Podcast
Questions and Answers
The sutures in your skull are an example of a synovial joint.
The sutures in your skull are an example of a synovial joint.
False
What type of muscle arrangement allows you to whistle?
What type of muscle arrangement allows you to whistle?
What term refers to a number of diseases that cause progressive loss of muscle mass and weakness?
What term refers to a number of diseases that cause progressive loss of muscle mass and weakness?
Muscular dystrophy
Genetic defects in dystrophin produce a disabling disease called _________.
Genetic defects in dystrophin produce a disabling disease called _________.
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What is the primary function of the masseter muscle?
What is the primary function of the masseter muscle?
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Match the following muscles with their corresponding actions:
Match the following muscles with their corresponding actions:
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What is the primary function of skeletal muscles?
What is the primary function of skeletal muscles?
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How do muscles attach to bones directly?
How do muscles attach to bones directly?
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Muscles can only pull and cannot push. True or False?
Muscles can only pull and cannot push. True or False?
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Hamstring muscles and quadriceps muscles form an antagonistic muscle pair. True or False?
Hamstring muscles and quadriceps muscles form an antagonistic muscle pair. True or False?
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What is excitability in muscle characterized by?
What is excitability in muscle characterized by?
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Name the five epidermal cell types found in the skin.
Name the five epidermal cell types found in the skin.
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Which layer of the epidermis has several layers of dead, scaly, keratinized cells?
Which layer of the epidermis has several layers of dead, scaly, keratinized cells?
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True or False: The dermis is composed mainly of collagen.
True or False: The dermis is composed mainly of collagen.
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What do myoepithelial cells do in sweat glands? They contract in response to sympathetic nervous system stimulation and squeeze _______ up the duct.
What do myoepithelial cells do in sweat glands? They contract in response to sympathetic nervous system stimulation and squeeze _______ up the duct.
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Match the following exocrine secretion modes with their descriptions:
Match the following exocrine secretion modes with their descriptions:
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What muscle protracts and stabilizes the scapula and assists in upward rotation?
What muscle protracts and stabilizes the scapula and assists in upward rotation?
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What muscle both flexes the forearm and the shoulder, and rotates (supinates) the hand?
What muscle both flexes the forearm and the shoulder, and rotates (supinates) the hand?
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_______ is responsible for extending the forearm.
_______ is responsible for extending the forearm.
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Match the muscle with its respective action:
Match the muscle with its respective action:
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What is the primary factor that determines the amount of tension generated by a muscle?
What is the primary factor that determines the amount of tension generated by a muscle?
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Cessation of nervous stimulation can lead to muscle relaxation.
Cessation of nervous stimulation can lead to muscle relaxation.
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What is the primary neurotransmitter involved in the neuromuscular junction for muscle contraction?
What is the primary neurotransmitter involved in the neuromuscular junction for muscle contraction?
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The ________ models muscle contraction as individual sarcomeres shortening.
The ________ models muscle contraction as individual sarcomeres shortening.
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Basal Cell Carcinoma arises from cells in which layer of the skin?
Basal Cell Carcinoma arises from cells in which layer of the skin?
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Squamous Cell Carcinoma is more dangerous than Basal Cell Carcinoma.
Squamous Cell Carcinoma is more dangerous than Basal Cell Carcinoma.
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What does the NS maintain to ensure that resting muscles are near the correct length?
What does the NS maintain to ensure that resting muscles are near the correct length?
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What is the most common type of skin cancer?
What is the most common type of skin cancer?
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Melanoma arises from which type of skin cells?
Melanoma arises from which type of skin cells?
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What is the definition of Twitch?
What is the definition of Twitch?
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Match the bone cell with its description:
Match the bone cell with its description:
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Is the 'Length-Tension relationship' affected by the fatigue of muscles?
Is the 'Length-Tension relationship' affected by the fatigue of muscles?
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The 'ALL or NOTHING' theory of muscle contraction states that if the threshold stimulus of +30mV is not reached, no part of the fiber will ______.
The 'ALL or NOTHING' theory of muscle contraction states that if the threshold stimulus of +30mV is not reached, no part of the fiber will ______.
