmit electrical signals.

Neuroglia

Neuron Structure As mentioned in the last lesson, the primary functional cell within the nervous system is called the neuron. Neurons have three basic regions: the cell body (which houses the nucleus), many short processes called dendrites, and one long axon. In the image of a neuron below, you will notice that this axon contains a green covering called myelin (not all axons are myelinated like this). Synapse Neurons are able to communicate with other cells at special locations called synapses. A synapse is where the end of an axon (referred to as the axon terminal) comes into close proximity to another neuron (typically at its dendrite or cell body). The first neuron is called the presynaptic neuron, and the second neuron is called the postsynaptic neuron. The "space" between these two neurons is called the synaptic cleft.

Neuroglial Cells Support Neurons The neuron is not the only cell found in the nervous system. In addition to neurons, there are "support" cells referred to as neuroglial cells (also called glial cells or neuroglia). There are different six types of glial cells, and they have a variety of functions, from helping to myelinate the axons to providing mechanical support in the brain. Glial cells also play a role in the formation of the blood-brain barrier which helps to protect the brain from certain chemicals that might be present in the blood circulation. The Axon and Axon Terminal Compared to neuroglial cells, neurons are the only cells in the nervous system that are capable of transmitting electrical signals. The electrical signal begins at the site where the axon emerges from the cell body (a region referred to as the axon hillock). Once a certain threshold is reached at this location, the electrical signal will travel down the length of the axon until it reaches the axon terminal at its end. The axon terminal stores neurotransmitters, so the arrival of the electrical signal to the axon terminal will result in the neurotransmitter being released into the synaptic cleft.

These are the functional cell of the nervous system that can communicate via electrical signals.

Neurons

What do chemical synapses rely on to spread action potentials?

Neurotransmitters

The skull protects the brain and other delicate inner parts of the head, like the eyes, nasal cavity, and oral cavity. In addition, the skull is an attachment site for the muscles of the face. When you smile, the muscles pull your mouth outwards by anchoring onto the zygomatic process of the temporal bone. The skull is formed by several bones which, with the exception of the mandible, are joined together by sutures (immovable joints). The adult human skull is comprised of twenty-two bones which are divided into (1) neurocranium (8 cranial bones) and (2) viscerocranium (14 facial bones). Neurocranium The neurocranium is made up of eight cranial bones and the cranial cavity. The cranial bones surround and protect the brain and brainstem. The eight cranial bones include the occipital bone, two temporal bones, two parietal bones, sphenoid bone, ethmoid bone, and frontal bone. These bones are joined together by sutures.

Occipital Bone The occipital bone is located at the skull's base at the cranium's rear. It is the bony area in the skull just above the neck. The occipital bone articulates, or forms a joint, with the first vertebra of the vertebral column. Within the vertebral column is your fragile spinal cord. The spinal cord passes through the inferior opening of the skull, called the foramen magnum. Imagine a train that needed to pass through a rocky mountain—that train could pass through a tunnel. In the same way, the spinal cord exits the skull through the foramen magnum of the occipital bone. Temporal Bones (2) Temporal bones are a pair of bones that are bilateral and symmetrical. A large portion of the lateral and base part of the skull is made up of these temporal bones. The temporal bones are irregularly shaped bones that have numerous muscle attachments and articulations with other bones. Parietal Bones (2) The two large parietal bones form the roof and sides of the human skull. Sphenoid Bone The sphenoid bone sits in the middle of the skull towards the front and forms the rear of the orbit. It has been described as resembling a butterfly due to its wing-like processes. The sphenoid bone is divided into several parts: the body of the bone, two greater wings, two lesser wings, and the pterygoid processes. Ethmoid Bone The ethmoid bone is a small bone that separates the nasal cavity from the brain. It is lightweight due to its spongy, air-filled construction and is located at the roof of the nose and between the two orbits.

These CNS neuroglia produce the myelin sheath around axons.

Oligodendrocytes

What part of the eye is considered the "blind spot"?

Optic disc

Jasmine is turning 18 and is getting ready to blow out her birthday candles. She closes her eyes and blows out her candles. What muscles in her face does she use to close her eyes and blow out her birthday candles?

Orbicularis Oris and oculi

Which muscle is at B? Orbicularis oculi m. Orbicularis oris m. Temporalis m. Frontalis m.

Orbicularis oculi m.

Check all that apply. Which of these muscles are wrist and finger flexors?

Palmaris longus m. Pronator teres m. Flexor carpi radialis m. Flexor digitorum superficialis m.

This branch of the ANS is commonly referred to as the rest and digest system.

