Human Anatomy: Bones of Hands and Feet

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Questions and Answers

What are the bones of the fingers and toes called?

Phalanges (correct)

Tarsals

Metatarsals

Carpals

What is the large hip bone called?

Ischium

Femur

Pelvis (correct)

Ilium

What is the medial bone of the leg?

Patella

Tibia (correct)

Humerus

Fibula

How many phalanges are in one foot?

14 Signup and view all the answers

What is the socket of the hip joint called?

Acetabulum Signup and view all the answers

What is the prominence just below the knee called?

Tibial tuberosity Signup and view all the answers

How many bones make up the skull?

22 Signup and view all the answers

What articulates with the tibia to form the knee joint?

Femur Signup and view all the answers

What is the tissue that connects a muscle to a bone?

Tendon Signup and view all the answers

What is the delay between the receiving of a nerve impulse and the beginning of the contraction called?

Latent period Signup and view all the answers

Which part of a twitch contraction usually involves the muscle getting shorter?

Contraction phase Signup and view all the answers

What is a jerky contraction in response to a single strong stimulus called?

Twitch contraction Signup and view all the answers

What is one motor neuron and all the skeletal muscle fibers it stimulates collectively called?

Motor unit Signup and view all the answers

What is the term for a contraction where there is partial or no relaxation?

Tetanic contraction Signup and view all the answers

What structure stores calcium needed for muscle contraction?

Sarcoplasmic reticulum Signup and view all the answers

What is the contraction where the tension on the muscle remains constant as the muscle shortens?

Isotonic contraction Signup and view all the answers

What is the condition characterized by decreased bone mass often due to low estrogen levels after menopause?

Osteoporosis Signup and view all the answers

What is the term for a break in a bone?

Fracture Signup and view all the answers

Which type of fracture extends all the way across the bone?

Transverse fracture Signup and view all the answers

What type of fracture occurs when the bone bends on one side and breaks on the opposite side?

Greenstick fracture Signup and view all the answers

What is the term for the realignment of broken ends of a bone?

Reduction Signup and view all the answers

What type of joint allows for free movement?

Synovial joint Signup and view all the answers

Which of the following is classified as an immovable joint?

Synarthrosis Signup and view all the answers

What is the primary tissue found between the surfaces of synarthrosis joints?

Fibrous connective tissue Signup and view all the answers

What is the primary function of the foramen in bone structure?

Allow passage of nerves and blood vessels Signup and view all the answers

How many bones comprise the appendicular skeleton?

126 Signup and view all the answers

Which structure on the scapula serves as an attachment point for muscles?

Coracoid process Signup and view all the answers

Which part of the femur articulates with the acetabulum?

Head of the femur Signup and view all the answers

What structural feature distinguishes the vertebral column's thoracic region?

Costal facets for rib articulation Signup and view all the answers

Which of the following bones is primarily involved in the formation of the eye orbit?

Zygomatic bone Signup and view all the answers

What is the total number of pairs of ribs in the human body?

12 Signup and view all the answers

Which bone structure provides a passageway for the carotid canal?

Temporal bone Signup and view all the answers

Which type of ossification occurs directly from mesenchymal tissue?

Intramembranous ossification Signup and view all the answers

What is a characteristic of diarthroses joints?

Presence of a joint capsule Signup and view all the answers

Which type of fracture is characterized by the bone breaking into multiple fragments?

Comminuted fracture Signup and view all the answers

What primarily influences long bone growth after the developmental stage?

Estrogen and testosterone Signup and view all the answers

Which joint type allows for movement around a single axis?

Hinge joint Signup and view all the answers

What is the primary function of osteoblasts in bone tissue?

Bone formation Signup and view all the answers

Which of the following processes involves a gradual replacement of cartilage by bone?

Endochondral ossification Signup and view all the answers

What is the role of bursae in synovial joints?

To reduce friction Signup and view all the answers

Which muscle is primarily responsible for elevating the mandible during chewing?

Masseter Signup and view all the answers

Which muscle is mainly responsible for flexing the forearm at the elbow?

Biceps brachii Signup and view all the answers

Which muscle acts as a primary mover for shoulder abduction?

Deltoid Signup and view all the answers

Which of the following muscles is classified within the hamstring group?

Semitendinosus Signup and view all the answers

Which abdominal muscle is situated on the outer layer?

External Oblique Signup and view all the answers

Which muscle is responsible for drawing the mouth upward as in smiling?

Zygomaticus Signup and view all the answers

What muscle pulls the upper lip upward and backward in sad facial expressions?

