Biological Organization, Tissues, and Cell Modifications

Flashcards covering the components of the compound microscope, the hierarchy of biological organization, the four main types of animal tissues, and various cell modifications.

Compound Microscope

An optical instrument used for viewing small objects, containing parts such as the eye piece, objective, condenser, and mirror.

Biological Organization

The hierarchy of complex biological structures from the simplest to most complex: atom, molecule, cell organelles, cell, tissue, organ, organ system, organism, population, biocenoses, ecosystem, and biosphere.

Tissue

A group of similar cells that group together to perform a common function, serving as the fundamental unit that determines the nature of organs.

Epithelial Tissue

A tissue consisting of tightly packed cells that form a continuous layer to cover body surfaces, line cavities, and act as a barrier against pathogens and fluid loss.

Simple Squamous Epithelium

Flat, plate-like scale cells specialized for the exchange of materials through diffusion, commonly found in the lungs.

Simple Cuboidal Epithelium

Square-shaped cells in side view primarily involved in secretion, found in locations such as the kidney tubules.

Simple Columnar Epithelium

Rectangular, brick-shaped cells used for secretion and active absorption, found in the intestines.

Stratified Squamous Epithelium

A multi-layered tissue that regenerates quickly and provides protection, lining the esophagus.

Pseudostratified Ciliated Columnar

A specialized epithelial type found in the nasal passage.

Transitional Epithelium

A type of epithelium found in the urinary system.

Glandular Epithelium

Epithelium consisting of one or more cells that produce and secrete an aqueous fluid (secretion) usually containing proteins.

Connective Tissue

The most abundant and widely distributed tissue in complex animals, categorized into fibrous, supportive, and fluid types.

Fibrous Connective Tissue

Contains fibroblasts and a jelly-like matrix with white collagen fibers and yellow elastic fibers.

Cartilage

A supportive connective tissue made of collagenous fibers embedded in chondroitin sulfate; its cells, chondrocytes, secrete the matrix that provides a flexible cushion between bones.

Osteoblasts

Bone-forming cells that deposit collagen which, combined with calcium, magnesium, and phosphate ions, makes bone hard.

Blood

A fluid connective tissue consisting of plasma, Red Blood Cells (oxygen transport), White Blood Cells (defense), and platelets (clotting).

Skeletal Muscle

A voluntary muscle attached to the bone by tendons that creates movement through contraction.

Smooth Muscle

An involuntary muscle found in the walls of internal organs (intestine, stomach), blood vessels, and the iris of the eyes.

Cardiac Muscle

An involuntary muscle found only in the heart, responsible for pumping blood and possessing features of both skeletal and smooth muscle.

Neuron

A specialized signaling cell of the nervous tissue consisting of dendrites to receive impulses and an axon to transmit them to other neurons.

Neuroglia

Supporting cells found within nervous tissue that assist neurons.

Flagellum

A whiplike structure with an axoneme (nine fused pairs of microtubules surrounding two single microtubules) that propels a cell using dynein arms and $ATP$.

Cilia

Hairlike protrusions that can be motile (moving the cell or debris) or nonmotile (acting as mechanoreceptors, chemoreceptors, or photoreceptors).

Microvilli

Tiny finger-like structures that protrude from the cell membrane to allow for absorption, such as fat absorption via lymph vessels.

Pseudopodia

Temporary arm-like projections of eukaryotic cell membranes filled with cytoplasm and actin filaments, used for motility and ingestion in organisms like amoebas.