Skip to main content
뒤로

Anatomy & Physiology: Cytology and Cell Function

컨트롤 버튼이 '내비게이션' 모드로 변경되었습니다.
1/28

이 집합의 용어 (28)

  • What is the cell theory?
    Cell theory states that a cell is the structural and functional unit of life, all living cells arise from pre-existing cells, and all organisms are made of one or more cells.
  • What are the three basic parts of a generalized human cell?
    The three basic parts are: 1) Plasma membrane (flexible outer boundary), 2) Cytoplasm (intracellular fluid with organelles), and 3) Nucleus (DNA-containing control center).
  • Describe the structure of the plasma membrane.
    The plasma membrane is a fluid mosaic model consisting of a phospholipid bilayer with polar heads facing water and nonpolar tails inside, with floating integral and peripheral proteins.
  • What are the functions of membrane proteins?
    Membrane proteins allow cell communication, act as transport proteins, enzymes, receptors, and provide cell identity markers.
  • What are the differences between integral and peripheral proteins?
    Integral proteins span the membrane with hydrophobic and hydrophilic regions; peripheral proteins are loosely attached and involved in support, enzymes, motor functions, and cell recognition.
  • Name and describe the three types of cell junctions.
    Tight junctions prevent fluid passage; desmosomes provide mechanical strength; gap junctions allow small molecules and electrical signals to pass between cells.
  • What is passive transport and its types?
    Passive transport requires no energy and moves substances down their concentration gradient. Types include simple diffusion, facilitated diffusion, osmosis, and filtration.
  • Explain simple diffusion.
    Simple diffusion is the movement of hydrophobic substances like oxygen and carbon dioxide directly through the phospholipid bilayer down their concentration gradient.
  • What is facilitated diffusion and its two mechanisms?
    Facilitated diffusion transports hydrophilic molecules via carrier-mediated proteins that change shape and channel-mediated proteins that form aqueous pores.
  • Define osmosis.
    Osmosis is the movement of water across a selectively permeable membrane from areas of low solute concentration to high solute concentration.
  • What is tonicity and its types?
    Tonicity is a solution's ability to change cell shape by altering water volume: isotonic (no change), hypertonic (cell shrinks), and hypotonic (cell swells).
  • What distinguishes active transport from passive transport?
    Active transport moves solutes against their concentration gradient using ATP, while passive transport moves solutes down the gradient without energy.
  • Describe primary active transport.
    Primary active transport uses ATP to change protein shape and pump solutes like ions across the membrane, e.g., Na+-K+ pump.
  • What is secondary active transport?
    Secondary active transport uses energy stored in ion gradients created by primary transport to move other solutes indirectly.
  • Explain vesicular transport.
    Vesicular transport moves large substances via vesicles: endocytosis brings substances in, exocytosis expels substances out of the cell.
  • What is resting membrane potential (RMP)?
    RMP is the electrical potential energy from charge separation across the plasma membrane, typically around -70 to -90 mV inside the cell.
  • Which ion is key in establishing RMP and why?
    Potassium (K+) is key because it leaks out of the cell, leaving behind negatively charged proteins, making the inside more negative.
  • Name the membranous organelles in a cell.
    Membranous organelles include the nucleus, mitochondria, endoplasmic reticulum, Golgi apparatus, peroxisomes, and lysosomes.
  • What is the function of the mitochondria?
    Mitochondria produce most of the cell's ATP through aerobic cellular respiration and contain their own DNA and ribosomes.
  • Describe the rough and smooth endoplasmic reticulum (ER).
    Rough ER has ribosomes and synthesizes proteins; smooth ER lacks ribosomes and functions in lipid synthesis and detoxification.
  • What is the role of the Golgi apparatus?
    The Golgi apparatus modifies, concentrates, and packages proteins and lipids received from the rough ER for transport.
  • What are ribosomes and their types?
    Ribosomes are protein synthesis sites made of rRNA and protein; they can be free in cytoplasm or membrane-bound on rough ER.
  • What are cilia, flagella, and microvilli?
    Cilia are hair-like extensions that move substances across cell surfaces; flagella propel the whole cell; microvilli increase surface area for absorption.
  • What are the stages of mitosis?
    Mitosis stages are prophase, metaphase, anaphase, and telophase, ensuring DNA is equally divided into daughter cells.
  • What is the central dogma of molecular biology in protein synthesis?
    DNA is transcribed into RNA, which is then translated into proteins, following the sequence: DNA → RNA → Protein.
  • What is transcription?
    Transcription is the process of copying DNA's base sequence into complementary mRNA in the nucleus.
  • What is translation?
    Translation is decoding mRNA into a polypeptide chain at the ribosome using tRNA and the genetic code.
  • What is the role of tRNA in translation?
    tRNA carries specific amino acids and uses its anticodon to pair with mRNA codons, adding amino acids to the growing protein.