Parasympathetic nervous system (PSNS)

What are the the two subsystems of autonomic nervous system?

Parasympathetic nervous system and sympathetic nervous system

When you tiptoe, the movement in the leg is called:

Plantar flexion

What type of action involves pulling the foot downward, away from the leg?

Plantarflexion

What is the muscle at A? Trapezius m. Platysma m. Levator scapulae m. Sternocleidomastoid m.

Platysma m.

Name the condition that causes hearing loss with age.

Presbycusis

If you are playing the piano, what position is your forearm in?

Pronation

If you hug someone, what kind of action is this?

Protracting scapula

External intercostal mm. origin and insertion?

RIBS

Which side of the body has a superficial view of the muscles?

RIGHT

Which photoreceptor is responsible for night vision?

RODS

Which muscle is shown at B?

Rhomboideus m.

Which of the following is NOT a glial cell of the central nervous system?

Satellite cell

These neuroglia of the PNS surround bundles of cell bodies (called ganglia).

Satellite cells

These neuroglia contribute to the myelination of the axons in the PNS.

Schwann cells

Which muscle is shown in the image?

Serratus anterior m.

These are all golden rules of skeletal muscle activity EXCEPT:

Skeletal muscles can only push.

The part of the PNS that is responsible for skeletal muscle and voluntary movement.

Somatic nervous system

4.Pronation-Maintaining anatomical position, when the forearm is positioned with the palms facing down, the forearm is in a prone position. A way to remember that is that you play piano in the prone position. 5. Elevation and Depression-A body part such as the scapula can be moved upward in a superior direction through elevation. The trapezius elevates the apex of the shoulder. By contrast, depression is moving the body part in an inferior direction.

Specialized Movements in the Lower Body 1. Dorsiflexion-Pulling the foot toward the leg. 2.Plantarflexion-Pulling the foot downward, away from the leg. 3. Inversion-Tilting the sole inward. The dotted silhouette represents the original position of the foot. A sprained ankle is a common injury when the foot is inverted too much. Most ankle injuries are inversion injuries. 4. Eversion-Tilting the sole outward. The dotted silhouette represents the original position of the foot.

Which type of nerves carry signals to the brain?

Spinal nerves

Which muscle is shown at C? (spine skeletal)

Spinalis m.

Name the three parts of the frontal bone.

Squamous, orbital, and nasal

What is the origin of the muscle at B? houlder Sternum and clavicle Top of head Spine

Sternum and clavicle

Which eye muscle is controlled by trochlear nerve?

Superior oblique

If you are holding soup, what position is your forearm in?

Supination

What is the anatomical movement when the forearm is positioned with the palms facing up?

Supine

Frontal Bone The frontal bone is located in the front of the skull and is divided into three parts: Squamous: Forms the main region of the forehead Orbital: Lies inferiorly and forms the superior border of the orbit Nasal: A smaller piece that articulates with the nasal bones and maxilla to contribute to the roof of the nose Sutures and processes of the skull: sphenoid, coronal, sagittal, lambdoid, lateral, occipital, mastoid, and styloid Viscerocranium The facial bones form the lower anterior regions of the skull and include the mandible, which is involved with the only truly motile joint found in the skull. The facial skeleton contains the vomer, two nasal conchae, two nasal bones, two maxilla, the mandible, two palatine bones, two zygomatic bones, and two lacrimal bones.

Sutures are immovable joints—the most notable sutures being between the cranial bones. Different cranial bones articulate to form the suture. Several sutures separate the parietal bone from neighboring cranial bones. The two parietal bones come together to form the sagittal suture. The parietal and frontal bones come together to form the coronal suture. The squamosal suture separates the parietal and temporal bones. Two sutures separate the occipital bone from neighboring cranial bones. Lambdoidal suture is distinguished by a heavily serrated-shaped line that separates the occipital bone from the parietal bones. Occipitomastoid suture is a small suture that separates the occipital bone from the temporal bones. A baby's head is usually the largest part of the body that must pass through the birth canal. Fortunately, newborns have soft spots in the skull that allow for the head to squeeze through the birth canal. These soft spots in the baby's head are called fontanelles. If you look at the top of a baby's head, you may see a pulsating action that seems to echo the heartbeat. The precise cause of this is unknown, but it is perfectly normal. This is how the soft spot got its name. Fontanelle means "little fountain."

Which part of the nervous system is active when you are running from a bear?

Sympathetic

The branch of the ANS that is commonly referred to as the fight-or-flight system.

Sympathetic nervous system (SNS)

Where are neurons able to communicate with other cells at special locations?

