Skeletal and Muscle System Quiz

Skeletal System Functions

• The skeletal system provides support and shape to the body.
• Bones protect vital organs like the brain, heart, and lungs.
• Bones, along with skeletal muscles, allow for body movement.

Bone Classification

• Bones are classified by size and shape.
• Four main types: long (e.g., femur, humerus), short (e.g., wrists, ankles), flat (e.g., ribs, skull), and irregular (e.g., vertebrae).

Compact and Spongy Bone

• Compact bone forms the outer layer, providing strength and protection.
• Spongy bone has a honeycomb structure, containing bone marrow for blood cell production and mineral storage.

Long Bone Structure

• Diaphysis: The long shaft in the middle
• Epiphysis: The rounded ends
• Metaphysis: The area connecting the shaft to the ends
• Epiphyseal plate: The growth plate in children.

Osteoblasts and Osteoclasts

• Osteoblasts build new bone.
• Osteoclasts break down old bone.
• These processes work together to maintain and modify bone structure.

Axial Skeleton Bones and Landmarks

• Skull: frontal, parietal, occipital, temporal, sphenoid, ethmoid, landmarks: orbit, zygomatic, mandible
• Hyoid bone
• Vertebral Column: cervical (7), thoracic (12), lumbar (5), sacrum, coccyx, landmarks: vertebral body, spinous process, transverse process.
• Rib Cage: sternum (manubrium, body, xiphoid process), ribs (12 pairs).

Appendicular Skeleton Bones and Landmarks

• Pectoral Girdles: clavicle, scapula (acromion, spine, glenoid cavity)
• Upper Limbs: humerus (head, greater/lesser tubercles), radius, ulna, carpals, metacarpals, phalanges
• Pelvic Girdle: hip bones (ilium, ischium, pubis), sacrum, coccyx
• Lower Limbs: femur (head, greater/lesser trochanters), patella, tibia, fibula, tarsals, metatarsals, phalanges

Types of Joints and Movements

• Joint Types: fibrous (immovable), cartilaginous (semi-movable), synovial (freely movable)
• Movements: Hinge (elbow, knee), Ball-and-socket (shoulder, hip), Pivot (neck), Gliding (wrist, ankle)

Muscle Tissue Types

• Skeletal: striated, voluntary, attached to bones for movement
• Cardiac: striated, involuntary, found in heart walls, controls heartbeat
• Smooth: visceral, involuntary, found in internal organs (e.g., stomach, blood vessels).

Whole and Single Muscle Fiber Structures

• Whole muscle: epimysium (outer covering), fasciculi (bundles of muscle fibers), perimysium (covering fasciculi)
• Single muscle fiber: endomysium (innermost covering), myofibrils, sarcomeres (actin and myosin filaments).

Muscle Contraction Mechanisms

• The sliding filament mechanism involves calcium binding to troponin, exposing myosin binding sites on actin, myosin heads pulling actin filaments inward, shortening muscle fibers, and causing contraction.

Role of Calcium and ATP

• Calcium ions initiate contraction by binding to troponin, exposing myosin binding sites on actin.
• ATP provides the energy for myosin heads to bind to and pull actin filaments.

Muscle Responses

• Single fiber twitch: involves a brief contraction from one stimulus
• Single fiber tetanus: involves sustained contraction from rapid, repeated stimuli before relaxation.

Muscle Energy Sources

• ATP: immediate energy source
• Phosphocreatine: quick ATP replenishment
• Glucose breakdown: ATP supply with low oxygen.

Muscle Contraction Sequence

• Nerve signal triggers calcium release.
• Calcium allows myosin to bind to actin.
• Myosin pulls actin filaments inward, shortening the muscle fibers.
• Shortened overlapping fibers cause overall muscle contraction.

Defining Muscle Terms

• Origin: attachment point on stationary bone
• Insertion: attachment point on movable bone
• Belly: the fleshy, contracting part of the muscle.