Mentalis Signup and view all the answers

Which major muscle is responsible for compressing the cheeks?

Buccinator Signup and view all the answers

Which muscle pulls the angles of the mouth laterally?

Risorius Signup and view all the answers

What muscle is primarily involved in frowning?

Depressor Anguli Oris Signup and view all the answers

Which muscle is responsible for drawing the lower lip downward?

Depressor Labii Inferioris Signup and view all the answers

Which muscle is involved in protruding the lower lip?

Mentalis Signup and view all the answers

Which cylindrical muscle extends up each side of the neck?

Sternocleidomastoid Signup and view all the answers

What are the last 5 pairs of ribs known as?

Floating ribs Signup and view all the answers

What is the organic part of bone matrix primarily composed of?

Collagen Signup and view all the answers

What type of ossification involves the conversion of mesenchyme in membranes to bone?

Intramembranous ossification Signup and view all the answers

What is the primary function of osteoclasts in bone tissue?

Resorbing old bone Signup and view all the answers

At what age does longitudinal growth typically end for males?

21 years Signup and view all the answers

What process primarily involves the conversion of hyaline cartilage into bone?

Endochondral ossification Signup and view all the answers

What is the primary function of the epiphyseal plates?

Allowing for longitudinal growth Signup and view all the answers

What is the term for the addition of new layers of bone on the surface throughout life?

Bone remodeling Signup and view all the answers

What is the large bone of the forehead?

Frontal bone Signup and view all the answers

Which bones form the top and upper sides of the cranium?

Parietal bones Signup and view all the answers

What is the name of the first cervical vertebra?

Atlas Signup and view all the answers

What is the term for the cavities that open into the nasal cavities?

Sinuses Signup and view all the answers

What is the ridge above the eye orbit called?

Superciliary arch Signup and view all the answers

What part of the temporal bone contains the ear bones (ossicles)?

Petrous part Signup and view all the answers

Which cranial bone contains the foramen magnum?

Occipital bone Signup and view all the answers

What is the opening in the occipital bone through which the spinal cord passes called?

Foramen magnum Signup and view all the answers

What is the term for the process of bone formation?

Ossification Signup and view all the answers

Which type of muscle tissue is responsible for involuntary movements?

Smooth muscle Signup and view all the answers

Which joint type is characterized by being entirely immovable?

Synarthroses Signup and view all the answers

What type of fracture is characterized by the bone being broken into multiple fragments?

Comminuted fracture Signup and view all the answers

At what age does longitudinal growth cease in females?

18 years Signup and view all the answers

Which of the following is a primary role of osteoclasts?

Bone resorption Signup and view all the answers

What is a characteristic feature of diarthroses joints?

They have a joint cavity Signup and view all the answers

What is the primary function of tendons?

Attach muscle to bone Signup and view all the answers

Study Notes

Bones of the Hands and Feet

The bones of the fingers and toes are called phalanges.
Each finger has three bones, except for the thumb, which has two.

The Pelvic Girdle

The large hip bone is called the os coxae.
The superior portion of the pelvic girdle is called the ilium.
The top of the hip is called the iliac crest.
The posterior portion of the hip bone where one sits is called the ischium.
The anterior portion of the pelvic girdle is called the pubis.
The socket of the hip joint is called the acetabulum.
The largest foramen in the body is the obturator foramen.

The Thigh

The large bone of the thigh is called the femur.
The portion of the femur that fits into the acetabulum (socket of the hip) is called the head of the femur.
The large, blunt processes on the proximal end of the femur are called trochanters.
The condyles of the femur articulate with the tibia, forming the knee joint.

The Lower Leg and Foot

The patella is the kneecap.
The medial bone of the leg is called the tibia.
The tibia articulates with the femur to form the knee joint.
The prominence just below the knee is called the tibial tuberosity.
The inner ankle is called the medial malleolus.
The smaller, lateral bone of the leg is called the fibula.
The short bones of the ankle are called tarsals.
The heel bone is called the calcaneus.
The Achilles tendon attaches to the heel bone.
The long bones of the foot are called metatarsals (five in total).
There are 28 phalanges in the feet.
Each great toe has two phalanges.
The other toes have three phalanges each.

The Axial Skeleton

The axial skeleton has 80 bones.
The skull comprises 28 bones.
The ears have six auditory ossicles.
There is only one hyoid bone.
The chest contains 25 bones (including the sternum and ribs).
Osteoporosis is the decreased bone mass often due to low estrogen levels after menopause.

