Bio 23 Sections 7-8 3.1, 3.2,3.3 Textbook Flashcards
What is the scientific study of cells?
Cytology
Who coined the word cellulae (little cells)?
Robert Hooke in 1663
About how many different kinds of cells are in the human body?
200 with various shapes and sizes and functions
What does the cell shape squamous look like?
A thin, flat, scaly shape, often with a bulge where the nucleus is. also looks like a sunny side-up egg.
What does the cell shape cuboidal look like?
Squarish- looking in the frontal section and about equal in height and width. liver cells are a good example.
What does the cell shape columnar look like?
Distinctly taller than wide, such as the inner lining cell of the stomach and intestines. They look like columns.
What does the cell shape polygonal look like?
They have irregularly angular shapes with four, five, or more sides
What does the cell shape stellate look like?
Having multiple pointed processes projecting from the body of the cell, giving it a starlike shape.
What does the cell shape spheroidal to oval look like?
Round to oval, as in the egg cells and white blood cells
What does the cell shape discoidal look like?
They are disk-shaped, like red blood cells.
What does the cell shape fibrous look like?
Long, slender, and threadlike, as in skeletal muscles and the axons.
The fluid between the nucleus and the surface membrane is called?
Cytoplasm
What is cytoplasm?
The contents of a cell between its plasma membrane and its nuclear envelope, consist of cytosol, organelles, inclusions, and the cytoskeleton.
What is the most important thing about a microscope?
Resolution
What is resolution?
The ability to reveal details.
If the enlargement fails to reveal any more useful details it is called?
Empty magnification
What is a scanning electron microscope (SEM)
A microscope that produces three-dimensional images at high magnification and resolution, but can only view surface features.
What is the plasma (cell) membrane made of?
Proteins and lipids.
What is cytosol?
It is a clear featureless, gelatinous colloid in which the organelles and other internal structures of a cell are embedded. also referred to as intracellular fluid (ICF)
What are the major components of the plasma membrane?
Cytoplasm
Cytoskeleton
Organelles (including nucleus)
Inclusions
Cytosol
All the body fluids not contained in the cells are collectively called what?
Extracellular fluid (ECF)
What is an example of extracellular fluid?
Blood plasma, lymph, and cerebrospinal fluid.
What does the plasma membrane do?
Defines boundaries for the cell, governs interactions with other cells, and controls the passage of materials into and out of the cells.
How does the plasma membrane appear under an electron microscope?
It appears as two parallel lines with a total thickness of 7.5 nm
The face that faces the cytoplasm is called?
The intercellular face of the membrane.
The face that faces the outward is called?
Extracellular face
What percent do lipids take up in the plasma membrane?
98%
What percent are phospholipids?
75%
What percent is cholesterol?
20%
What percent are glycolipids?
5%
Although proteins are only 2% of the molecules of the plasma what percent do they take up for the membrane weight?
50%
What is transmembrane protein?
An integral protein that extends through a plasma membrane and contacts both the extracellular and intracellular fluid.
Can the transmembrane proteins pass completely through the phospholipid bilayer? true or false
True
Are transmembrane proteins amphipathic molecules (meaning they have both hydrophobic and hydrophilic regions? True or false?
True