Ch. 4 Flashcards
(34 cards)
Magnification
increase in the apparent size of an object
cell theory
all living things are composed of cells, all cells come from other cells)
Light and Electron microscopes
used to magnify objects
Scanning electron microscope
SEM
used to study surfaces of cells *to remember: ss, scanning surfaces
Transmission electron microscope TEM
used to study inside of cells
The smaller you are…the____ the surface volume you occupy..
the larger the surface area volume you occupy
smaller cells have larger surface to volume ratios
plasma membranes
form boundaries between the living cell and its surroundings (makes it flexible)
Chromosomes
filled with DNA
Ribosomes
structural unit for DNA, makes proteins
Cytoplasm
fluid filled with nutrients, in the interior of cell
Prokaryotic cells
no membrane bound organelles
Nucleoid (DNA coiled in a region w/o a membrane)
Eukaryotic cells
have partitions,
organelles perform specific functions which sum up to cellular respirations
Nucleus
genetic control center
contains most of DNA
directs protein synthesis
Ribosomes
does the work in the nucleus,
can read 3 sections of DNA at a time
carry out protein synthesis
Endomembrane system
major manufacturing site
Smooth endoplasmic reticulum (ER)
synthesize lipids *to remember: SS smooth synthesizes
rough endoplasmic reticulum (ER)
makes membrane; Lipid synthesis; detoxification in liver cells; calcium ion storage
mitochondria
convert chemical energy from food (sugar) to ATP
carry out cellular respiration
cristae
folds in the mitochondrion
chloroplasts
in plants, site of photosynthesis
stroma
contains DNA and ribosomes
Thylakoids
sacs inside the chloroplasts, when stacked are called GRANA
Endosymbiont Theory
mitochondria and chloroplasts were prokaryotes with DNA, at some point began living within larger cells
Cytoskeleton
helps organize,
network of fibers,
provide structural supports and cell mobility