Study Guide: The Cell Flashcards
What is homeostasis?
Each cell contributes to maintaining a stable internal environment, crucial for survival
What is the role of the cell membrane?
Regulates the movement of substances in and out of the cell
What is the composition of the cell membrane?
Lipid bilayer, embedded proteins, and cholesterol
What is the phospholipid bilayer?
Foundation of the membrane, composed of phospholipids with hydrophilic heads and hydrophobic tails
How does cholesterol function in the cell membrane?
Maintains membrane fluidity, allowing it to remain flexible and functional
Why is cell membrane fluidity important?
Allows adaptation to changes and maintains functions like endocytosis and exocytosis
What are integral proteins?
Proteins embedded in the membrane that facilitate the movement of substances
What are peripheral proteins?
Attached to the membrane surface, involved in signaling and maintaining cell shape
What does selective permeability mean?
The cell membrane allows only certain substances to pass through
What is diffusion?
Movement of molecules from high to low concentration without energy input
What is facilitated diffusion?
Use of carrier proteins to move large or polar molecules across the membrane
What is osmosis?
Diffusion of water across a semipermeable membrane
What is active transport?
Transport of molecules against their concentration gradient using energy
What is endocytosis?
The process by which cells internalize substances by engulfing them
What is phagocytosis?
Engulfment of large particles by cells
What is pinocytosis?
Ingestion of extracellular fluid and dissolved substances
What is receptor-mediated endocytosis?
Specific molecules are brought into the cell after binding to receptors
What is exocytosis?
The export of materials from the cell using vesicles that fuse with the cell membrane
What is cytoplasm?
Everything within the cell membrane, excluding the nucleus
What is cytosol?
Intracellular fluid within which organelles are suspended
What are organelles?
Specialized structures within cells that perform specific tasks
What is the nucleus?
The control center of the cell, containing genetic material (DNA)
What is the function of the nucleolus?
Produces ribosomal RNA (rRNA) and assembles ribosomes
What is chromatin?
A complex of DNA and protein found in the nucleus
What is the endomembrane system?
A series of compartments that modify, package, and transport lipids and proteins
What is the rough endoplasmic reticulum (RER)?
Studded with ribosomes and involved in protein synthesis
What is the smooth endoplasmic reticulum (SER)?
Lacks ribosomes, involved in lipid synthesis and detoxification
What is the Golgi apparatus’s role?
Modifies, sorts, and packages proteins and lipids for secretion
What do lysosomes contain?
Digestive enzymes that break down waste materials and cellular debris
What are mitochondria known for?
Generating ATP through cellular respiration
What are peroxisomes involved in?
Detoxifying harmful substances and lipid metabolism
What is the cytoskeleton?
A dynamic network of fibers providing structural support and facilitating cell movement
What are microfilaments composed of?
Actin
What is the function of intermediate filaments?
Provide tensile strength and maintain cell integrity
What are microtubules made of?
Tubulin
What role do centrioles play in cell division?
Organize microtubules and form the mitotic spindle
What initiates protein synthesis?
Transcription of DNA into mRNA in the nucleus
What is cellular respiration?
Conversion of glucose into ATP in mitochondria
What is the role of the SER in liver cells?
Detoxifying harmful substances
What is autophagy?
The process of recycling damaged organelles and proteins
What is apoptosis?
Controlled cell death necessary for development and disease prevention