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Osteoblasts are bone resorbing cells.
Osteoblasts are bone resorbing cells.
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Which hormone is secreted by the parathyroid glands to raise blood calcium levels?
Which hormone is secreted by the parathyroid glands to raise blood calcium levels?
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Match the types of muscle contractions with their definitions:
Match the types of muscle contractions with their definitions:
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Parathyroid hormone is responsible for both bone resorption and bone deposition.
Parathyroid hormone is responsible for both bone resorption and bone deposition.
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What is the function of the axial skeleton?
What is the function of the axial skeleton?
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Stress fractures are caused by abnormal ______ to a bone.
Stress fractures are caused by abnormal ______ to a bone.
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During aerobic exercises, which metabolic system is primarily used?
During aerobic exercises, which metabolic system is primarily used?
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Match the following types of exercises with their descriptions:
Match the following types of exercises with their descriptions:
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What system is mainly responsible for providing ATP during resistance (strength) training?
What system is mainly responsible for providing ATP during resistance (strength) training?
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What is the term for the maximum amount of oxygen an individual can use during intense exercise?
What is the term for the maximum amount of oxygen an individual can use during intense exercise?
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Muscle fatigue is the progressive weakness and loss of contractility from prolonged use of muscles. TRUE or FALSE?
Muscle fatigue is the progressive weakness and loss of contractility from prolonged use of muscles. TRUE or FALSE?
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What is the shape of smooth muscle myocytes?
What is the shape of smooth muscle myocytes?
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Which structure controls the size of the pupil?
Which structure controls the size of the pupil?
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Smooth muscle lacks striations.
Smooth muscle lacks striations.
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Smooth muscle regenerates well by __________.
Smooth muscle regenerates well by __________.
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Match the following muscle types with their characteristics:
Match the following muscle types with their characteristics:
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Study Notes
The Integumentary System
- The integumentary system consists of skin and its accessory structures, including hair, nails, and glands.
- Functions of the skin:
- Protection
- Regulation of body temperature
- Sensation
- Excretion
- Immune function
Epidermis
- The epidermis is the outermost layer of the skin.
- Five types of epidermal cells:
- Stem cells: undifferentiated cells that give rise to keratinocytes.
- Keratinocytes: majority of epidermal cells, synthesize keratin.
- Melanocytes: produce melanin, shields DNA from ultraviolet radiation.
- Tactile cells: touch receptor cells associated with dermal nerve fibers.
- Dendritic cells: macrophages that guard against pathogens.
Layers of the Epidermis
- Thin skin contains four layers, while thick skin contains five.
- Stratum corneum: outermost layer, several layers of dead, scaly, keratinized cells.
- Stratum lucidum: found only in thick skin, pale layer with eleidin protein.
- Stratum granulosum: three to five layers of flat keratinocytes with keratohyalin granules.
- Stratum spinosum: several layers of keratinocytes joined by desmosomes and tight junctions.
- Stratum basale: deepest layer, single layer of stem cells and keratinocytes.
The Life History of a Keratinocyte
- Keratinocytes are produced by mitosis in the stratum basale.
- New keratinocytes push older ones towards the surface.
- Cells undergo differentiation, keratinization, and eventually die.
Dermis
- The dermis is the layer beneath the epidermis.
- Ranges in thickness from 0.2 mm to 4 mm.
- Composed mainly of collagen, well supplied with blood vessels, sweat glands, sebaceous glands, and nerve endings.
- Houses hair follicles and nail roots.
- Muscles of facial expression attach to the dermis.
Hypodermis
- The hypodermis is the subcutaneous tissue.
- Contains more areolar and adipose tissue than the dermis.
- Pads the body and binds skin to underlying tissues.
- Common site of drug injection due to many blood vessels.
Skin Color
- Dark and light-skinned individuals have the same number of melanocytes, but different types of melanin.
- Eumelanin: brown/black pigment, more prevalent in dark skin.
- Pheomelanin: red and blond pigment, more prevalent in light skin.
