Bone Tissue Quiz

Groups of cartilage cells (chondrocytes) that originate from a single progenitor cell.

Part of the cartilage matrix, rich in proteoglycans, poor in collagen, surrounding isogenous cell groups.

Part of the cartilage matrix, with more collagen, less proteoglycans, in the spaces between isogenous cell groups.

Cartilage matrix containing abundant elastic fibers, providing flexibility.

Strong, elastic fibers enabling cartilage to stretch without breaking.

Combination of collagen (type I) and mineralized hydroxyapatite.

Cartilage matrix is arranged in different zones (superficial, transitional, radial, calcified) with different cell and fiber arrangements.

Predominant collagen type in cartilage matrix providing structural support.

Osteoblasts are found on bone surfaces, organized in layers like cuboidal or columnar cells.

Mature bone cells; maintain bone and connected to other cells via gap junctions.

Osteocytes live in small spaces (lacunae) within the calcified bone matrix.

Bone is mostly made of calcium hydroxyapatite crystals.

Bone stores calcium and helps maintain proper blood calcium levels.

Elongated, spindle-shaped cells that lack striations. They have a single, centrally placed nucleus and contract involuntarily.

Involves calcium ions (Ca2+) but the mechanism differs from striated muscle. It's slower and longer-lasting, controlled by the autonomic nervous system, hormones, and local conditions.

Small, dense structures within smooth muscle cells that act as anchoring points for actin filaments, allowing for contraction.

Invaginations of the smooth muscle cell membrane that are linked to the sarcoplasmic reticulum. They help regulate calcium levels for contraction.

Found in the walls of hollow organs like the digestive tract, blood vessels, and some reproductive and urinary structures.

Striated muscle found in the heart. Its cells are elongated, branched, and have a single nucleus. Contractions are involuntary, vigorous, and rhythmic.

Specialized junctions found between cardiac muscle cells that allow for efficient communication and coordinated contraction.

A network of collagen fibers that surrounds muscle cells and fascicles, providing support and structure.

The bone matrix is made up mostly of collagen (Type I), proteoglycans, and glycoproteins. These components play vital roles in providing structure, flexibility, and mineral binding.

Proteoglycans in bone consist of a core protein with attached side chains of glycosaminoglycans (GAGs), like chondroitin sulfate and keratan sulfate. These structures help to hold water and regulate bone's mechanical properties.

Glycoproteins, like osteonectin and osteopontin, aid in cell attachment to the bone's ground substance. They also influence mineralization, which means they help control how much calcium phosphate is deposited in the bone.

Osteocalcin is a bone-specific protein that binds calcium from the blood and stimulates bone remodeling, which involves breaking down old bone and replacing it with new bone.

BMPs, or bone morphogenetic proteins, are small regulatory proteins that play a crucial role in bone growth and development. They act as signaling molecules, controlling bone cell differentiation and formation.

Osteoclasts are large, multinucleated cells that break down bone tissue (resorption). They reside in Howship's lacunae, which are small pits or depressions in the bone surface.

Osteoblasts are bone-forming cells that synthesize and deposit new bone matrix. These cells can mature into osteocytes, which are embedded within the bone matrix.

The periosteum, a connective tissue layer surrounding bone, is divided into three distinct layers: an outer connective tissue layer, a middle layer rich in collagen fibers, and an inner layer containing osteoprogenitor cells.

Thin muscle fibers rich in myoglobin and mitochondria. They contract slowly due to low ATPase activity in their myosin. They are used for sustained effort, like maintaining posture.

Thick muscle fibers with less myoglobin and high ATPase activity in their myosin. They contract quickly and are used for short bursts of intense activity.

Red muscle fibers with many mitochondria, suited for both sustained and short intense contractions.

White muscle fibers with few mitochondria, specialized for rapid accelerations and short-lasting maximal contractions. They rely on anaerobic glycolysis for energy.

Specialized cardiac muscle fibers that are larger than cardiomyocytes and conduct electrical signals throughout the heart, ensuring coordinated contraction.

A hormone secreted by the heart's atria that helps lower blood pressure by reducing sodium and water reabsorption in the kidneys.

A network of specialized cardiac muscle fibers that transmit electrical signals throughout the heart, coordinating its rhythmic contractions.

Red blood cells are biconcave disks, meaning they are flattened and have a depressed center on both sides. This shape helps them efficiently carry oxygen and pass through narrow blood vessels.

Red blood cells are responsible for transporting oxygen from the lungs to the body's tissues and carbon dioxide from the tissues back to the lungs.

Red blood cells are typically 7.5-7.8 µm in diameter, which is about the size of a small bacterium. They are 2 µm thick at their thickest point and 1 µm at their thinnest point.

Red blood cells lack a nucleus in their mature form. They lose their nucleus during development to maximize space for carrying hemoglobin.

An individual is Rh-positive if their red blood cells have at least one of the three most common Rh antigens (C, D, or E).

An individual is Rh-negative if their red blood cells lack all three of the most common Rh antigens (C, D, and E).

Platelets are crucial for blood clotting. They stick to damaged blood vessels and form a plug to stop bleeding.

Platelets are not complete cells, but small fragments derived from the cytoplasm of giant cells called megakaryocytes found in the bone marrow.