Cell Structures and Functions Vocabulary

Flashcards for vocabulary review of cell structures and functions lecture notes.

Vacuoles

Act as a storage for nutrients and waste materials, protecting the cell from toxicity and maintaining homeostasis by balancing pH.

Vesicles

Structures inside the cell formed naturally (exocytosis, endocytosis) or artificially (liposomes) for transport; types include vacuoles, secretory, and transport vesicles.

Lipid Bilayer

The outer enclosure of a vesicle, similar to the plasma membrane, with one hydrophobic end and one hydrophilic end.

Vesicle Functions

Storage and transport of materials in and out of the cell, exchange of molecules between cells, metabolism, enzyme storage, food storage, and controlling cell buoyancy.

Plastids

Usually oval or spherical organelles with an outer and inner membrane; the inner membrane encloses a matrix called stroma that contains grana.

Grana

Small structures within the stroma of plastids, composed of sac-like thylakoids piled one on the other and connected by stroma lamellae.

Plastid Functions

Involved in metabolic activities including photosynthesis and the storage of food, primarily starch; contains DNA and RNA for protein synthesis.

Ribosomes

Ribonucleoproteins containing RNA and proteins, existing freely in prokaryotes or attached to the endoplasmic reticulum in eukaryotes; site of biological protein synthesis.

Storage Granules

Membrane-bound organelles that store cells' energy reserve and other metabolites, surrounded by a lipid bilayer and composed mostly of phosphorus and oxygen.

Vacuoles

Membrane-bound structures varying in size, surrounded by a tonoplast, containing inorganic and organic materials.

Tonoplast

The membrane surrounding a vacuole, enclosing fluid containing inorganic and organic materials.

Mitochondria

Double membrane-bound cell organelles responsible for energy synthesis (ATP) and other functions like balancing Ca+ ions and detoxifying ammonia.

Nucleus

Double-membrane bound organelle that carries the cell's genetic information (DNA or RNA) and controls cellular activities; the 'brain' of the cell.

Peroxisomes

Oxidative membrane-bound organelles involved in the production and elimination of hydrogen peroxide, oxidation of fatty acids, and synthesis of lipids.

Plasmodesmata

Tiny passages or channels connecting adjacent cells that allow material transfer and communication between cells.

Nuclear Envelope

Similar to the cell membrane in structure, with pores that allow the movement of proteins and RNA in and out of the nucleus.

Chromatin

In the nucleus, contains RNA or DNA along with nuclear proteins as genetic material.

Nucleolus

Membrane-less organelle within the nucleus responsible for the synthesis of rRNA and the assembly of ribosomes.

Golgi Apparatus

Directs proteins and lipids to their destination; involved in exocytosis and the synthesis of cell organelles.

Intermediate Filaments

Contribute to the structural integrity of a cell and hold tissues of various organs.

Lysozymes

Membrane-bound organelles containing hydrolytic enzymes for the degradation of macromolecules, responsible for intracellular digestion and autolysis.

Microfilaments

Part of the cytoskeleton made of actin protein, providing strength and movement to the cell.

Microtubules

Part of the cytoskeleton made of tubulin protein, providing shape and movement to the cell, and facilitating organelle movement.

Microvilli

Tiny finger-like structures on cells that increase surface area, enhancing absorption and secretion.

Cytoplasm

Everything present inside the cell except the nucleus, containing cytosol, organelles, and cytoplasmic inclusions; site of cellular and enzymatic reactions.

Cytoskeleton

Fibrous structures in the cytosol that give shape to the cell and support cellular transport, made up of microtubules, microfilaments, and intermediate filaments.

Cell Membrane

Composed of a phospholipid bilayer and proteins, providing mechanical support, regulating material exchange, generating signals, and allowing cell interaction.

Cell Wall

Non-living layer outside the cell membrane that provides structure, protection, and filtering; made of cellulose in plants and chitin in fungi.

Endoplasmic Reticulum (ER)

Interconnection of tubules connected to the nuclear membrane; Rough ER (RER) involved in protein synthesis, Smooth ER (SER) involved in lipid synthesis.

Centrioles

Tubular structures in eukaryotic cells made of tubulin, forming spindle fibers during cell division.

Cilia and Flagella

Hair-like projections made of microtubules, responsible for movement of organisms and particles.

Endosomes

Membrane-bound compartments originating from the Golgi network, involved in sorting and delivering internalized materials.

Chloroplast

Type of plastid in plants and algae involved in photosynthesis, containing chlorophyll to trap sunlight for glucose production.

Cell Organelles

Specialized entities inside a cell performing specific functions; can be membrane-bound or without a membrane.