- UV light exposure stimulates melanin secretion and darkens skin.
- Other pigments that influence skin color:
- Hemoglobin: adds reddish to pinkish hue.
- Carotene: yellow pigment acquired from diet.
Hair
- Three types of hair:
- Lanugo: fine, downy hair that appears on the fetus.
- Vellus: fine, pale hair that replaces lanugo by birth.
- Terminal: longer, coarser, and more heavily pigmented.
- Structure of hair:
- Medulla: core of loosely arranged cells and air spaces.
- Cortex: constitutes bulk of the hair, consists of several layers of elongated keratinized cells.
- Cuticle: composed of multiple layers of very thin, scaly cells.
Nails
- Anatomy of a fingernail:
- Nail plate: visible portion of the nail.
- Nail fold: area of skin surrounding the nail plate.
- Nail groove: groove on the underside of the nail plate.
- Nail bed: area beneath the nail plate.
- Nail matrix: area beneath the cuticle, where nail growth occurs.
- Hyponychium: area between the nail plate and the nail bed.
Glands
- Three modes of exocrine secretion:
- Merocrine: sweat glands and pancreas.
- Apocrine: apocrine sweat glands.
- Holocrine: sebaceous glands.
- Types of glands:
- Sweat glands: apocrine and eccrine.
- Sebaceous glands: holocrine, produce sebum.
- Ceruminous glands: apocrine, produce cerumen (earwax).
- Mammary glands: modified apocrine glands, produce milk.
Functions of Hair
- Depends on body region and type of hair.
- Alerts us to parasites crawling on the skin.
- Hair on the scalp, trunk, and limbs provides warmth and protection.
- Eyelashes and eyebrows protect the eyes.
Skin Markings
- Colors of diagnostic value:
- Cyanosis: blueness due to oxygen deficiency.
- Erythema: redness due to increased blood flow.
- Pallor: paleness due to decreased blood flow.
- Albinism: white skin due to genetic lack of melanin.
- Jaundice: yellowing due to bilirubin in the blood.
- Hematoma: bruising.
Cancer and Skin
- Types of skin cancer:
- Basal cell carcinoma: least dangerous, seldom metastasizes.
- Squamous cell carcinoma: more aggressive, can metastasize.
- Melanoma: most aggressive, can be fatal if not treated early.
Please let me know if you need any further assistance.### Joints and Their Classification
- A joint is any point where two bones meet, whether or not the bones are movable at that interface.
- Joint names are typically derived from the names of the bones involved (e.g., radioulnar joint).
- Joints can be classified according to the manner in which the bones are bound to each other (structure) or the degree of movement.
Classification of Joints by Structure
- Bony joints (synostosis): immobile joint formed when the gap between two bones ossifies, and the bones become, in effect, a single bone.
- Fibrous joints: join bones using fibrous connective tissue.
- Sutures: immobile or slightly mobile fibrous joints in which short collagen fibers bind the bones of the skull to each other.
- Gomphoses: attachment of a tooth to its socket, held in place by a fibrous periodontal ligament.
- Syndesmoses: fibrous joints at which two bones are bound by long collagen fibers.
- Cartilaginous joints: join bones using cartilage.
- Synchondroses: bones joined by hyaline cartilage, temporary joints in the epiphysial plates in children.
- Symphyses: two bones joined by fibrocartilage, allowing for slight movements.
Classification of Joints by Degree of Movement
- Synarthrosis: immobile joints.
- Amphiarthrosis: partially moveable joints.
- Diarthrosis: freely moveable joints.
Synovial Joints
- General anatomy: consisting of a joint capsule, articular cartilage, and synovial fluid.
- In a few synovial joints, fibrocartilage grows inward from the joint capsule.
- Examples of synovial joints include the temporomandibular joint, knee joint, and shoulder joint.
Lever Systems
- Long bones act as levers to enhance the speed or power of limb movements.
- Types of levers:
- First-class lever: has the fulcrum in the middle between effort and resistance.
- Second-class lever: has the resistance between the fulcrum and effort.
- Third-class lever: has the effort between the resistance and the fulcrum.
