Chapter 2 Flashcards
Cell
the smallest structural and functional unit of an organism, typically microscopic and consisting of cytoplasm and a nucleus enclosed in a membrane.
Nucleic Acids
a complex organic substance present in living cells, especially DNA or RNA, whose molecules consist of many nucleotides linked in a long chain.
RNA
RNA transcribed inside the nucleus is exported to the cytoplasm through nuclear pores. They act as a gateway allowing only specific materials in and out of the nuclear envelope
Microscopy
A technique used for producing visible images of objects, biological or otherwise, that are too small to be seen by the human eye.
Illumination
the act of illuminating or the state of being illuminated
Magnification
how much bigger you can make an object appear dependent upon the lens system
Resolution
measure of the clarity of the image or ability to differentiate between two dots dependent upon the wavelength of light used
==> Blue light has a shorter wavelength than red (400 vs 600 nm) so it will provide better resolution
==> x-rays have an even shorter wavelength and can provide even greater resolution
View
inside or outside of the cell, type of light
Plasma Membrane
a phospholipid bilayer with proteins that separates the cell from the surrounding environment and functions as a selective barrier for the import and export of materials
Bilayer
A double layer of phospholipids in which the tails face inwards and are hydrophobic and the phosphate groups face outwards and are hydrophilic. This allows for the membrane to be selectively permeable.
Hydrophobic
‘repels water’
Hydrophilic
‘likes water’
Gene
A unit containing the code for a protein molecules or one of its parts, or functioning RNA molecules such as tRNA and rRNA
Cytoplasm
All parts of the cell that surround the central nuclear or nucleoid region
Organelle
The nucleus and other specialized internal structures and compartments of eukaryotic cells
Cytoskeleton
The interconnected system of protein fibres and tubes that extends throughout the cytoplasm of a eukaryotic cell
Prokaryote
Organism in which DNA is suspended in the cell interior without separation from other cellular components by a discrete membrane
Eukaryote
Organisms in which DNA is enclosed in a nucleus