Bone Fractures

A fracture is a break in a bone.
A complete fracture is a break that extends all the way across the bone.
A partial fracture is a break that extends part way across the bone.
A simple fracture is a break that only affects the bone itself.
A compound fracture is a break where the broken bone protrudes through the skin.
A displaced fracture means the broken ends are moved out of position.
Reduction is the realignment of the broken ends of a bone.
A greenstick fracture is a fracture where the bone bends on one side and breaks on the opposite side.
A comminuted fracture is a fracture where the bone is broken into several pieces.

Joints

Arthrology is the study of the joints of the body.
A joint (also called an articulation or arthrosis) is the site where two or more bones meet.
Synarthroses are immovable joints.
The tissue between the surfaces of synarthrosis joints is cartilage.
Synarthroses include cranial sutures and sternocostal joints.
Amphiarthroses are slightly movable joints.
Amphiarthroses include the pubic symphysis, sacroiliac articulation, and intervertebral joints.
Diarthroses are freely movable (synovial) joints.
The structures of diarthroses include:
- Articular cartilage covers the surfaces of the joint.
- The joint cavity is found between the articular surfaces.
- A joint capsule surrounds the surfaces.
- Synovial fluid lubricates the joint.
Examples of diarthroses include the shoulder, elbow, and wrist.

Movements at Joints

Gliding joints permit limited movement.
Hinge joints permit flexion and extension.
Pivot joints permit rotation.
Ball-and-Socket joints permit movement in all directions.

Muscles

Myology is the study of muscles.
Muscle fibers are the contractile structures within muscle cells.
Skeletal muscle is attached to bones and is responsible for movement.
Cardiac muscle is found only in the heart and pumps blood.
Smooth muscle is found in the walls of internal organs.
The roles of muscles include:
- Movement
- Production of heat
- Maintaining posture
- Stabilizing joints
Muscle fibers contract together in groups called fascicles.
The belly of a muscle is the thickest part.
Fascia is a sheet of connective tissue that surrounds muscle tissue.
Epimysium surrounds the entire muscle.
Perimysium surrounds fascicles.
A tendon is a tissue that connects a muscle to a bone.
An aponeurosis is a sheet of connective tissue that attaches a muscle to a bone.
Sarcoplasmic reticulum is a modified smooth ER that stores calcium.
Myofibrils are cylindrical organelles in muscle tissue.
A motor unit is made up of a single motor neuron and several muscle fibers.

Muscle Contraction

A motor neuron stimulates muscle fibers within a motor unit.
A motor unit is one motor neuron and all of the skeletal muscle fibers that it stimulates.
A twitch contraction is a jerky contraction in response to a single strong stimulus.
The latent period is the delay between the reception of a nerve impulse and the beginning of the contraction.
The contraction period is the part of the twitch contraction in which the muscle shortens.
The relaxation period is the part of the twitch contraction in which the muscle returns to its resting length.
Tonic contractions are responsible for posture and are a result of the alternating contraction of motor units in the muscles.
The refractory period of contraction is the time during which a muscle cannot respond to another stimulus.
Tetanic contractions occur when there is partial or no relaxation between stimuli.
Isotonic contractions are contractions where the tension on the muscle remains constant as the muscle shortens.
Isometric contractions are contractions where the muscle contracts but does not shorten.

Muscle Anatomy and Actions

The muscles deltoid and trapezius are named after their shapes.
The rectus abdominis is named for its location.
Origin is the point where a muscle is attached to a stationary bone.
Insertion is the point where a muscle is attached to a movable bone.
Sternocleidomastoid is a muscle named for its attachments.
External obliques are named for their directions.
Maximus or magnus are terms for large muscles.
Minimus is a term for small muscles.
Biceps and triceps are terms for muscles with two or three heads, respectively.
Internal obliques and external obliques are paired muscles.
Flexor refers to a muscle that produces flexion.
Flexion is the movement of a joint that decreases the angle between the bones.
Extension is the movement of a joint that increases the angle between the bones.
Abduction is the movement of a limb away from the midline of the body.
Adduction is the movement of a limb towards the midline of the body.
Supination is the movement of the palm of the hand so that it faces upwards.
Pronation is the movement of the palm of the hand so that it faces downwards.
Inversion is the movement of the sole of the foot so that it faces inwards.
Constriction is the narrowing of a structure.
Dilation is the widening of a structure.
Elevation is the movement of a structure upwards.
Depression is the movement of a structure downwards.
Circumduction is the movement of a limb in a circular motion.
Rotation is the movement of a structure around its axis.
Extensor refers to a muscle that produces extension.

