Eukaryotic cell 1 & 2 Flashcards
cell consists of 2 main components
nucleus and cytoplasm
largest structure
nucleus
nucleus contains
- DNA organized in chromosomes
- nucleoproteins
- newly synthesized RNA
nucleoproteins involved in
DNA and RNA synthesis and folding of DNA
2 forms of DNA in nucleus
heterochromatin and euchromatin
heterochromatin
dark, clumped peripherally, silenced (not involved in RNA synthesis)
euchromatin
light, scattered, actives (involved in RNA synthesis)
nucleus is bound by
nuclear envelope
nuclear envelope
- 2 concentric membranes, - continuous with the ER,
- contains pores to allow movement of substances between nucleus and cytoplasm
- consist of nucleoporins
- become leaky w age
nucleolus
- roughly spherical in nucleus
- involved in ribosomal RNA synthesis and ribosome assembly
nucleolus consists of
- nucleonema; dense, darkly staining, partially assembled ribosomes
- pars amorpha; DNA coding for rRNA
main organelles in cytoplasm
- ER
- golgi apparatus
- ribosomes
- mitochondria
- lysosomes
- centrioles
ER latin
rete means net
ER
network of membranes, connected to nuclear envelope
2 types of ER
what are each involved in
smooth and rough
rough are studded w ribosomes; involved in protein synthesis and modification and packaging of proteins before transport to golgi
smooth; no ribosomes and involved in synthesis and storage of phospholipids, cholesterol, glycerides, glycogen and steroids, also involved in drug detoxification and calcium storage (muscle)
ribosomes are responsible for
protein assembly: structural, chemical messengers, enzymes
increased protein production requires more
ribosomes
ribosomes consist of
rRNA and protein
ribosomes pathway
synthesized in nucleus
assembled in nucleolus
transferred to cytoplasm
ribosomes can be
free (single unit) or poly-ribosomes
*** listen to lec for this part
golgi apparatus consist of
series of membranous sacks called cisternae
golgi apparatus communicates
w ER and cell surface via vesicles
major functions of golgi apparatus include (3)
- modification and packaging of secretory products (hormones and enzymes)
- synthesis of glycoproteins and glycolipids for cell membrane
- packages enzymes for use within the cell
mitochondria shape
sherical to rod-shaped
mitochondria have their own
DNA so can self replicate
mitochondria supply
cell’s energy, numbers proportional to cell’s metabolic activity
mitochondria membrane
- double; outer and inner
- inner folded into cristae to increase SA, site of energy production, ATP formed within matrix (oxidative phosphorylation)
mitochondria evolved from
bacteria that were engulfed by another single-celled organism
allowed a switch from inefficient process of oxidative phosphorylation
all mitochondrial DNA inherited from your
mother
mitochondria also key regulators of
apoptosis (cell death)