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Exam 2
The Cell, Metabolism, Tissues
21
Anatomy
Undergraduate 2
03/05/2013

Additional Anatomy Flashcards

 


 

Cards

Term
THE CELL
Definition

  basic unit of life, yet many different shapes and functions

Term
  Chemical composition of a Cell
Definition

80% water

                                     19% protein, lipid and carbohydrate

                           1% nucleic acid and minerals

Term
CELL MEMBRANE OR PLASMA MEMBRANE 
Definition

     FUNCTION:


Cell membrane is the major regulatory component of the cell.

                    Maintains homeostasis

           a) boundary – separates intracellular and extracellular

           b) cell recognition - receptors,antigens.

           c)  regulates transport – selectively permeable

           d) maintains voltage – membrane potentials

Term
CELL MEMBRANE OR PLASMA MEMBRANE STRUCTURE
Definition

7%Protein

            90% Phospholipids and cholesterol

            3% Carbohydrate

 

a) Phospholipids form a bilayer, with hydrophobic (water fearing) ends to inside and hydrophillic (water loving) ends to outside.

Cholesterol - other lipid component - stabilizes and lends flexibility.


b)              Proteins  Integral and peripheral 

                    1.  pumps and channels:  transport

                    2.  structural - integrity of membrane

                    3.  receptors - identification

                    4.  enzymes - chemical reactions

                    5.  junctions – CAM’s

c)  Carbohydrates are attached to proteins and lipids - forming glycoproteins and     glycolipids – glycocalyx.  Part of receptors for cell recognition.

Microvilli - folds of cell membrane - increases surface area

Term
PASSIVE TRANSPORT 
Definition

a)    Diffusion - random movement of molecules from a high to low concentration until equilibrium.  (with the gradient)

 

                    Brownian motion:

 

                      examples:  ions, O2, CO2, lipid soluble molecule 


affected by size of molecules, medium & temperature and gradient

                      

                    Facilitated diffusion:  use of protein carriers in membrane 

               b)  Osmosis - movement of water through a selectively permeable                           membrane from  a high to low concentration until equilibrium. solutes lower water concentration. 

 

                    responsible for osmotic pressure.

 

                          solutes ­ ↑ osmotic pressure ­↑

                   

                          solutes ¯  osmotic pressure ¯

 

Term
 Hypertonic
Definition
water concentration is higher inside the cell - water leaves cell
Term
Hypotonic
Definition
water concentration is higher outside the cell - water enters cell
Term
Isotonic
Definition
water concentration equal inside and outside cell - equal                           amounts of water enter & leave cell
Term
Filtration
Definition
external force supplied
Term
ACTIVE TRANSPORT
Definition

uses energy (40% of energy made by cell). Uses proteins in membrane as carriers. Transport against the gradient-low to high concentration.

                             

                    Sodium / Potassium pump (antiport)

                       examples:  glucose, amino acid

 

          Can utilize as cotransport mechanisms (symport)

Term
ENDOCYTOSIS
Definition
active movement of membrane
Term
Phagocytosis
Definition

engulfing of particles by cell

 

Term
Pinocytosis
Definition

formation of endosome (vesicle)

                     - Important for hormones & proteins

                     -  Method of immunity for fetus


receptor-mediated pinocytosis

Term
EXOCYTOSIS
Definition
secretion
Term
CYTOPLASM
Definition

1. Cytosol- liquid matrix of cell - gel

            70 -90% water, rest protein, lipid & glycogen 

 

2.     Cytoskeleton-Shape, transport, movement

 

             

Term

 

Microtubules   .02   mm

 

 

Definition

Structure long thin tubes made of protein - no membrane.

            found throughout cytoplasm as scaffolding.Assembles on one end & disassembles on other end.  Made from MTOC. 

 

 

Term
Microtubules
Definition

Function

            Cell support and intracellular movement (cytokinesis).

            formation of spindle.

           Forms centrioles, source of basal body for ciliaflagella

 

Term
Microfilaments  .08    mm
Definition

Structure

           thin filaments of protein called actin (similar to muscle) - no membrane, part of scaffolding, especially in outer part of cytoplasm.

Term
Microfilaments
Definition

Function

           cell movement - especially in muscle cells.

            cell shape - cytoplasmic streaming.

           support for microvilli.

           contractile ring in cell division during cytokinesis.

Term
Intermediate filaments 10nm
Definition

Structure intermediate size - examples are keratin, neuro-filaments, etc.

 Function mechanical strength, varying other functions.

 

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