Cranial Bones

There are eight cranial bones that protect the brain.
Frontal bone:
- Forms the forehead
- Contains the superior border of the eye orbit
- Possesses a ridge above the eye orbit called the supraorbital margin
- Has a flat portion between the eyebrows termed the glabella
Parietal bones: Form the top and upper sides of the cranium.
Temporal bones:
- Contain the ear canals
- The flat portion is called the temporal squama
- Another name for the ear canal is the external auditory meatus
- The mastoid process is found behind the ear lobe
- Contain the inner ear and ear bones (ossicles)
- The petrous portion houses these structures.
Sphenoid bone:
- Forms part of the anterior cranial floor and lateral eye orbits
- It resembles a bat shape.
- The sella turcica of the sphenoid bone houses the pituitary gland.
Ethmoid bone:
- Forms the superior nasal septum.
- The crista galli is a superior median ridge.
- The cribriform plate allows passage for the olfactory nerves.
Occipital bone:
- Contains the foramen magnum which is an opening for the passage of the spinal cord
- The external occipital protuberance is a tubercle on the posterior surface.
The occipital bone articulates with the 1st cervical vertebra, also known as the atlas.

The Ribs

True ribs:
- Also called vertebrosternal ribs.
- Connect directly to the sternum.
False ribs:
- Vertebrochondral ribs connect to the sternum indirectly through cartilage.
- There are 2 pairs (4) of floating ribs.

Bone Composition

Bones are made of both organic and inorganic materials.
- The organic part is called osteoid and provides flexibility.
- Hydroxyapatites (calcium salts) are the inorganic component, primarily made of calcium phosphate, which provides hardness.

Bone Cells

Osteoblasts are bone-depositing cells found in the periosteum and endosteum.
Osteoclasts are responsible for bone reabsorption, which is vital for repair and remodeling.
Osteocytes are mature bone cells embedded in bone tissue.

Bone Formation

Ossification, also known as osteogenesis, is the term for bone formation.
Intramembranous ossification: Takes place when mesenchyme in membranes transforms into bone, like in cranial bones.
Endochondral ossification: This process involves the conversion of hyaline cartilage into bone, forming most of the bones in the skeleton. It's how most bones develop.
Fontanels: The soft spots in a baby's skull where ossification is incomplete. They are typically filled with fibrous membranes.
There are six fontanels in a baby's skull.
These fontanels close by around 18 months of age and are replaced by sutures.

Bone Growth

Longitudinal growth: Occurs due to the division of chondrocytes within the epiphyseal plates. It ceases around age 18 for females and 21 for males.
Appositional growth: Involves the addition of new bone layers on the surface, continuing throughout life.
Estrogen and testosterone play a significant role in bone growth spurts due to the elongation of long bones.

Muscle Types

There are three primary types of muscle tissue:
- Skeletal muscle: Attached to bones, responsible for voluntary movement.
- Cardiac muscle: Found in the heart.
- Smooth muscle: Lines internal organs and blood vessels, and is responsible for involuntary movements.

Muscle Function

Muscles are vital for various bodily functions, including:
- Movement: Contracting muscles allow for locomotion.
- Heat production: Muscle contractions generate heat, particularly during shivering, a reflex for warmth.
- Maintaining posture: Muscles maintain body posture and stability.
- Stabilizing joints: Muscles help reinforce and stabilize joints.

Muscle Anatomy

Fascicles: Bundles of muscle fibers.
Belly: The fleshy portion of a muscle.
Fascia: Connective tissue that surrounds and compartmentalizes muscles.
Epimysium: Connective tissue covering the entire muscle.
Perimysium: Connective tissue surrounding fascicles.
Tendon: Connective tissue that attaches muscle to bone.
Aponeurosis: A broad, flat tendon.

Contraction Process

Sarcoplasmic reticulum: Plays a key role in muscle contraction by releasing and storing calcium ions.
Myofibrils: Contain the contractile proteins, actin and myosin.
Motor units: Consist of a single motor neuron and multiple muscle fibers that it innervates.
A motor unit is the smallest functional unit of contraction.
A single muscle fiber can only receive signals from a single motor neuron.
Muscle twitch: A single, brief contraction caused by a single nerve impulse.
Tetanic contractions: Repeated nerve impulses produce sustained contractions.
Isotonic contractions: Generate muscle tension while the muscle length changes.
Isometric contractions: Muscle tension increases without a change in muscle length.

