Chapter 1_1 flashcards
(33 cards)
Cell: Basic Definition
The basic unit in which all structural, functional, and environmental alterations occur in disease processes[cite: 1]. Composed of a plasma membrane, cytoplasm, organelles, and a nucleus[cite: 1].
Plasma Membrane: General Function
Acts as a barrier to the cell’s external environment and protects internal organelles from injury[cite: 1]. It is semipermeable, selectively allowing substances in or out[cite: 1].
Glycoproteins: Function on Plasma Membrane
Surface markers, also called antigens, that identify cells as part of the individual’s own tissues[cite: 1]. Alterations can provoke immune responses (basis for allergies, autoimmune disorders, transplant rejection, transfusion reactions)[cite: 1].
Sodium-Potassium Pump (Na+/K+ Pump): General Role & Energy
Maintains cellular movement of Na+ outside and K+ inside the cell[cite: 1]. Requires energy (ATP) for active transport[cite: 1].
Active Transport vs. Passive Transport: General Difference
Active transport requires energy (e.g., ATP) to move substances across a membrane, often against a concentration gradient[cite: 1, 2]. Passive transport (like diffusion, osmosis) does not require energy and typically moves substances down a concentration gradient[cite: 1, 2].
Cytoplasm: Definition
A colloidal internal fluid environment that contains water, ions, proteins, carbohydrates, and lipids; it suspends the cellular organelles[cite: 1].
Organelles: Definition
Specialized intracellular structures that carry out specific activities to sustain life[cite: 1].
Nucleus: General Function
Contains the body’s genetic material, DNA, which ultimately regulates all cell structure and function[cite: 1].
Cilia: General Function in Respiratory Tract
Cellular projections containing microtubules that propel substances along the outside of cells[cite: 1]. In the respiratory tract, they propel mucus and inhaled debris out of the lung through a sweeping motion[cite: 1, 4].
Microfilaments (Actin Filaments): General Role
Solid, flexible fibers that help the cell change shape, as seen in amoeboid movements of macrophages and muscle contraction[cite: 1, 5].
Secretory Vesicles: General Function
Formed by the ER–Golgi apparatus system, they store substances (like hormones, neurotransmitters) that are secreted by cells before their release into the extracellular space[cite: 1, 6].
Endoplasmic Reticulum (ER): General Function
A network of tubules within the cell that act as a transport system[cite: 1].
Rough Endoplasmic Reticulum (Rough ER): Function
A tubular network with attached ribosomes that synthesize proteins destined for parts of the cell, enzymes, or export[cite: 1, 7].
Smooth Endoplasmic Reticulum (Smooth ER): Function
Location for lipid production (corticosteroids, oils, phospholipids) and detoxification[cite: 1, 7].
Lysosomes: General Function
Small, membrane-enclosed organelles with an acidic internal environment, containing digestive enzymes (lysozyme, proteases, lipases) to degrade ingested foreign substances and cellular debris[cite: 1, 8].
Mitochondria: General Energy-Producing Role
The cell’s energy producers; convert organic nutrients into cell energy in the form of ATP through aerobic metabolism[cite: 1, 11].
Ribosomes: General Function
Small, spherical organelles composed of rRNA; act as cellular “protein factories” where protein synthesis occurs under direction from mRNA[cite: 1].
Golgi Apparatus: General Function
Processes, packages, and secretes proteins received from the ER (e.g., converting prohormones to actual hormones)[cite: 1].
Microtubules: General Function
Hollow filaments composed of tubulin; involved in cell division (centrioles, mitotic spindle) and provide pathways for transporting secretory vesicles[cite: 1].
Aerobic Metabolism: Location & ATP Yield
Occurs at the mitochondria and requires oxygen[cite: 1]. Yields a net of 34 ATP[cite: 1].
Anaerobic Metabolism (Glycolysis): Location, ATP Yield & Byproducts
Occurs outside the mitochondria within the cytoplasm[cite: 1]. Yields a net of 2 ATP and pyruvic acid (which can convert to lactic acid in hypoxia)[cite: 1].
Deoxyribonucleic Acid (DNA): Role
The body’s genetic material, located in the nucleus, that regulates all cell structure and function[cite: 1].
Transcription: General Definition & Location
The process where one strand of DNA acts as a template for the synthesis of a complementary RNA molecule[cite: 1]. Occurs in the nucleus[cite: 1].
Translation: General Definition & Location
The process where ribosomes interpret the message from mRNA to manufacture specific proteins, using tRNA to gather and join amino acids[cite: 1]. Occurs at the ribosomes[cite: 1].
