Cell Structures Flashcards
plasma membrane
Description
composed mainly of
outer layer of the cell, composed mainly of lipids and proteins
plasma membrane
Function
- encloses the cell contents
- regulates what enters and leaves the cell
participates in - growth, reproduction, and interactions between cells
microvilli
(mi-kro-VIL-i)
Description
short extensions of the cell membrane
microvilli
(mi-kro-VIL-i)
Function
absorb materials into the cell
nucleus
Description
- large
- membrane-bound,
- darkstaining organelle
- near the center of the cell
nucleus
Function
makes ribosomes
cytoplasm
Description
colloidal suspension that fills the cell from the nuclear membrane to the plasma membrane
cytoplasm
Function
What does cytoplasm consists of?
site of many cellular activities; consists of cytosol and organelles
colloidal suspension
mixtures in which microscopically dispersed insoluble particles of one substance are suspended in another substance.
cytosol
Description
fluid portion of the cytoplasm
cytosol
Function
surrounds the organelles
endoplasmic reticulum (ER)
Description
network of membranes within the cytoplasm; rough ER has ribosomes attached to it; smooth ER does not
endoplasmic reticulum (ER)
Function of rough ER
rough ER modifies, folds, and sorts proteins;
endoplasmic reticulum (ER)
Function of smooth ER
lipid synthesis
ribosomes
Description
composedof
- small bodies free in the cytoplasm
- or attached to the ER
- composed of RNA and protein
ribosomes
Function
manufacture proteins
How many chromosomes are in each human cell
46 chromosomes in each human cell
except egg and sperm cells
Golgi apparatus
Description
layers of membranes
Golgi apparatus
Function
- modifies proteins
- sorts and prepares proteins for transport to other parts of the cell or out of the cell
mitochondria
Description
large organelles with internal folded membranes
mitochondria
Function
convert energy from nutrients into ATP
lysosomes
Description
small sacs of digestive enzymes
lysosomes
Function
digest substances within the cell
peroxisomes
(per-OKS-ih-somz)
Description
membrane-enclosed organelles containing enzymes