Muscle Naming

• Based on location, shape, size, number of origins, action, or attachments.

Major Muscle Actions

• Major muscle actions: Deltoid (arm abduction/flexion), Biceps (elbow flexion), Triceps (elbow extension), Quadriceps (knee extension), Hamstrings (knee flexion), Gastrocnemius (plantar flexion), Abdominals (trunk flexion), Erector spinae (trunk extension).

Introduction to the Human Body

• Anatomy: the study of structure and shape of the body and its parts.
• Physiology: the study of how the body and its parts function.

Levels of Human Body Organization

• Atoms, molecules, organelles, cells, tissues, organs, organ systems, organism

Major Organ Systems (12)

• Integumentary (skin, hair, nails)
• Skeletal (bones, cartilage, ligaments)
• Muscular (skeletal, cardiac, smooth muscles)
• Nervous (brain, spinal cord, nerves)
• Endocrine (hormones)
• Cardiovascular (heart, blood vessels)
• Lymphatic (lymph nodes, vessels, tissues)
• Respiratory (nose, lungs, diaphragm)
• Digestive (mouth, stomach, intestines)
• Urinary (kidneys, bladder, urethra)
• Reproductive (ovaries, testes, uterus)
• Immune (white blood cells, lymph organs)

Homeostasis

• Homeostasis refers to maintenance of a relatively stable internal environment, important for proper cell and body function, despite external changes.

Anatomical Position

• Standard reference position for describing body structures, standing upright, feet flat apart, arms at the sides with palms facing forward. Eyes and toes pointing ahead.

Anatomical Planes

• Sagittal (divides into left and right sections), Coronal (divides front and back sections), Transverse (divides into upper and lower sections).

Anatomical Terms for Quadrants and Regions

• Quadrants (RUQ, LUQ, RLQ, LLQ)
• Regions (umbilical, hypogastric, epigastric, hypochondriac, lumbar, iliac)

Major Body Cavities

• Dorsal: cranial (brain), spinal (spinal cord).
• Ventral: thoracic (heart, lungs, related structures), abdominal (stomach, liver, gallbladder, spleen, most intestines, pancreas), pelvic (urinary bladder, internal reproductive organs, rectum).

Basic Chemistry Terms

• Matter: anything that occupies space and has mass.
• Element: a pure substance that cannot be broken down into simpler forms by chemical means.
• Atom: the fundamental unit of an element.
• Proton, neutron, electron: components of an atom (proton + and, neutron neutral, electron -).
• Ionic bond: electron transfer between atoms.
• Covalent bond: sharing of electrons between atoms.
• Hydrogen bond: weak attraction among molecules.

Electrolytes

• Ions (charged atoms or molecules) dissolved in water, such as cations (positive) and anions (negative).

Molecules vs Compounds

• Molecule: two or more atoms bonded together.
• Compound: two or more different elements chemically bonded together.

Water's Importance

• Medium for biochemical reactions, Transports nutrients and wastes, Lubricates joints, Regulates body temp, Maintains blood volume.

pH Scale

• A scale to measure acidity or basicity.
• Seven (7) is neutral.
• Below it is acidic, above basic.

Catalysts and Enzymes

• Catalyst: substance that speeds up a reaction without being consumed.
• Enzyme: biological catalyst (protein). Speed up reactions by lowering activation energy.

Differentiating Mixtures

• Mixture: two or more substances mixed but not chemically bound together, can be easily separated (e.g., salad, mixed nuts).
• Solution: one substance completely dissolved in another, forming a homogeneous mixture (e.g., sugar in water)
• Suspension: large particles, float in a liquid, settle out over time (e.g., muddy water)
• Colloidal suspension: small particles dispersed in a liquid, stays evenly dispersed (e.g., milk, fog)
• Precipitate: solid substance formed during a chemical reaction by combining two solutions (e.g., a solid forming at the bottom of two solutions when mixed).