Synapse

This is where a presynaptic neuron communicates with a postsynaptic neuron.

Synapses

The insertion of the muscle at D. Base of hand Radius Thumb Index finger

THUMB

The pectoralis minor m. and the serratus anterior m. are both involved in the protraction of the scapula.

TRUE

Rhabdomyolysis Rhabdomyolysis occurs due to a muscle injury. The death of the muscular tissue into the bloodstream can cause kidney failure. If the kidneys cannot function, then waste and urine cannot be removed effectively. As a result, rhabdomyolysis can be life-threatening. With early diagnosis, patients can receive treatment with adequate hydration through IV fluids. Dialysis treatment could be used to help the kidneys function. Causes of Rhabdomyolysis: -A traumatic injury such as a car accident -Prolonged muscle compression -Traumatic electric shocks or burns -Venomous bites "Classic Triad" Symptoms: -Muscle pain -Muscle weakness (difficulty moving limbs) -Very dark urine; very little urine

Tendons, Aponeurosis, and Fascia The muscular and skeletal systems work together to form movement. The two systems are able to work together because muscles are attached to the bones, other tissues, and skin. Muscles connect to bones by tendons, which are made up of fibrous connective tissue. An aponeurosis is a pearly sheet-like layer, and it takes the place of the tendon in flatter muscles, like the abdominal muscles. The sheet-like fascia, similar to the appearance of a spider's web, is a type of dense regular connective tissue that encloses and separates muscles from one another. Just as the people in the body of Christ in the Church have different roles and specialized functions, the different parts of the body have different roles and specialized functions. If a tendon is injured, this could prevent movement entirely, even if the muscle is healthy and intact. A tendon is made up of fibrous connective tissue that connects muscle to bone. The cord-like tendon is capable of withstanding tension. At either end of the tendon, its fibers intertwine with the fascia of a muscle or the periosteum (a dense fibrous covering of a bone), allowing the force to be dissipated across the bone or muscle. The Achilles tendon, the thickest and strongest tendon in the body, is seen below. The Achilles tendon provides stability and limits the range of motion at the ankle joint. In some cases, muscles attach to an aponeurosis. An aponeurosis is also a sheet-like layer, and it takes the place of the tendon in flatter muscles, like the abdominal muscles. An aponeurosis can also attach to the bone, such as the scalp aponeuroses, and to the fascia in other muscles or tissues, such as the anterior abdominal aponeuroses. The large structure of the aponeurosis allows distribution over a wider area of muscles.

The pull exerted by a muscle is referred to as what?

Tension

Cerebellum and Brainstem The cerebellum is located under the cerebrum. It is primarily concerned with muscular coordination. Like the cerebrum, the cerebellum also has a thin layer of gray matter outside the white mater. The folds of gray matter in the cerebellum are referred to as folia. The white matter deep to this gray matter is called the arbor vitae, or tree of life. The brainstem includes the midbrain, the pons, and the medulla oblongata. The medulla oblongata contains many vital centers of the human body, like the cardiac center which controls heart rate. Cranial nerves III-XII (three through twelve) are all connected to the brainstem. The first two cranial nerves connect to the cerebrum.

The Cerebrum The cerebrum is the largest part of the human brain and is responsible for higher levels of mental processing. There are two cerebral hemispheres: right and left. Between these two hemispheres is a deep groove referred to as the longitudinal fissure. The two cerebral hemispheres are connected by a band of myelinated fibers called the corpus callosum. Each cerebral hemisphere is made up of four lobes: frontal, parietal, occipital, and temporal. Each lobe is associated with a specific function (e.g., the parietal lobe helps with interpreting touch, the occipital lobe is associated with vision, the temporal lobe plays a role in hearing, and the frontal lobe controls the skeletal muscle contraction). The outer layer of gray matter in the cerebrum is called the cerebral cortex. This thin layer contains about 70% of the 100 billion nerve cells in the human body. Deep to the cortex are long connecting myelinated axonal fibers contributing to the white matter of the cerebrum. The cerebral cortex contains many bumps or folds referred to as gyri (singular, gyrus). There are grooves between the gyri referred to as sulci (singular, sulcus).

Coupling Neuron Structure with Its Function Now that we understand the anatomy of the neuron and its three major components: the cell body (or soma), the dendrites, and the axon, let's briefly review the function of the neuron. The dendrites are specialized to receive electrical signals from other neurons or receptors (like tactile or touch receptors in the skin). Synapses, as previously reviewed, are the connections between a presynaptic neuron and a postsynaptic neuron (remember, there is a gap between these two neurons referred to as the synaptic cleft). After the dendrites have received information (e.g., a neurotransmitter released by the presynaptic neuron binds to a protein receptor in the cell membrane of the dendrite), ions (like potassium ions and sodium ions) may move in or out of the neuron. These ions are charged, resulting in an overall charge (called potential) forming in the cell body.