Facial Muscles

Occipitofrontalis: Raises the eyebrows.
Masseter: Elevates the mandible (jaw).
Temporalis: Elevates and retracts the mandible.
Procerus: Depresses the medial portion of the eyebrows.
Nasalis: Compresses the nasal cartilages.
Orbicularis Oculi: Closes the eyelids.
Corrugator Supercilli: Draws the eyebrows medially.
Levator Palpebrae Superioris: Elevates the upper eyelid
Orbicularis Oris: Closes and protrudes the lips.
Levator Labii Superioris: Elevates the upper lip.
Zygomaticus Major: Elevates and retracts the upper lip, creating a smiling expression.
Zygomaticus Minor: Elevates the upper lip, potentially contributing to a sad expression.
Buccinator: Compresses cheeks.
Risorius: Draws the angles of the mouth laterally, similar to a smile or grin.
Depressor Anguli Oris: Draws the angles of the mouth downward, often associated with a frown or other negative expressions.
Depressor Labii Inferioris: Draws the lower lip downward.
Mentalis: Protrudes the lower lip.
Sternocleidomastoid: Extends up each side of the neck, a cylindrical muscle on each side.
Digastricus: Attaches to the hyoid bone.
Platysma: Extends from the clavicle, mandible, and lower lip. It contributes to an expression of horror or fright.

Chest and Back Muscles

Pectoralis Major: The large muscle on the anterior chest.
External Intercostals: Used for inhalation.
Internal Intercostals: Used for exhalation.
Latissimus Dorsi: Large muscle in the lower back, extends and adducts the arm.
Trapezius: Large muscle of the upper back, involved in shrugging the shoulders.

Abdominal Muscles

External Oblique: The outermost layer of the abdominal muscles, running diagonally.
Internal Oblique: The middle layer, also running diagonally, but in the opposite direction of the External Oblique.
Transversus Abdominis: The innermost layer, running horizontally.
Rectus Abdominis: The muscle between the pubis and xiphoid process.
Linea Alba: A fibrous band that runs down the midline of the abdomen, connecting the abdominal muscles.

Lower Back and Pelvic Muscles

Psoas Major: A powerful muscle that flexes and laterally rotates the thigh.
Diaphragm: The primary muscle of respiration, assisting in inhalation.

Shoulder and Arm Muscles

Deltoid: A triangular muscle that abducts the arm.
Teres Major: A muscle that helps internally rotate and adduct the arm.
Biceps Brachii: Located on the anterior arm, primarily responsible for flexing the forearm.
Coracobrachialis: Assists in flexing and adducting the arm.
Brachialis: Found in the anterior arm, assists in flexing the forearm.
Triceps Brachii: Located on the posterior arm, primarily responsible for extending the forearm.

Hand and Forearm Muscles

Flexor carpi ulnaris: Flexes and adducts the hand at the wrist.
Palmaris longus: Flexes the hand at the wrist.
Flexor digitorum superficialis: Flexes the middle phalanges of the fingers 2-5.
Brachioradialis: Flexes the forearm at the elbow.
Flexor carpi radialis: Flexes and abducts the hand at the wrist.
Pronator Teres: Pronates the forearm.
Supinator: Supinates the forearm.
Extensors: Muscles that extend the hand and wrist.
Extensor carpi ulnaris: Extends and adducts the hand at the wrist.

Leg Muscles

Sartorius: The longest muscle in the body, flexes and laterally rotates the thigh.
Quadriceps Femoris: Includes four muscles that extend the leg at the knee.
Adductor Longus: Adducts the thigh.
Adductor Magnus: Adducts and extends the thigh.
Gluteus Maximus: The largest muscle in the body, responsible for extending and externally rotating the thigh.
Hamstring muscles:
- Consist of three muscles:
  - Biceps femoris: Flexes the leg at the knee and extends the thigh.
  - Semitendinous: Extends the thigh and flexes the leg.
  - Semimembranous: Extends the thigh and flexes the leg.
Tibialis Anterior: Dorsiflexes and inverts the foot.
Gastrocnemius: A major calf muscle, plantarflexes the foot at the ankle and flexes the leg at the knee.
Soleus: Located deep to the gastrocnemius, a calf muscle responsible for plantarflexing the foot.

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Description

This quiz covers the bones of the hands and feet, including key structures such as phalanges and the pelvic girdle. Additionally, it explores the thigh bones and their important features. Test your knowledge of human anatomy with this focused quiz.