The Cell (Part 2) Note Outline PDF

BIOL 101 The Cell (Part 2) 1 https://www.nikonsmallworld.com/news/stunning-microscopic-view-of-human-skin-cells-wins-2017-nikon-small-world-competition  Eukaryot...

BIOL 101 The Cell (Part 2) 1 https://www.nikonsmallworld.com/news/stunning-microscopic-view-of-human-skin-cells-wins-2017-nikon-small-world-competition  Eukaryotic Cells: Structure and Function Although we begin life as only one cell, that cell differentiates into many _______________ specialized cells These specialized cells have structures that reflect their particular functions Plasma membrane Microfilament Microtubule Centrioles Regulates movement of Plays a role in muscle Maintains cell shape and forms May function materials into and out of cell contraction and cell division tracks on which vesicles move in cell division Cytoplasm The material surrounding the nucleus Lysosome Digests substances brought into cell and destroys old parts of cells Mitochondrion Provides cell with energy through the breakdown of glucose during cellular respiration Nucleus Contains DNA and controls cellular activity Nucleolus Produces components of ribosomes (RNA and proteins) Ribosome Site where protein synthesis begins Rough endoplasmic reticulum Studded with ribosomes and produces membrane Smooth endoplasmic reticulum Detoxifies drugs and produces membrane Golgi complex Sorts, modifies, and packages proteins 10–100 µm 3  Plasma Membrane ____________________ The outer boundary of the cell Controls the movement of substances in and out of the cell The phospholipid bilayer separates the extracellular fluid from the material contained in the cytoplasm inside the cell ________, Proteins _________, and ________ cholesterol carbohydrates are also part of the membrane and give it the qualities of a fluid mosaic  Plasma Membrane Carbohydrate Figure 3.6 Glycoprotein Plasma membrane Embedded Cholesterol Glycolipid Outer surface of protein plasma membrane Extracellular fluid Plasma membrane Inner surface of plasma membrane Phospholipid bilayer Surface Filaments of Cytoplasm protein cytoskeleton 5 Figure 3.6  Functions of the Plasma Membrane Maintains structural integrity of the cell ________________as Selectively permeable it regulates movement of substances into and out of the cell ___________ Glycoproteins provide recognition between cells ________ provide communication between cells Receptors ____________________stick Cell adhesion molecules cells together to form tissues and organs  Types of Transport Across Plasma Membrane There are two types of movement across the plasma membrane: _______________ Passive transport Movement across the membrane that doesn’t require energy Simple diffusion, facilitated diffusion, osmosis _______________ Active transport Movement across the membrane that requires energy  Mechanisms of Transport Across Membranes 1. ___________ Diffusion (simple and facilitated) (small and non-polar) 2. ___________ Osmosis (water) 3. ___________ Active transport (needs energy, involves other proteins that is in the membrane) 4. ___________ Endocytosis (absorb in) 5. ___________ Exocytosis (getting rid of) 8  Simple Diffusion Movement of a substance following a concentration gradient, from high ____ concentration to ____ low concentration End result is an ____ equal distribution of the substance in the two areas _________ the concentration gradient Eliminates  A lipid-soluble substance moves through the lipid bilayer from high to low concentration. Extracellular fluid High concentration Plasma membrane Low concentration Cytoplasm 10 Figure 3.7  Facilitated Diffusion Movement of a substance from a region of ______concentration higher to a region of ______ lower concentration with the aid of a membrane protein To cross a cell membrane, water-soluble substances need to be assisted or “facilitated” by __________ carrier proteins  Glucose moves through the lipid bilayer from high to low concentration with aid from a carrier protein. Extracellular fluid High Glucose concentration Carrier protein Plasma membrane Low concentration Cytoplasm 12 Figure 3.8  Osmosis Movement of_______ water across a __________membrane permeable from a region of higher water concentration to a region of lower water concentration The water molecules move to dilute the solution  The bag gains and loses the same amount of water and maintains its shape. 98% water, The bag gains The bag loses more water than 2% sugar it loses and swells. more water than it gains and shrinks. Osmosis (a) Hypertonic (b) Isotonic (c) Hypotonic solution solution solution (90% water, (98% water, (100% water, 10% sugar) 2% sugar) distilled) 14 Figure 3.9  Active transport Movement from a region of lower _____ to _____ higher concentration with the aid of a carrier protein and energy, typically ATP ____  Endocytosis A region of the plasma membrane engulfs the substance to be ingested and then pinches off from the rest of the membrane, enclosing the substance in a vesicle, which travels through the cytoplasm Applies to __________, large molecules _________, single-celled organisms and droplets of fluid containing dissolved substances Two types of endocytosis: _________________________________________ Phagocytosis (cell eating): large partivles or bacteria _________________________________________ Pinocytosis (cell drinking): droplets of fluid  Endocytosis Figure 3.11  Exocytosis Large molecules are _______________________________, enclosed in membrane-bound vesicles which travel to plasma membranes, where they are released to the outside Endocytosis and Exocytosis  Review of Mechanisms of Transport across the Plasma Membrane Mechanism Description Simple diffusion Random movement from region of higher concentration to region of lower concentration