CELLS AND TISSUES

Vocabulary flashcards covering cell organelles, cell parts, epithelial tissues, connective tissues, cartilage, bone, muscle tissues, and neurons from the lecture notes.

Mitochondria

Double-membrane organelle where ATP is produced; the cell’s powerhouse with cristae inside the inner membrane.

Ribosome

Ribonucleoprotein particle that is the site of protein synthesis; consists of large and small subunits of rRNA and proteins.

Free Ribosome

Ribosome that is not attached to the endoplasmic reticulum; synthesizes cytosolic and organellar proteins.

Rough Endoplasmic Reticulum

Endoplasmic reticulum with attached ribosomes; synthesizes proteins for secretion or for membranes.

Smooth Endoplasmic Reticulum

Endoplasmic reticulum without ribosomes; synthesizes lipids, carbohydrates, detoxifies chemicals, and stores calcium.

Golgi Apparatus

Flattened membrane sacs that modify, package, and distribute proteins and lipids for secretion or internal use.

Secretory Vesicles

Membrane-bound vesicles that transport proteins to the plasma membrane for secretion or to organelles.

Plasma membrane

Lipid bilayer that forms the cell’s outer boundary; regulates entry/exit and participates in signaling and cell recognition.

Cytoplasm

Cell interior excluding the nucleus; contains cytosol and organelles and is the site of many metabolic processes.

Chromatin

DNA and associated proteins in the nucleus; condenses to form chromosomes during cell division.

Nuclear Envelope

Double membrane surrounding the nucleus with nuclear pores, separating nucleoplasm from cytoplasm.

Nucleolus

Dense region (Center) within the nucleus where rRNA synthesis and ribosome assembly begin.

Nuclear Pore

Channels in the nuclear envelope that regulate the passage of molecules between the nucleus and the cytoplasm.

Nucleoplasm

Fluid inside the nucleus containing chromatin and nucleolus.

Microvilli

Finger-like projections that increase the surface area of the cell surface for absorption.

Cilia

Hair-like extensions on the cell surface that move mucus or fluids; composed of microtubules.

Nucleus

Cell’s control center containing DNA; regulates gene expression and cell activities.

Lysosome

Organelle with digestive enzymes; digests waste, bacteria, and unwanted cellular components.

Phagocytic Vesicle

Vesicle formed by phagocytosis; fuses with lysosome to digest its contents.

Proteasome

Protein complex that degrades damaged or unneeded proteins via ubiquitin tagging.

Centrosome

Organizing center for microtubules near the nucleus; important for spindle formation in cell division.

Centrioles

Cylindrical structures within the centrosome that organize spindle fibers; basal bodies for cilia/flagella.

Peroxisome

Contains enzymes (e.g., catalase) that break down hydrogen peroxide and participate in lipid metabolism.

Cytoskeleton

Network of protein filaments (microfilaments, intermediate filaments, microtubules) that support the cell, hold organelles in place, and change shape

Flagellum (Flagella)

Long, whip-like extension that enables cell motility (e.g., sperm).

Goblet cell

Unicellular mucus-secreting gland cell found in the intestinal and respiratory epithelia.

Simple Squamous Epithelium

Single layer of flat cells; enables diffusion and filtration; common in vessels and alveoli.

Simple Cuboidal Epithelium

Single layer of cube-shaped cells; functions in secretion and absorption; lines kidney tubules and glands.

Simple Columnar Epithelium

Single layer of tall cells; functions in secretion and absorption; may have goblet cells or microvilli.

Stratified Squamous Epithelium

Multiple cell layers; protection; keratinized (skin) or nonkeratinized (mouth/esophagus).

Stratified Cuboidal Epithelium

Two or more cell layers somewhat cube shaped cells; ducts of glands and certain glands (e.g., ovarian).

Stratified Columnar Epithelium

Multiple cell layers with tall, thin cells; protection and secretion; found in ducts like mammary glands and parts of the larynx.

Pseudostratified Columnar Epithelium

Single layer with nuclei at various levels; often ciliated with goblet cells; lines respiratory passages.

Transitional Epithelium

Stratified epithelium that appears cuboidal when unstretched and squamous when stretched; lines urinary organs.

Areolar Connective Tissue

Loose connective tissue with a mesh of collagen and elastic fibers; supports and nourishes surrounding tissues.

Adipose Tissue

Loose connective tissue with adipocytes storing fat; provides insulation, cushioning, and energy storage.

Reticular Tissue

Loose connective tissue with a reticular fiber network; supports lymphatic and hemopoietic tissues.

Dense Regular Collagenous connective tissue

Dense connective tissue with collagen fibers aligned in the same direction; withstands pull in that direction (tendons, ligaments).

Dense Regular Elastic connective tissue

Dense tissue with parallel elastic fibers; allows stretch and recoil (vocal folds, spinal ligaments).

Dense Irregular Collagenous connective tissue

Dense tissue with collagen fibers in multiple directions; strong in many directions (dermis, organ capsules).

Dense Irregular Elastic connective tissue

Dense tissue with elastic fibers in multiple directions; provides multi-directional strength and elasticity (elastic arteries).

Hyaline Cartilage

Transparent cartilage with a firm, flexible matrix; supports growth and provides smooth articulating surfaces (ends of bones, trachea).

Fibrocartilage

Cartilage with many collagen fibers; very tough and resistant to pressure (intervertebral disks, pubic symphysis, knee disks).

Elastic Cartilage

Cartilage with elastic fibers; highly flexible (external ear, epiglottis, auditory tubes).

Spongy Bone

Trabecular bone with a lattice of bone spicules and spaces filled with marrow; lighter weight.”

Compact Bone

Dense bone with organized lamellae around central canals; strong structure for weight-bearing.”

Blood

Fluid connective tissue with cells (RBCs, WBCs, platelets) and a liquid matrix; transports substances and defends against disease.

Bone Marrow

Soft tissue within marrow cavities; red marrow forms blood cells; yellow marrow stores fat.

Skeletal Muscle

Voluntary, striated muscle tissue composed of long, multinucleated fibers that move the skeleton.

Cardiac Muscle

Involuntary, striated muscle of the heart; branched cells connected by intercalated disks; pumps blood.

Smooth Muscle

Non-striated, spindle-shaped muscle; involuntary; lines hollow organs and regulates lumen size.

Multipolar Neuron

Neuron with many dendrites and one axon; common in brain and spinal cord; integrates signals or information.

Pseudounipolar Neuron

Neuron with a cell body and a single process that divides into two branches; transmits sensory information to CNS.