The axon hillock is a special region of the cell body that connects to the axon of the neuron. The axon hillock integrates these electrical changes, and this is the site where an action potential (an electrical signal) may or may not be generated. Action potentials are only carried down the axon of a neuron when a certain threshold (electrical charge) is reached at the axon hillock. If threshold is attained, the action potential propagates down the length of the axon to its end—the axon terminal. These axon terminals in turn synapse with other cells (like other neurons, muscle cells, or glands). Neurotransmitters will be released from the axon terminal once the action potential has reached this region of the axon. Some axons are covered with a fatty sheath called myelin, which helps to increase the speed of the propagation of the action potential down the length of the axon. Myelin is produced by certain neuroglial cells, and these will be discussed in more detail in the next lesson. If myelin is present on an axon, it does not completely cover the entire length of the axon (see image below). There are gaps between the myelinated segments called nodes of Ranvier. A myelinated axon will transmit an action potential more quickly compared to an unmyelinated axon.

Middle Ear The middle ear begins on the other side of the tympanic membrane. It is an air-fluid chamber that houses the auditory ossicles, eustachian tubes, and the oval window. There are muscles that attach the auditory ossicles to protect the inner ear. The eustachian tube is a tunnel that connects the middle ear to the nose and throat. The tube helps to drain fluid from the ear and equalize air pressure inside the head.

The ear is divided into three main parts: the outer, middle, and inner ear. The outer ear collects the sound waves and sends them to the middle ear. The middle ear transmits the sound waves and sends them to the inner ear where it processes the sound waves for transmission to the brain. The inner ear also plays a role in balance. Outer Ear The outer ear is comprised of the auricle, external auditory canal, tympanic membrane, and ceruminous glands. The auricle or pinna is the visible area of the ear located on the outside of the head. It is made of elastic cartilage. The shape of the auricle is created to collect sound waves from the external environment. Once collected, the sound waves travel through the opening in the ear called the external auditory canal. This tunnel contains hair and ceruminous glands. The ceruminous glands are responsible for producing cerumen (ear wax) that traps foreign objects, dust, and dirt and prevents them from getting into the ear. At the end of the external auditory canal is the tympanic membrane, commonly known as the ear drum. This thin, transparent sheet of tissue separates the outer ear from the middle ear and is responsible for transmitting sound vibrations from one section of the ear to the next.

The nervous system is the network of nerve cells (referred to as neurons). Neurons contain long fibers (also called axons) that transmit electrical signals between parts of the body. The neuron will be covered in more detail later. The components of the nervous system network include the brain, the spinal cord, and the peripheral nerves (divided into cranial nerves and spinal nerves). The nervous system is responsible for sensing information (e.g., visual information and touch) as well as controlling bodily functions (e.g., muscle contraction). Consider the role of the nervous system as you read the following passage of Scripture: Proverbs 4: A Father's Wise Instruction

The first paragraph of the passage expresses how Solomon remembers the teachings of his father, King David. Wisdom is defined as "the ability to use your knowledge and experience to make good decisions and judgments" ("Wisdom"). The crown sits on the skull, the home of the brain. The second paragraph of the passage highlights the difference between a righteous person and a wicked. Which individual would you assume to have more control over their nervous system? The third and final paragraph of this passage displays how the nervous system is connected to all areas of the body. Review this section, and note the many regions of the body controlled by the brain.

Actin and myosin are bound to one another. The myosin returns to a lower energy state. The myosin's movement is known as the "power stroke" as actin is pulled towards the M line, the sarcomere shortens, and the muscle contracts. If another ATP attaches to myosin, then myosin will release its cross-bridge with actin and return to the cocked state. The cycle can start over again to further contract the muscle. Without more ATP, the muscle would return to a relaxed state Tension is the pull exerted by a muscle. The amount of force created by tension can vary: this why we can move light objects differently than the way we move heavy objects. The amount of tension is dependent on the number of cross-bridges formed, which is influenced by the muscle fiber and frequency of neural stimulation.

