Module 3: Cytology Flashcards
Cell Shape: Squamous
Thin, flat scaly. Bulge where nucleus is, like a fried egg; found in esophagus & epidermis
Cell Shape: Cuboidal
Squarish, and sometime ball-shaped; equal length & height; found in liver cells
Cytology
study of cells; cells are 1st level to display life
Cytoplasm
fluid between nucleus and surface membrane; made up of cytosol & organelles.
Cytosol: aka; composed of; location; examples
aka intracellular fluid;
primarily water;
surrounds cytoskeleton, organelles, inclusions.
ex/ blood plasma, lymph, cerebrospinal fluid
Cytoskeleton
supportive framework of protein filaments and tubules, providing internal support
Organelles
structures that perform various metabolic tasks and cellular funtions
Plasma Membrane: describe, composition and function
aka cell membrane; made up of proteins and lipids;
surrounds the cell providing shape, protection,
communicates with cells, and is semipermeable
What can freely pass through plasma membrane?
hydrophobic and small, uncharged polar molecules
such as water, oxygen, CO2, vitamins and steroids’
What cannot freely pass through plasma membrane
hydrophilic, large charged molecules ie. proteins, ions, glucose
these molecules need help of channels or carrier proteins to get into cell.
Phospholipid Bilayer: describe properties
Semi-permeable & Amphipathic - with a hydrophilic phosphate heads facing cellular fluid, and hydrophobic fatty acid tails facing the center avoiding water
Membrane Lipids include: P.C.G
phospholipid bilayer, cholesterol, glycolipids
Cholesterol
found between phospholipids providing some rigidity, they stiffen the membrane making it less fluid
Glycolipids:
Structure
Location
Made of phospholipids & carbohydrate
found on extracellular surface of membrane
______ ______ enable ions and large polar particles to pass into _______ _____ or all the way through. They drift freely in phospholipid film and are exposed where?
Integral Proteins
phospholipid bilayer
exposed on inside & outside of cell
Peripheral Proteins
exposed to just the ECF & ICF
Transmembrane Proteins
aka integral proteins
within the membrane exposed on inside & outside of cell
Receptors: fxn
communication for neurotransmitters and hormones
Second Messenger System
binds to a surface receptor
relays signals from outside to inside of cell
Enzymes
breakdown chemical messengers and nutrients
Channel Protein
Transmembrane; passages that allow water and hydrophilic solutes to move through membrane;
two type - Leak channels & Gated Channels
Leak Channels
always open & allow materials to pass through
Gated Channels open & close responding to 3 types of stimuli/gates
Ligand gated, voltage gated and mechanically gated channels
Ligand Gated Channels
respond to chemical messengers
Voltage Gated channels
respond to changes in electrical potential
Mechanically gated channels
respond to changes to physical stress on cell, like stretch and pressure
Carriers
Transmembrane; Shuttle large molecules, like glucose and electrolytes through membrane. Some carriers called pumps consume ATP in the process
Cell-identity Markers
Glycoproteins (sugars and Amino Acids) that identifies cells as “self”, which cells belong and which are invaders.
Glycocalyx
fuzzy coating of carbohydrates.
fxn in protection, immunity to infections, cell adhesion
Cell-adhesion molecules
(CAMs) physically connect adjacent cells through membrane proteins
Surface extensions: 3 types & describe role
includes microvilli, Cilia, and Flagella; aid in absorption, movement, sensory processing
Microvilli
extension of plasma membrane that increase surface area;
fxn in absorption of nutrients
role in hearing and taste
Microvilli Example
epithelial cells of intestine and kidneys
Cilia
hair-like processes; role in smell and vision;
some don’t move & have sensory fxns (inner ear sense of balance -non-motile)
others move and help propel fluid (pump mucus- motile)
Flagella
whip-like tail of sperm propelling them
_____ _______ allows for some nutrients and wastes through but prevents _____ & ______ from entering or leaving cells
Selective Permeability
proteins and phosphates
Passive Transport: describe properties and methods (FFSO)
requires no ATP; movement occurs by filtration, simple diffusion, Facilitated Diffusion and osmosis
Active Transport
Requires ATP; moves substances through a protein from low concentration to high concentration.
Carrier-mediated Transport
use transmembrane protein to transport substances through membrane; exhibits specificity for its ligands (ex/ glucose carrier cannot transport fructose)
Cell Shape: Columnar
Tall & Thin; found in lining of stomach and intestines
Phospholipids
Amphiphilic; do not attach to each other, but move independently next to each other; allows membrane to be fluid & flexible
Filtration
transport that uses hydrostatic pressure to move particles across membrane; ex/ coffee filters, blood capillaries
Simple Diffusion
movement of particles down a concentration gradient from areas of high to low.
Osmosis
diffusion of water; moves water down concertation gradient; ex/ diarrhea, hypertension, edema
Facilitated Diffusion
Passive; requires transport proteins; moves down concentration gradient through a membrane protein; No ATP required (ex/glucose cannot pass through un aided)
Vesicular Transport
used to move large molecules across membrane contained in vesicles; requires ATP
Endocytosis
moves substances into cells
Exocytosis
moves substances out of cells
Nucleus
Control center; holds DNA
Nuclear Envelope
Surrounds Nucleus in a bi-layer membrane
Nucleolus
Found within the Nucleus; produces ribosomes
Endoplasmic Reticulum (ER)
cells consisting of channels called cisternae; Two type are Smooth ER & Rough ER; synthesizes steroids’ and lipids
Rough Endoplasmic Recticulum
continuous with nuclear envelope;
contains ribosomes
fxn in protein synthesis
Smooth Endoplasmic Recticulum
continuous with Rough ER; no ribosomes; detoxifies the cytoplasm
Ribosomes
produced by nucleolus;
Found in Rough ER, Nucleolus, Cytosol & Mitochondria;
read genetic material & role in protein synthesis
Golgi Complex
made of flat sacs called cisternae; synthesizes & packages peptide, protein and carbs.
Golgi Vesicles
finished proteins from the Golgi complex are packaged in these vesicles and are transported within the cytoplasm
Lysosomes
specialized Golgi vesicles; contain digestive enzymes, travel around cell, break down organelles and particles
What type of organelle do WBCs use to breakdown bacteria inside the cell?
Lysosomes
What type of organelle do liver cells use to release stored glucose into the blood?
Lysosomes
Peroxisomes
similar to lysosomes
produced in smooth ER rather than Golgi complex;
detoxify cells by producing hydrogen peroxide;
Mitochonria
oval organelles composed of folds called Cristae; synthesizes ATP; referred to as “power house” of the cell
Centrioles
paired organelles that are arranged perpendicular to one another; contains numerous microtubules aiding in cell division
Microtubules
proteins responsible of moving and arranging components in cytosol to insure cell divides equally
Factors that effect rate of Simple Diffusion
Temp. Molecular weight Concentration gradient (greater the difference the faster it will diffuse) surface area permeability
When endothelial cells release insulin to tissues, sperm cells release enzymes for penetrating an egg; This is an example of what process?
Exocytosis
