13 Mar Flashcards
(26 cards)
How many parts of the microscope are there?
14
What are the fourteen parts of the microscope?
Body tube Rotating nose piece Three objective lenses Stage clips Diaphragm and iris Light source Ocular lens Arm Stage Coarse focus Fine focus Base
What is the body tube?
The tube that connects the eye piece to the objective lenses
What does the rotating nose piece do?
Holds the objective lenses and allows the observer to choose different powered objectives
What do the objective lenses do?
Magnify the specimen even more
What are the three types of objective lenses?
Low medium and high power objectives
What are the general magnifications of the objective lenses?
Low- 2-10 x
Medium- 20x
High- 40x
What is the general magnification of the eyepiece (ocular) lens?
10x
What do stage clips do?
Hold the specimen in place
What do the diaphragm and iris do?
Control the light that lights up the specimen from beneath
What is the light source?
The thing that generates the light that lights up the specimen from beneath
What does the arm of the microscope do?
Holds the lenses above the stage
What does the ocular (eyepiece) lens do?
Directs the light to the eye
Magnifies the image ten times
What does the stage do?
Holds the specimen
What does the coarse focus do?
It is the general focus of the microscope
What does the fine focus do?
It focuses the details of the image
What does the base do?
It is the foundation of the microscope
What is the process of specialisation?
It is when cells or tissues change so that they can perform their specific functions i.e. stem cell changes to muscle cell
What is the definition of prokaryotic cells?
Cells which do not have membrane-bound organelles e.g. no nucleus
What is the definition of eukaryotic cells?
Cells that do have membrane-bound organelles e.g. nucleus
What is the definition of cyclosis?
The movement of the cytoplasm within the cell
This movement allows materials within the cytoplasm to reach all of the parts of a cell
What is the definition of the fluid mosaic model?
A model used to demonstrate the structure of a cell membrane, which consists of carbohydrates, lipids and proteins
What is the definition of an organelle?
The smaller structures within a cell that each perform a specific function
What is the definition of pectin?
A water soluble carbohydrate that gives plant cell walls extra structure and strength