The function of the muscle is for movement, the generation of heat, and maintaining body posture and position (which has been covered). Movement Muscle is a specialized soft tissue that produces tension to generate force. Elements of the muscle cell slide past one another to produce tension and change the shape of the muscle cell. When you flex your muscles, the muscle shape changes. Generating Heat Muscles contribute to homeostasis in maintaining body heat. Energy is required during muscle contraction, which produces heat as a byproduct. As a result, heat is generated throughout the entire body. When you exercise, you notice that your body temperature rises. If you are cold, you may have experienced shivering, where your muscles contract in various parts of your body to generate heat. The sheet-like fascia, similar to the appearance of a spider's web, is a type of dense regular connective tissue that attaches, stabilizes, encloses, and separates muscles. With fascia, muscles can attach directly to tissues. The skeletal muscles in the face that control expressions are attached directly to the fascia of the skin.

-The vastus lateralis m. is located on the lateral side of the femur. It is also located laterally to the rectus femoris m. Origin: Lateral surface of femur Insertion: Patella Action: Extends leg -Vastus intermedius m. is located deep to the rectus femoris m. On the left thigh, the recuts femoris m. is removed to reveal the vastus intermedius m. underneath. Origin: Anterior femur Insertion: Patella Action: Extends leg -Vastus medialis m. is located on the medial side of the femur. Origin: Medial surface of femur Insertion: Patella Action: Extends leg

The hamstring group consists of three muscles: the biceps femoris m., semimembranosus m., and the semitendinosus m. All of these muscles originate from the lower pelvis, the ischial tuberosity (the sitting bone). The semimembranosus and semitendinosus muscles insert into the tibia while the biceps femoris m. inserts into the fibula. All three muscles extend the thigh and flex the leg. -Biceps femoris m. is located laterally and posteriorly on the thigh. Origin: Ischial tuberosity Insertion: Fibula Action: Extends thigh; flexes leg -Semitendinosus m. is the superficial layer on top of semimembranosus m. Origin: Ischial tuberosity Insertion: Tibia Action: Extends thigh; flexes leg -Semimembranosus m. is the deeper layer underneath semitendinosus m. Origin: Ischial tuberosity Insertion: Tibia Action: Extends thigh; flexes leg

The muscles in the lateral rotator group, as the name suggests, act to laterally rotate the thigh at the hip. Take a look at the piriformis m. Piriformis: The piriformis is the most superior of the lateral rotator group muscles. Actions: Lateral rotation and abduction of the thigh at the hip. -Deep to the gluteal group is the piriformis m. Superior and laterally are the gluteus medius and gluteus minimus muscles. Superficially, the gluteus maximus m. is removed to reveal the piriformis m., a muscle used for lateral rotation. Origin: Sacrum Insertion: Femur Action: Laterally rotates the thigh In anatomy, the "thigh" is the region above the knee that does not encompass the hip group. The "leg" describes the area below the knee.

The muscles of the thigh consist of the quadriceps group, hamstring group, adductor group, and lateral rotator group. Quadriceps Group The front, fleshy part of the thigh is the quadriceps group. Quad (meaning "four"), consists of four main muscles: the rectus femoris m., vastus lateralis m., vastus medialis m., and the vastus intermedius m. We will include sartorius m. in this group as well, which is a long thin muscle that wraps from the lateral to the medial side of the quadriceps group. In this superficial view (no muscles removed), two muscles can be seen easily: sartorius m. and rectus femoris m. Both of these muscles flex the thigh. -With the most superficial muscles exposed, the sartorius m. can be seen on top of the quadriceps muscle group. The sartorius m. is the longest muscle in the human body. Origin: Anterior pelvis Insertion: Tibia Action: Flexes, abducts, and rotates thigh; flexes leg -The rectus femoris m. is one of the four muscles of the quadriceps femoris. Rectus femoris covers the other three deeper vastus muscles: vastus lateralis m., vastus intermedius m., and vastus medialis m. Origin: Anterior pelvis Insertion: Patella Action: Flexes thigh; extends leg -By removing the superficial muscles, sartorius m. and rectus femoris m., the deeper muscles are revealed: vastus lateralis m., vastus intermedius m., and vastus medialis m. All of these muscles insert into the patella and extend the leg.

