Chapter 2: Basic Components Of Living Systems Flashcards
The resolution of a microscope…
Determines the amount of detail that can be seen - the higher the resolution, the more details are visible.
Calculation for magnification
Magnification = image size/actual size
I=AM
Image size = actual size x magnification
In a transmission electron microscope…
A beam of electrons is transmitted through specimen and focused to produce and image.
In a scanning electron microscope…
A beam of electrons is sent across the surface of a specimen and the reflected electrons are collected.
Does TEM or SEM have the best resolution?
TEM
3 facts about using a light microscope…
- inexpensive
- small and portable
- simple sample preparation
- vacuum not required
- specimens can be living or dead
- up to 2000x magnification
- resolving power is 200nm
3 facts about using an electron microscope…
- expensive to buy and operate
- large and require installation
- complex sample preparation
- vacuum is required
- over 500 000x magnification
- specimens are dead
Prokaryotic cells are…
Single called organisms with a simple structure.
Eukaryotic cells are…
Much more complex with their internal structure and make up multicellular organisms.
Metabolism is…
The reactions that take place in the body, including synthesis and breaking down molecules.
The nucleus contains…
Coded genetic information in the form of DNA.
Mitochondria are…
The site of cellular respiration where energy is stored in the form of adenosine triphosphate.
Lysosomes contain…
Hydrolytic (digestive) enzymes to break down waste material and old organelles.
The cytoskeleton is made up of…
Microfilaments: contractile fibres formed from the protein actin. They are responsible for cell movement.
Microtubules: globular proteins. They determine the shape of the cell and act as tracks for movement.
Intermediate fibres: give mechanical strength to cells and maintain integrity.
Centrioles are involved in…
The assembly and organisation of spindle fibres during cell division.
