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
what does hydrolytic mean
to break something with water
what are lysosomes?
vesicles containing hydrolytic enzymes
what produces lysosomes?
the Golgi body
what is the mitochondria?
a double membrane structure found in both animal and plant cells
what is the mitochondria’s structure?
the mitochondria’s inner membrane is folded inwards to increase the surface area to maximize sites for chemical reactions
what is the name of the fold in the inner membrane of the mitochondria?
cristae
where are the enzymes located in the mitochondria?
enzymes are located on the cristae of the mitochondria to carry out cellular respiration
what is cellular Respiration?
cellular respiration converts chemical energy found in food (sugars) into a form of energy that can be used by cells
what cells are plastids found?
plastids are only found in plant cells
what are chloroplasts?
chloroplasts are the most common type of plastid, that have a large surface area, containing a coin-like membrane
what are chromoplasts?
chromoplasts are coloured plastids that store accessory pigments, and capture other wavelengths of light to maximize photosynthesis
what are leucoplasts?
leucoplasts are another type of plastid, thats used as a long term storage of sugars (starch) for later use.
what is the cytoskeleton?
the cytoskeleton is a network of fibres that organize structures and activities in the cell
what are microfilaments?
are solid protein fibres that form a lattice throughout the cytoplasm
what are intermediate filaments?
intermediate filaments are fibrous protein strands that holds the nucleus and other organelles in place
what are microtubules?
are used to maintain cell shape
what are cilia and flagella?
cilia and flagella are hairlike projections from cells
what is the purpose of the cytoskeleton?
it is used to help maintain the cell’s shape and distributes cell contents during cell division