Muscular System A muscle is an organ containing muscle fibers (cells), connective tissue, blood vessels, and nerves. Skeletal muscle is innervated by specific nerves and supplied with blood. Muscles use tremendous amounts of energy, so they must have an adequate blood supply for oxygen and the removal of wastes. Muscles share these properties: 1. Contractility: The ability of muscles to shorten 2. Excitability: The ability to respond to a neuron 3. Extensibility: The ability to be stretched 4. Elasticity: The ability to return back to the original shape

The muscular system is made of muscle tissue, which is composed of myocytes (muscle cells). The function of the muscular system is to maintain posture and control movement. The muscular system works with other body systems to carry out vital bodily processes. Perimysium is located around a fascicle (bundle) of fibers. Epimysium covers the entire skeletal muscle. Endomysium surrounds a single muscle fiber. The muscular system works with: Skeletal system: To maintain posture and control movement Cardiovascular system: Muscles in the heart contract for the heart to pump blood Digestive system: Smooth muscle in the digestive system allows peristalsis, letting food move through the digestive tract Nervous system: Muscles receive neural impulses from the brain that control muscle contractions Slow-twitch fibers are for activities that require long-term, repeated contractions (such as maintaining posture or running a marathon). The energy created for these muscles is done in the presence of oxygen (aerobic) to give a large amount of ATP slowly. Due to their large oxygen requirements, slow-twitch fibers are associated with a large number of blood vessels, mitochondria, and myoglobin. A large amount of myoglobin will give muscle its reddish color. The soleus is a muscle mainly composed of slow-twitch fibers because of its key role in standing

The enteric nervous system (ENS) controls the gastrointestinal system and is sometimes considered part of the autonomic nervous system. The ENS will affect the smooth muscle in the digestive system organs like the stomach and small intestine. This system is influenced by the ANS, but it can function independently of the ANS as well. It is often referred to as the "second brain."

The parasympathetic division of the ANS is more active when our bodies are more relaxed. In fact, a nickname for the parasympathetic nervous system is "rest-and-digest" since it helps slow the heart rate, bring down blood pressure, and support digestive activities (like the contraction of the smooth muscle in the wall of the stomach and intestines). The sympathetic nervous system often opposes the activities of the parasympathetic. It is responsible for more stimulating activities and is often given the nickname "fight-or-flight" since it will become more active when we need to run from danger. It is responsible for speeding up heart rate and increasing blood pressure. Digestion is much less supported when we are in a "fight-or-flight" scenario (this is why it is never wise to eat a meal if you are stressed or angry).

The retina, the inner layer, contains most of the nerves in the eyeball. It contains two layers: pigment and neural. The pigment layer absorbs light, and the neural layer prevents the light from bouncing. The retina also contains photoreceptors rods and cones. Cones are responsible for color vision. Rods are responsible for night vision. The macula is an area of the eye where there are no rods present. The macula has a large number of cones in the fovea centralis. There is one area of the eye called the optic disc which is considered the "blind spot." When light travels to this area, it is not able to be seen.

There are three layers that make up the eyeball: fibrous, vascular, and retina. The outermost layer is the fibrous layer, the middle layer is the vascular layer, and the innermost layer is the retina. Fibrous Layer The outer layer of the eyeball is made up of the sclera and cornea. The sclera is the white part of the eye. It is the attachment point for many extrinsic eye muscles. It is composed of collagen, elastic fibers, and blood vessels. The cornea is transparent and sometimes referred to as the "eye window," as it allows light to enter the eye. The cornea is composed of collagen but not blood vessels. Vascular Layer The middle layer of the eyeball is made up of the choroid, ciliary body, iris, and pupil. This layer is composed of a large number of blood vessels, lymphatic vessels, and eye muscles. The choroid supplies blood flow to the area between the sclera and the retina. The ciliary body contains fluid and muscles. The ciliary muscles help assist the pupil by changing its size when focusing on objects. The iris is the part of your eye that has color and surrounds the pupil. The color is related to the amount of melanin. The more melanin, the darker the eye color. There are two muscles surrounding the iris of the eye. The radial muscles open up the pupil and dilate while the circular muscle shrinks the pupil and constricts. The iris is also responsible for controlling the amount of light entering the pupil with both the circular and radial muscles. The pupil is the dark circle in the center of the iris, and it allows light to pass through to the retina.

What is the function of eyebrows?

They protect the eyes from liquids and cover from sunlight.

What type of potential is the minimum needed to produce an action potential?

Threshold

Propagation of action potential Propagation is the same event that repeats itself. Action potentials spread through the membrane by repeating action potential to the next membrane as the message is transmitted. Action potentials always move forward and never backward. Continuous transmission- This occurs when an unmyelinated axon produces an action potential then spreads to the next membrane. This reaction is slower. Saltatory transmission- This occurs when a myelinated axon produces an action potential, skips from node to node, and then moves to the next membrane. This causes a faster spread because of myelination. Myelination speeds up action potentials.

