Science Olympiad: Anatomy

Support & Shape

The skeleton provides a solid framework that supports the body, maintaining posture and form by resisting gravity.

Protection

The skeletal system safeguards vital organs, such as the skull protecting the brain and the ribcage shielding the heart and lungs.

Movement

Bones serve as levers for muscles, facilitating complex actions like walking and running through an integrated system of joints.

Mineral Storage

Bones store essential minerals, primarily calcium and phosphorus, which are released into the bloodstream as needed.

Blood Cell Production

The bone marrow, particularly red bone marrow, produces red blood cells, white blood cells, and platelets.

Long Bones

Bones characterized by their length, such as the femur and humerus, designed for strength and movement.

Short Bones

Cube-shaped bones, like carpals and tarsals, providing stability and support with limited motion.

Flat Bones

Thin and curved bones, such as skull bones and ribs, offering protection for vital organs and support for muscle attachment.

Irregular Bones

Bones with complex shapes, such as vertebrae, providing protection and structural support.

Sesamoid Bones

Small, round bones within tendons, like the patella, helping to reduce friction and modify pressure during movement.

Osteoblasts

Specialized cells involved in bone formation, producing the bone matrix during ossification.

Osteocytes

Mature bone cells regulating mineral content and maintaining bone tissue within the bone matrix.

Osteoclasts

Large multinucleated cells responsible for bone resorption and maintaining calcium homeostasis.

Bone Lining Cells

Cells that cover the bone surface, regulating mineral exchange between bone and bloodstream.

Osteogenic Cells

Stem cells in the bone that give rise to osteoblasts, crucial for bone repair and regeneration.

Hyaline Cartilage

Flexible cartilage present in joints, nose, and trachea, allowing smooth movements at articulating surfaces.

Elastic Cartilage

More flexible than hyaline cartilage, found in the outer ear and epiglottis, providing shape maintenance.

Fibrocartilage

Tough cartilage found in intervertebral discs and knee joints, acting as a shock absorber.

Compact Bone

The dense outer layer of bone, providing strength and comprising about 80% of total bone mass.

Spongy Bone

Lightweight, porous bone housing red marrow for blood cell production, maintaining strength while reducing weight.

Ball-and-Socket Joints

Joints allowing the greatest range of motion, found in the shoulder and hip.

Hinge Joints

Joints that provide movement in one plane, like the elbow and knee.

Pivot Joints

Joints allowing rotational movement around a single axis, such as the neck.

Gliding Joints

Joints that allow slight movement in multiple directions, found in the wrist and ankle.

Skeletal Muscle

Voluntary, striated muscle attached to bones, capable of rapid contractions for movement.

Smooth Muscle

Involuntary, non-striated muscle found in visceral organs, controlling automatic processes.

Cardiac Muscle

Involuntary, striated muscle found only in the heart, responsible for pumping blood.

Excitability

The capacity of muscle tissue to respond to external stimuli, inducing contraction.

Contractility

The ability of muscle fibers to shorten and generate force for movement.

Extensibility

The ability of muscles to be stretched beyond their resting length.

Elasticity

The ability of muscles to return to their original shape after being stretched.

Sarcomeres

Fundamental contractile units of muscle fibers composed of actin and myosin.

Origin

The stationary attachment site of a muscle, generally closer to the body center.

Insertion

The movable attachment point of a muscle, located further from the center of the body.

Myosin heads and actin filaments

Components involved in the sliding filament model of muscle contraction.

Motor Units

Comprise a motor neuron and all the muscle fibers it innervates, critical for muscle contractions.

Exercise Benefits

Regular exercise strengthens muscles, enhances posture and balance, and improves overall physical performance.

Protection (Skin Function)

The skin acts as a barrier against pathogens, UV radiation, and physical injuries.

Temperature Regulation (Skin Function)

The integumentary system maintains optimal body temperature through sweating and blood vessel adjustments.

Sensation (Skin Function)

Contains sensory receptors perceiving touch, pressure, pain, and temperature information.

Excretion (Skin Function)

The skin helps remove waste products through perspiration.

Vitamin D Synthesis (Skin Function)

Skin cells produce vitamin D when exposed to sunlight, essential for calcium absorption.

Keratinocytes

Predominant epidermal cells providing a waterproof barrier.

Melanocytes

Cells producing melanin that determine skin color and protect against UV radiation.

Langerhans Cells

Cells vital for immune response, detecting pathogens entering through the skin.

Merkel Cells

Tactile sensors aiding in the sense of touch in the skin.

Dermis

Middle skin layer comprising connective tissue, blood vessels, and nerves.

Hypodermis

Subcutaneous layer containing fatty tissue for insulation and energy storage.

Skin Color Determination

Affected by melanin concentration, carotene, and hemoglobin.

Sebaceous Glands

Glands producing sebum that moisturizes and protects the skin.

Sweat Glands

Glands essential for thermoregulation and excretion through perspiration.

Ceruminous Glands

Glands in the ear canal producing earwax to protect against foreign particles.

Hair Functions

Protects scalp, aids in sensation, and provides insulation.

Nail Structure

Made of hardened keratin, protecting finger and toe tips and indicating overall health.