Human Anatomy and Physiology Quiz

Skeletal System Functions

• The skeletal system provides support and shape to the body
• It protects vital organs like the brain, heart, and lungs.
• Bones and skeletal muscles enable body movement.

Bone Classification

• Bones are categorized by size and shape into four main types:
  • Long bones (e.g., femur, humerus) have a long cylindrical shaft.
  • Short bones (e.g., wrist and ankle bones) are roughly cube-shaped.
  • Flat bones (e.g., ribs, skull, shoulder blades) are thin and curved.
  • Irregular bones (e.g., vertebrae) have complex shapes that don't fit the other categories.

Compact and Spongy Bone

• Compact bone forms the outer layer and is dense and solid.
• Spongy bone is located within bones, with a porous, honeycomb structure. It contains bone marrow, which produces blood cells and stores minerals. Compact bone offers strength and protection.

Long Bone Structure

• Diaphysis: the long shaft in the center of the bone.
• Epiphysis: the rounded ends of the bone.
• Metaphysis: the area connecting the diaphysis to the epiphysis.
• Epiphyseal plate: the growth plate in children located between the epiphysis and metaphysis.

Osteoblast and Osteoclast Roles

• Osteoblasts build new bone.
• Osteoclasts break down old bone.
• These processes are vital for bone growth in both length and width.

Axial Skeleton Bones

• Skull: frontal, parietal, occipital, temporal, sphenoid, ethmoid.
• Hyoid bone.
• Vertebral Column: cervical, thoracic, lumbar, sacrum, coccyx.
• Rib Cage: sternum (manubrium, body, xiphoid process), ribs.

Appendicular Skeleton Bones

• Pectoral Girdles: clavicle, scapula.
• Upper Limbs: humerus, radius, ulna, carpals, metacarpals, phalanges.
• Pelvic Girdle: hip bones (ilium, ischium, pubis), sacrum, coccyx.
• Lower Limbs: femur, patella, tibia, fibula, tarsals, metatarsals, phalanges.

Joint Types & Movement

• Fibrous joints: immovable, rigid
• Cartilaginous joints: semi-movable, rigid
• Synovial joints: freely movable
• Common movements include hinge, ball-and-socket, pivot, and gliding.

Muscle Tissue Types

• Skeletal muscle: striated, voluntary, attached to bones.
• Cardiac muscle: striated, involuntary, found in the heart.
• Smooth muscle: visceral, involuntary, found in internal organs.

Whole Muscle Structure

• Epimysium: outer covering of a whole muscle
• Fasciculi: bundles of muscle fibers
• Perimysium: covers fasciculi
• Muscle Fiber Structure/Single Muscle fiber
• Endomysium: innermost covering of a muscle fiber
• Myofibrils: contractile units of a muscle fiber
• Sarcomeres: actin and myosin filaments within myofibrils

Muscle Contraction Mechanics

• Sliding filament mechanism describes the process where calcium initiates muscle contraction by binding to troponin and exposes myosin binding sites on actin; ATP provides energy for myosin to pull the actin filaments inwards, generating the contraction.

Muscle Terminology & Naming

• Origin: attachment point on stationary bone.
• Insertion: attachment point on movable bone.
• Belly: fleshy, contracting part of the muscle.
• Naming basis: location, shape, size, number of origins, action, or attachments (e.g., biceps, rectus, deltoid).

Major Muscle Actions

• Deltoid: abduction/flexion of the arm.
• Biceps: flexion of the elbow.
• Triceps: extension of the elbow.
• Quadriceps: knee extension.
• Hamstrings: knee flexion.
• Gastrocnemius: plantar flexion (pointing toes).
• Abdominals: trunk flexion.
• Erector spinae: trunk extension.

Human Body Organization

• Organization of the human body begins at smallest to largest.
  • Atoms
  • Molecules
  • Organelles
  • Cells
  • Tissues
  • Organs
  • Organ Systems
  • Organism

Organ Systems in Human Body

• Integumentary (skin, hair, nails)
• Skeletal (bones, cartilage, ligaments)
• Muscular (skeletal, cardiac, smooth muscles)
• Nervous (brain, spinal cord, nerves)
• Endocrine (hormones from glands like thyroid, pancreas)
• 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

• Maintaining a stable internal environment, overcoming external changes (temperature, pH, fluid balance, nutrients).

Anatomical Positions

• Standard reference position for describing body locations; standing upright, feet flat and slightly apart, arms at sides with palms facing forward, and head, eyes, and toes pointing straight ahead.

Anatomical Planes

• Sagittal: divides the body into right and left.
• Coronal (Frontal): divides the body into front and back.
• Transverse (Horizontal): divides the body into upper and lower.

Anatomical Directions and Relative Positions

• Superior/Inferior (above/below)
• Anterior/Posterior (front/back)
• Medial/Lateral (toward the midline/away from midline)
• Proximal/Distal (closer to/further from the origin)
• Superficial/Deep (closer to/further from the surface)

Anatomical Regions and Quadrants

• Anatomical terms for quadrants (RUQ, LUQ, RLQ, LLQ) and regions (e.g., umbilical, epigastric, hypochondriac) are used to locate specific body areas for medical purposes.

Body Cavities

• Dorsal: Cranial (brain); spinal (spinal cord)
• Ventral: Thoracic (heart, lungs); Abdominal (stomach, liver, intestines); Pelvic (bladder, reproductive system)

Basic Chemistry Definitions

• Matter: anything that occupies space and has mass.
• Element: a pure substance that can't be broken down into simpler components chemically.
• Atom: the smallest unit of an element that still retains its properties.
• Four elements comprising 96% of body weight: Oxygen, Carbon, Hydrogen, Nitrogen.

Atomic Structure

• Protons (positive charge, in nucleus)
• Neutrons (no charge, in nucleus)
• Electrons (negative charge, orbit nucleus).

Chemical Bonds

• Ionic bonds: transfer of electrons (e.g., NaCl).
• Covalent bonds: sharing of electrons (e.g., H₂O).
• Hydrogen bonds: intermolecular attraction between molecules (not caused by electron transfer or sharing)

Ions and Electrolytes

• Ions: charged atoms or groups of atoms.
• Cations: positively charged
• Anions: negatively charged
• Electrolytes: form ions in aqueous solutions