Transmission of action potential Chemical synapses rely on neurotransmitters to spread action potential to the next membrane. Once an action potential is received, it depolarizes down the axon and releases neurotransmitters from the presynaptic neuron. Once the neurotransmitter is released it must bind to the receptors to produce an action potential on the next membrane. Neurotransmitters are recycled to keep up with the demand and to prevent synapse fatigue. Synapse fatigue will weaken the synapse until the neurotransmitters have been recycled.

Muscles A, B, and C's functions are to extend the vertebral column, supporting posture.

True

Which part of the ear is known as the eardrum?

Tympanic membrane

.Fast-twitch fibers are for activities that require fast muscle contractions for a short duration (jumping or sprinting). Fast-twitch fibers rely on energy sources without oxygen (anaerobic) to receive the energy as quickly as possible. Lactic acid is a byproduct of anaerobic reactions in the muscles and is responsible for the stinging feeling in muscles when you are exercising. The lactic acid build-up will inhibit further energy from being given to the muscle in order to protect the muscle from over-exertion and damage. Fast-twitch fibers contain fewer blood vessels and mitochondria than slow-twitch fibers and less myoglobin, resulting in a paler color. Muscles that control eye movements contain many fast-twitch fibers.

Types of Muscular Tissue - Smooth muscle tissue occurs in the walls of internal organs, such as through the digestive tract. Smooth muscle is responsible for peristalsis, which aids the movement of food. Smooth muscle is involuntary and spindle-shaped. The nonstriated myocytes have a single, centrally-located nucleus. - Cardiac muscle tissue is only found in the heart. The heart contracts to pump blood throughout the body and to maintain blood pressure. Cardiac muscle is not consciously controlled—in other words, involuntary muscle. Cardiac myocytes are shorter than skeletal myocytes and only contain one or two centrally located nuclei. - Skeletal muscles are voluntary, even muscles relating to maintaining posture or balance. These muscles have myocytes that are elongated, tubular, and appear striated with multiple peripheral nuclei. Skeletal muscles attach to the skeletal system via tendons. Some skeletal muscles can attach directly to other muscles or to the skin, such as the muscles on the face that are responsible for facial expression.

repeated pattern of binding and releasing (the contraction and expansion) is between the two thin and thick strands of the sarcomere which results in muscle contraction. ATP (Adenosine Triphosphate) is the unit of energy that prepares myosin for binding and "recharges" the myosin. ATP binds to myosin and changes the angle of the myosin into a cocked position. The myosin is now ready to bind to actin. Calcium binds to troponin to expose the active-binding sites on actin. With the active-binding sites exposed, myosin is able to bind to actin forming a cross-bridge. What happens when there are injuries to the muscular system? What are some diseases of the muscular system? Muscular Dystrophy Muscular dystrophy can be caused by a defective dystrophin gene. The genetic disease causes: Muscle weakness Muscle proteins Death of the muscular tissue

Understanding the sarcomere structure will lead to improved knowledge of the sliding filament model. A sarcomere is defined as the segment between two neighboring, parallel Z-lines. Z-lines are made up of both actin myofilaments and the elastic protein titin, which is crosslinked by alpha-actinin. Actin attaches directly to the Z-lines while myosin attaches to the titin molecules. Next to the Z-line is the I-band, the region where actin myofilaments are not superimposed by myosin myofilaments. The I-band only has thin filaments. The I-band is spanned by the titin molecule connecting the Z-line with a myosin filament. The region between two neighboring, parallel I-bands is known as the A-band and contains the entire length of single myosin myofilaments. The A-band has both thick and thin filaments, and within the A-band, the H-band is only composed of thick filaments, which is the region not superimposed by actin myofilaments. In the middle of the H-band is the M-line, which is composed of myosin myofilaments and titin molecules crosslinked by myomesin. Myofilaments (Macromolecule) The thin filaments, actin, and the thick filaments, myosin, slide over one another, causing the sarcomere to appear shortened. The model of contraction for the interaction between actin and myosin is called the cross-bridge cycle.

Which of the following does NOT describe the smooth muscle?

Usually attached to skeleton

What muscle is located at letter B?

Vastus medius m.

Which cranial nerve is related to hearing?

Vestibulocochlear nerve

What is the function of intrinsic and extrinsic muscles in the back? Please respond in 1-2 complete sentences using your best grammar.

WRITE IN YOUR OWN WORDS FROM LESSON- Intrinsic back muscles support movement within the vertebral column. They are the deeper muscles in the back that have attachment sites to the spine. Posture and balance depend on these muscles and erect the spine. Hence, superficial erector spinae muscles include the iliocostalis m., longissimus m., and the spinalis m. "Extrinsic" means outward, which in this case, the most superficial back layers actually control upper limb movement.

