Biology Flashcards
Learn stuff (30 cards)
Specimen
Object being examined under microscope.
Light Microscope
Uses light to magnify a specimen.
Electron microscope
Uses electrons to magnify a specimen.
What does the arm/ handle of the microscope do?
Connects the eyepiece down to the base of the microscope.
What does the coarse focus of the microscope do?
Controls focus quickly to get the specimen into focus.
What does the fine focus of the microscope do?
Makes fine adjustments to obtain a sharper image.
What does the stage on the microscope do?
It is where you place the slide.
What does the objective lens do?
Magnifies the image of the specimen (4x, 10x, 40x).
What is the eyepiece/ ocular lens of the microscope?
Magnifies image produced by the objective lens (10x).
What does the condenser do?
Focuses light onto a specimen.
How do you find out the total magnification?
To find out the total magnification, you must times the eyepiece/ ocular lens magnification by the objective lens magnification. (For example, 10x eyepiece magnification and 40x objective lens magnification would equal 400x total magnification because you times the 10 by the 40).
What is meant by the field of view or FOV of the microscope?
The FOV is the width of the circle you see when you are looking through a microscope.
What is meant by the resolution when looking through a microscope?
The resolution is the focus/ clarity of an image.
What happens to the FOV if the magnification gets greater?
When the magnification gets greater, the FOV gets smaller.
How do you calculate/ estimate the average size of one cell?
First, calculate the total magnification. Then look at the FOV and figure out how many cells fit into the width of the FOV. Then divide the FOV width by the number of cells (For example, if the FOV was 2500 micrometres and 4 cells could fit into the FOV, then divide the 2500 by the 4 (2500/4). That would mean the average size of one cell in that scenario would be 625 micrometres.
How do you convert micrometres into millimetres?
1000 micrometres = 1 mm.
What are the characteristics of living things? (Mrs Grenc)
Movement
Respiration
Sensitivity
Growth
Reproduction
Excretion
Nutrition
Cells
What is the difference between living and non living things?
Non-living things do not need food or water. They don’t move or grow. They can’t reproduce or breathe.
What is a cell?
A cell is the basic unit of structure and function in all living things.
Explain the 3 principles of cell theory
All living things are made up of cells.
Cells are the smallest working unit of all living things.
All cells come from pre-existing cells through cell division (mitosis).
Name the 2 types of cells
Prokaryotic and Eukaryotic
What is the photosynthesis equation, and when does photosynthesis occur?
The equation is: carbon dioxide + water»_space; oxygen + glucose. Photosynthesis occurs in the presence of sunlight and chlorophyll in the chloroplast of plants.
State the mulitcellular levels of cellular organisation
Cells build tissues > tissues build organs > organs build organ systems > organ systems build organisms.
Give an example of a tissue, an organ, and an organ system.
Tissue: e.g. connective tissue, muscle tissue
Organ: e.g. heart, lungs
Organ system: e.g. digestive system, reproductive system
