OP4003:Body Systems

Flashcards for reviewing key concepts from the lecture on the human body and its systems, including homeostasis, tissue types, and the relevance of various systems to optometry.

What is homeostasis?

A dynamic condition where the body can regulate its internal environment through feedback systems to maintain equilibrium despite external variations.

What are the major components of the nervous system?

Central nervous system (brain, spinal cord) and peripheral nervous system (nerves).

What are the four main types of tissue?

Epithelial, connective, muscle, and nervous.

What is the primary function of the eye, and why is the nervous system relevant to Optometry?

To detect light and relay this information to the brain for us to see; the retina is part of the nervous system, and diseases of the nervous system can affect the visual system.

What is epithelial tissue?

Tightly packed cells that form continuous sheets, specialized for exchanging materials with the environment, and found on exposed surfaces, lining passageways, and in glands.

What are the main functions of epithelial tissue?

Protection, control of passage of substances, secretion, and sensory role.

Describe simple squamous epithelium.

Single layer of flat cells, tightly packed with a central nucleus, found in areas of wear and tear, and functions in rapid diffusion, exchange, filtration, and absorption.

Describe simple cuboidal epithelium.

Single layer of cuboidal cells that function in secretion and absorption, found in glands and their ducts.

Describe simple columnar epithelium.

Single layer of tall cells with a nucleus near the base, may have microvilli or cilia, and may have goblet cells for mucus secretion; functions in secretion, absorption, diffusion, and locomotion if cilia are present.

Describe stratified squamous epithelium.

Surface cells are squamous, basal cells are cuboidal or columnar; functions in protection against abrasion, dehydration, UV radiation, and invasion by foreign substances.

Distinguish between endocrine and exocrine glandular epithelium.

Endocrine glands secrete hormones into the bloodstream, while exocrine glands have ducts onto epithelial surfaces and produce mucous, wax, sweat, oil, milk, and digestive enzymes.

What are the three basic components of connective tissue?

Cells, ground substance, and fibers (collagen, elastic, reticular).

What are the roles of connective tissue?

Fill in gaps, connect body parts, secrete part of basement membrane, cushion, protect, insulate, provide structure, store energy, immune response, and transport fluids and nutrients.

Describe loose connective tissue: areolar.

Randomly arranged fibers (collagen/elastin/reticular), multiple cell types, fills spaces around most structures, and found in the subcutaneous layer of skin and mucous membranes.

Describe loose connective tissue: adipose.

Signet ring shaped cells with a droplet of triglyceride, cytoplasm & nucleus lie around the edge. Found in the subcutaneous layer of skin, around the heart & kidneys, around joints, in eye socket. Prevents heat loss, provides energy reserve, supports, and protects.

Describe dense connective tissue: regular.

Fibers (mostly collagen) are arranged in bundles and lie in parallel; very strong and pliable, found in tendons, ligaments, and muscle aponeuroses.

Describe dense connective tissue: irregular.

Bundles of collagen fibers with an irregular arrangement; allows tension in multiple directions, and forms membranous capsules around organs and fasciae around muscles.

Describe bone tissue.

ECM contains minerals (e.g. calcium phosphate) & collagen. Cells = osteocytes. Can be dense (compact); responsible for strength or spongy; contains trabeculae, spaces between filled with red bone marrow.

Describe blood tissue.

Liquid connective tissue. Ground substance: plasma. Cells: White blood cells (WBC), Red blood cells (RBC), Platelets. Roles: the transport of nutrients and waste