UNIT 1 - cells and organelles Flashcards
who was the first person to use the term “cell”?
robert hooke
what are the three tenets of cell theory?
- all living things are composed of one or more living cells
- the cell is the basic unit of structure and organization in organisms
- cells arise from pre-existing cells
what are prokaryotic cells?
prokaryotic cells where the first cells, and still exist today, does not have a nucleus, still contains ribosomes, no membrane bound organelles
what are eukaryotic cells?
eukaryotic cells evolved from prokaryotic cells, up to 1000 times larger than a prokaryotic cell, contains a nucleus and membrane bound organelles
differences between eukaryotic cells, and prokaryotic cells?
PROKARYOTIC CELLS:
- has no nucleus
- is significantly smaller
- does not contain any membrane bound organelles
EUKARYOTIC CELLS:
- is up to 1000 times larger than prokaryotic cells
- contains a nucleus
- contains membrane bound organelles
similarities between prokaryotic and eukaryotic cells?
BOTH CONTAIN:
- ribosomes
- a plasma membrane
- a cytoplasm
what is the endosymbiotic cell theory?
states that some of the organelles in eukaryotic cells were once prokaryotic microbes
what is transcription?
the reading of genetic code
what are the nucleus’ functions?
transcription, and the duplication of genetic material prior to cell division
what is the nucleolus?
the area where RNA is produced, and where the ribosomes are made
what are chromosomes?
chromosomes are condensed DNA and proteins coiled into dense structures
what is the nucleoplasm?
the central area of the cell that contains the genetic material
what is the central organelle?
the nucleus
what are ribosomes?
small, dense structures composed of rRNA and proteins
what are bound ribosomes?
bound ribosomes produces protein for export out of the cell
what are free ribosomes?
free ribosomes produces proteins used inside the cell
what is the Endomembrane system?
the Endomembrane system contains structures that work together to synthesize, store, package, and transport materials within the cell
what is rough Endoplasmic Reticulum R.E.R?
a series of interconnected tubular canals connected to the nuclear membrane, the outer surface is covered in ribosomes for production of protein to be exported
what is smooth Endoplasmic Reticulum S.E.R?
has NO ribosomes on the surface, contains enzymes to detoxify drugs and other poisons, associated w/ lipid and steroid production, exists in organs that produce steroids and hormones
what are vacuoles?
vacuoles are membrane covered sacs filled w/ water or waste materials
what is the vacuole’s functions in animal-like
organisms?
digestion and the elimination of excess water
what is the vacuoles function in plants?
stores waste products, helps maintain cell rigidity, forces cytoplasm against cell membrane for better gas exchange
what are vesicles?
vesicles are smaller membrane covered sacs that move materials around and between organelles.
what is the Golgi body?
the Golgi body are elongated membranous sacs used as a temporary storage of materials made in other parts of the cell