Facilitated diffusion Movement from region of higher concentration to region of lower concentration with the aid of a carrier or channel protein Osmosis Movement of water from region of higher water concentration (lower solute concentration) to region of lower water concentration (higher solute concentration) Active transport Movement, often from region of lower concentration to region of higher concentration, with the aid of a carrier protein and energy, usually from ATP Endocytosis Process by which materials are engulfed by the plasma membrane and drawn into cell in a vesicle Exocytosis Process by which a membrane-bound vesicle from inside the cell fuses with the plasma membrane and spills contents outside the cell  Organelles Inside eukaryotic cells are membrane-bound organelles, which have different functions Organelles include: ____________ Nucleus ____________ endoplasmic reticulum ____________ Golgi apparatus ____________ Lysosomes ____________ Mitochondrion Non-membranous organelles also perform specific cellular functions 22  Nucleus Contains almost all of the genetic information of the cell, _____ DNA Nucleus Surrounded by _____________, nuclear envelope a double membrane that allows communication through ___________ nuclear pores The genetic information is organized into _______________ chromosomes Chromosomes are threadlike structures made of DNA, and associated proteins called _______ histones Humans have 46 chromosomes (23 pairs) in the loose form (chromatin) or condensed, which are then visible in the light microscope during cell division 23  Nucleolus A specialized region within the nucleus Involved in the production of ribosomal RNA (rRNA) Nucleolus 24  Endoplasmic Endoplasmic Reticulum Reticulum 25  Endoplasmic Reticulum An extensive network of channels connected to the plasma membrane, the nuclear envelope, and certain organelles Two types of endoplasmic reticulum: § Rough endoplasmic reticulum (RER) ___________________________________________________ an extensive network channels connected to the plasma membrane, the nuclear envelope, and certain organelles § Smooth endoplasmic reticulum (SER) ________________ Contains no ribosomes __________________________________________________ Involved in the production of phospholipids and detoxifiction  Ribosomes Take an mRNA copy of a gene and turn it into protein Ribosomes Found on ER or freely floating in cytoplasm 27  Golgi complex A series of ___________, interconnected flattened membranous sacs Proteins are _________ packaged in vesicles and transferred to the Golgi complex for ________ processing and ________ packaging Golgi Complex 28  Lysosome Lysosomes Contain about 40 digestive ____________that enzymes break down macromolecules, old organelles, and invaders - Releases toxic material out of cell Figure 3.1 29  Mitochondria Sites of ____________, cellular respiration providing cell with energy through the breakdown of glucose to produce ATP ________-membrane organelle § Double § Contain inner foldings, called _______, cristae that provide increased membrane surface for cellular respiration § Singular: ______________ Mitochiondria Mitochondria 30  Mitochondria – double membrane bound structure – provides energy in the form of ATP Figure 3.19 31 Cytoskeleton Microfilaments Centrioles Microtubules 32  Cytoskeleton Network that provides shape and support for the cell Composed of thick ____________, microtubules ________________, intermediate filaments and thin ______________ microfilaments Centriole: ___________________________________ A mictrotubule-organizing centre located near the nucleus Microtubules and microfilaments disassemble and reassemble, while intermediate filaments tend to be more permanent  The plasma membrane is composed of _____. a) proteins b) phospholipids c) cholesterol d) all of the above © 2017 Pearson Education, Inc.  When a membrane is said to be selectively permeable, this means that _____. a) half of the membrane is permeable, and the other half is not b) only water can pass through it c) the membrane regulates movement of substances into and out of the cell d) the membrane is permeable only part of the time © 2017 Pearson Education, Inc.  Which of these is a function of the plasma membrane? a) Maintains structural integrity of the cell b) Is selectively permeable to regulate movement of substances into and out of the cell c) Contains glycoproteins to provide recognition between cells d) All of these are functions © 2017 Pearson Education, Inc.  Cells placed in a hypotonic solution _____. a) shrink b) swell c) do not change volume d) there is no way to determine this © 2017 Pearson Education, Inc.  Which is a form of diffusion where the molecules pass through a protein channel instead of between the phospholipids? a) Cellular respiration b) Diffusion c) Facilitated diffusion d) Mitochondria © 2017 Pearson Education, Inc.  Which process brings particles into the cell by the formation of a vesicle in the plasma membrane? a) Endocytosis b) Exocytosis c) Homeostasis d) Osmosis © 2017 Pearson Education, Inc.  Which organelle contains almost all of the genetic material of the cell? a) Nucleus b) Nucleolus c) Rough endoplasmic reticulum d) Cytoplasm © 2017 Pearson Education, Inc.  Which organelle is membranous, modifies proteins, and uses vesicles to ship them to other organelles or out of the cell? a) Nucleus b) Mitochondria c) Golgi complex d) Lysosome © 2017 Pearson Education, Inc.  Which organelle performs protein synthesis? a) Chromosomes b) Nucleus c) Lysosomes d) Ribosomes © 2017 Pearson Education, Inc.  Which organelle contains enzymes that break down macromolecules, old organelles, and invaders? a) Mitochondrion b) Nucleus c) Endoplasmic reticulum d) Lysosomes © 2017 Pearson Education, Inc.