List and briefly describe 3 vision defects.

WRITE IN YOUR OWN WORDS- Myopia- is known as being nearsighted. Hyperopia- is known as far-sightedness. Presbyopia- is known as being unable to "accommodate for focusing on objects in close proximity, which results in blurry vision with close images."

Divisions of the Nervous System There are two primary divisions within the Nervous System: central and peripheral. The central nervous system (CNS) is composed of the brain and spinal cord. The peripheral nervous system (PNS) includes the nerves which link the body to the brain and spinal cord. Functionally, there are two types of nerves in the PNS: sensory nerves and motor nerves.

Within the PNS, sensory receptors will pick up a variety of stimuli (e.g., visual signals or mechanical signals like touch) in our environment. This information is then sent to the CNS via sensory nerves. The spinal nerves carry these electrical signals to the spinal cord while the cranial nerves carry these signals directly to the brain. Ultimately, the brain receives all of the information and works to integrate and process these incoming signals. This information might elicit a response in the body (like the contraction of a muscle). In this case, motor nerves leaving the CNS bring electrical signals to the specific effector needed to carry out this response. The Motor division of the PNS is further subdivided into the autonomic nervous system (ANS) and the somatic nervous system. The autonomic nervous system works "automatically," or without our conscious effort. It controls those organs that we cannot voluntarily control, like the contraction of the heart (cardiac muscle) or contraction of the smooth muscle in the walls of blood vessels. The somatic nervous system controls those effector organs that we can voluntarily control. These organs include all of our skeletal muscles (e.g., biceps brachii and gluteus maximus). The autonomic nervous system controls many of the bodily processes that work to keep us alive and functional. The ANS affects heart rate, digestion, respiratory rate, salivation, perspiration, pupil diameter, urination, and sexual arousal. The ANS is classically divided into two subsystems: the parasympathetic nervous system and the sympathetic nervous system.

ewborns have five main cranial bones: two frontal bones, two parietal bones, and one occipital bone. At birth, the newborn has several fontanelles. These are the two notable fontanelles: a large, diamond-shaped frontal fontanelle and a smaller posterior fontanelle. The large, frontal fontanelle generally remains open until the child is about two years old. The posterior fontanelle closes during the first two to three months of an infant's life. Over a period of 18 to 24 months, cranial bones come together and the fontanelles close. This is called intramembranous ossification. The closings of the fontanelles eventually form the sutures of the neurocranium.

Zygomatic Bones The two zygomatic bones form the cheeks and contribute to the orbits. Lacrimal Bones The two lacrimal bones form the medial wall of the orbit. The lacrimal bones are the two smallest bones located in the face. Nasal Bones The bridge of the nose is made up of two slender nasal bones. The vomer forms the nasal septum at the base of the nasal cavity. The inferior nasal conchae are located within the nasal cavity. They are spongy and curled in shape; their primary function is to increase the surface area of the nasal cavity, which also increases the amount of air that contacts the mucous membranes and cilia of the nose, thus filtering, warming, and humidifying the air before it enters the lungs. Maxilla Bones The upper jaw is made up of the maxilla bones. They provide the bed for the upper teeth, the floor of the nose, and the base of the orbits. Palatine Bones The roof of the mouth, located at the back of the nasal cavity, is formed by the palatine bones. The Mandible Finally, the mandible forms the lower jaw of the skull. The joint allowing the jaw to move is known as the temporomandibular joint, which forms the only non-sutured joint in the skull.

What is the muscle at F? Orbicularis oris m. Zygomaticus m. Masseter m. Buccinator m

Zygomaticus m.

Muscles A, B, and C are part of what compartment?

anterior

Name the structure underneath the cerebrum.

cerebellum

Which muscle is located at J?

extensor digitorum m.

When actin and myosin are interlaced with each other and slide over each other, this is known as the sliding ______ model of contraction.

filament

Which muscle is located at letter A?

gracilis m.

The extensor pollicis indicis m. extends the _____ finger.

index

The thorax is considered in what region of the body?

neck and the abdomen

Which muscle is located at F?

palmaris longus m.

What is the insertion for muscles A, B, and C?

patella

What is the official name of the "6-pack abs"? (Leave out the word "muscle." You must spell correctly.)

rectus abdominis

Which neuron sends signals towards the Central Nervous System?

sensory

Which one of these muscle types is voluntary?

skeletal muscle

Which of the following is NOT one of the 3 muscle types?

straight

What connects muscle to bone?

tendon

Which muscle is located at letter C?

vastus lateralis m.