Week 2 Flashcards
The total magnifying power of a microscoe depends on the selection of what?
Objective lens
About how many cells are in the human body?
200
What are the characteristics of a squamous cell?
Thin, flat, and scaly
What are the characteristics of a cuboidal cell?
Squarish-looking
What are the characteristics of a columnar cell?
Looks like a column and is taller than wide.
What are the characteristics of a polygonal cell?
Irregular angular shapes, multiple sides.
What are the characteristics of a stellate cell?
It is star-like.
What are the characteristics of a spheroid to an ovoid cell?
Round to oval
What are the characteristics of a discoidal cell?
disc shaped
What are the characteristics of fusiform cells?
Thick in the middle, tapered toward the end.
What are the characteristics of a fibrous cell?
Thread-like
What is the size of most human cells?
10-15 um in diameter
What is the purpose of the plasma (cell) membrane?
To surround the cell and to define boundaries.
What is the plasma membrane composed of?
Proteins and lipids
What does the cytoplasm contain?
Organelles
Cytoskeleton
Inclusions (stored or foreign particles)
Cytosol (Interacewllular fluid. ICF)
What is Extracellular fluid (ECF)
Fluid outside of cells includes tissue (interstitial) fluid.
What is the cytoskeleton composed of?
Microfilaments, intermediate fibers and microtubles
What is the function of the cytoskeleton?
Determines the cell shape
Support structure
Organize cell contact
Directs movement of materials within a cell
Contributes to the movement of the cell as a whole
What is a cytoskeleton?
It is a network of protein filaments and cylinders
What are microfilaments composed of?
Actin proteins
What are intermediate filaments composed of?
Protein keratin.
What is the function of the intermediate filaments?
Give shape to cells and resists stress.
What are microtubules composed of?
Protofilaments are made of the protein tubulin.
What is the function of microtubules?
Maintain cell shape, holds organelles, and acts as a railroad track for walking motor proteins. They make axonemes of cilia and flagella and form the mitotic spindles.
What are organelles?
They are the internal structures of a cell and carry out specialized metabolic tasks.
What does a membranous organelles contain?
Nucleus
Mitochondria
Lysosomes
Peroxisomes
Endoplasmic reticulum
Golgi complex
What does a non-membranous organelle contain?
Ribosomes
centrosomes
centrioles
basal bodies