Cytology Flashcards
Explain Cell Theory(3)
- Cells are the “building blocks” of all plants and animals
- Cells are produced by the division of pre-existing cells
Mitosis and Meiosis - Cells are the smallest units that perform all vital functions
what are the 2 types of cells
- Sex(germ cells/ gametes)- sperm(male)/Egg(female)
- Somatic Cells - cells of the body, everything that is not a sex cell
Describe extracellular Fluid(5)
- Usually a watery fluid (aka interstitial fluid)
- It is the matrix of connective tissue
- Little intercellular space in some tissues
- Provides a medium for nutrients, gasses, and waste
- May be blood or lymph within specific specific vessels
What are the 4 functions of the plasma membrane
- Physical Isolation
- Sensitivity
- Structural Support
- Regulation of exchange of materials
Define Physical Isolation(Plasma Membrane)
Physical isolation of cell contents form extracellular fluid, separates internal and external environments of the cell
Define Sensitivity and Structural Support(Plasma Membrane)
A. Sensitivity to changes in the extracellular fluid, responsiveness to changes
B. Structural Support of the cell
Define Regulation of exchange of materials
Regulation of exchange of materials between the cell and the extracellular fluid- selective permeability
What are the molecules of the plasma membrane( 4)
- Phospholipid molecules
- Proteins
- Cholesterol
- Glycolipids and Glycoproteins
Describe the 2 parts of the phospholipid molecule
- Phosphate head:
-hydrophilic, “water loving”-reacts with water, Polar=charged
-Align towards intra and extracellular fluids - Lipid Tail
-Hydrophobic, “water fearing” , non polar= non charged
-Align away from intra and extracellular fluid
Describe the two types of proteins
- Integral proteins- span membrane
- Form pores/channels - Peripheral Proteins- attach to inner or out structures
- Anchors cytoskeleton, forms gates, etc.
Describe Cholesterol
-Adds fluidity and structure to membrane
-Makes Bi-layer more impermeable to water-soluble substances
Describe glycolipids and glycoproteins
-“Sugar coating”, made of sugar
-Cell coat to possibly help cells bind (glycocalyx)
-Cell identification( like a fingerprint)
Define Active and Passive Transport
Passive process
1. No ATP (cellular energy) used by cell
2. Is concentration dependent
- High concentration-> low concentration
Active process
1. ATP (cellular energy) use is required
2. Not concentration dependent
List the 4 types of passive processes
- Diffusion
- Facilitated Diffusion
- Osmosis
- Filtration
List the 3 types of active processes
- Active transport
- Endocytosis
- Exocytosis
Define Diffusion
Substance moved from higher conc. To lower conc. By way of KINETIC ENERGY(thermal)
Define Facilitate Diffusion
Lipid- insoluble substances helped by membrane carrier protein (like swinging door) down a concentration gradient
Define Osmosis
Movement of water molecules across a membrane, high H2O concentration to low H2O concentration
Define Filtration
Dissolved Solutes moved across a membrane by external mechanical forces
Define Active Transport
Substances transported via membrane carrier protein usually AGAINST concentration gradient- ATP is used
Define Endocytosis
Cell membrane engulfs a molecule organism, forms a vesicle by pinching off and bringing the vesicle within
- independent of concentration gradient
Define Exocytosis
Substances transported via vesicle
- it fuses to membrane and opens to outside
- independent to concentration gradient
Name the membrane extensions(3)
- Microvilli
- Cilia
- Flagella
Describe Microvilli
- Primarily used in absorption
- Increases Surface Area
EX: on digestive track
Describe Cilia
- contains regularly arranged microtubules
- beats rhythmically to move particles along cell’s surface
Describe Flagella
- Similar to Cilia in design but longer
- Single Extension
EX: Sperm
Name the non-membranous Organelles
- Cytoskeleton
- Ribosomes
- Centrioles
Name the Membrane Bound Organelles (5)
- Nucleus
- Mitochondria
- Endoplasmic Reticulum
- Golgi Apparatus
- Lysosomes
Describe the nucleus
- Contains Genetic Material
- Directs Protein Synthesis
- Directs cellular structure functions
Describe the Mitochondria
- Uses oxygen for cellular respiration
- generates ATP(energy for the cell)
- Can divide so numbers vary
- All mitochondria of an individual come from their mother
Describe the Endoplasmic Reticulum
- Smooth Endoplasmic Reticulum
a. Synthesizes steroid and lipids - Rough Endoplasmic Reticulum
a. synthesizes proteins
Describe the Golgi Apparatus
- Stacks of flattened membranous sacs
- vesicle producing organelle
- Receives synthesized proteins and lipids from the endoplasmic reticulum
- Forms secretory vesicles
Describe Lysosomes
-“cell suicide packages”
1. Membrane enclosed sacs from the golgi apparatus
2. Contains enzymes capable of breaking down proteins, lipids, some carbs, and DNA and RNA
3. Digest phagocytized (eaten) foreign material
Describe Peroxisomes
- similar to lysosomes but come from preexisting Peroxisomes
- Used to Detoxify