Range of Motion
- Range of motion (ROM): the degrees through which a joint can move.
- An aspect of joint performance and physical assessment of a patient's joint flexibility.
Axes of Rotation
- A moving bone has a relatively stationary axis of rotation that passes through the bone in a direction perpendicular to the plane of movement.
- Multiaxial joint: has three degrees of freedom or axes of rotation.
Muscular System
- Muscles are classified as skeletal, cardiac, or smooth.
- Skeletal muscles are voluntary, striated, and under conscious control.
- Functions of muscles:
- Movement
- Stability
- Control of openings and passageways
- Heat production
- Glucose storage
Muscle Compartment
- Intermuscular septa: thick fascia that separate one compartment from another.
- Muscle compartment contains nerves, blood vessels, and stretch receptors.
Fascia
- Fibrous connective tissue that is found below the skin.
- Classified as superficial, deep, visceral, or parietal.
Strength of a Muscle
- Determined partly by the orientation of its fascicles.
- Muscles come in different shapes, such as pennate, circular, and parallel.
Types of Muscle Arrangements
- Pennate: feather-shaped, with fascicles approaching the tendon from one side.
- Unipennate: fascicles approaching the tendon from both sides.
- Bipennate: fascicles approaching the tendon from one side and then dividing into two parts.
- Multipennate: bunches of feathers converging to a single point.
Muscle Attachment
- Direct manner: muscle attaches to bone directly.
- Indirect manner: muscle attaches to bone using a tendon or aponeurosis.
Muscle Movement
- Muscles work in antagonistic pairs to produce movement.
- Agonist: the muscle that provides the major force to complete the movement.
- Antagonist: the muscle that opposes the action of the prime mover.
Characteristics of Muscle
- Excitability: ability to respond to a stimulus.
- Contractility: ability to shorten when stimulated.
- Conductivity: ability to transmit electrical signals.
- Extensibility: ability to be stretched.
- Elasticity: ability to return to its original rest length after being stretched.
Muscle Fiber
- Multinucleated: formed from the fusion of embryonic myoblasts.
- Has a sarcolemma, sarcoplasm, and myofibrils.
- Myofibrils are composed of contractile proteins, such as actin and myosin.
Neuromuscular Junction
- Site where a motor neuron terminates and forms a synapse with a muscle fiber.
- Responsible for transmitting electrical signals from the neuron to the muscle fiber.### Muscle Striations and Their Molecular Basis
- Muscle striations result from the precise organization of myosin and actin in cardiac and skeletal muscle cells
- Striations are alternating A-bands (dark) and I-bands (light)
Sarcomere Structure
- A sarcomere is the functional contractile unit of a muscle fiber
- It is the segment from one Z disc to the next Z disc
- Contains thick filaments (myosin) and thin filaments (actin)
Thick Filaments (Myosin)
- Have a double globular head with a shaft-like tail
- Each head has an active site that can bind to actin subunits
- Have a bare zone with no heads in the middle
Thin Filaments (Actin)
- Consist of two intertwined strands (F-actin)
- Have tropomyosin molecules that block 6-7 active sites on each actin subunit
- Ca-binding protein on each tropomyosin molecule
Titin (Elastic Filament)
- A giant, springy protein that interconnects thick filaments with the Z-line
- Helps stabilize and position thick filaments, preventing overstretching and providing recoil
Muscle Diseases
- Muscular dystrophy: a number of diseases that cause progressive loss of muscle mass, resulting in weakness and sometimes loss of mobility
- Genetic defects in dystrophin produce disabling disease muscular dystrophy
Muscle Functions
- Different muscle groups have specific functions, such as blinking, closing lips, elevating the mandible, flexing the forearm, and rotating the arm
Muscle Terminology
- Study aid to help with learning muscle names
- Includes muscles such as orbicularis oculi, obicularis oris, masseter, sternocleidomastoid, temporalis, and many others
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Description
This quiz covers the basics of the integumentary system, including the structure and function of skin, epidermis, dermis, and hypodermis, as well as accessory structures such as hair, nails, and glands.
