6 - Cell Structures & Function Flashcards
chapter 7
The nuclear envelope, what is it’s purpose? And is it single membrane, or double?
encloses the nucleus
Double membrane
What is stored in the nucleus?
Chromosomes & information storage
Define the nuclear lamina
it is the fibrous protein shell - strengthens the structure and maintains it’s shape
on the interior chromosomes attach to it
What is in the nucleolus?
Where RNA molecules found in ribosomes are made + small and large ribosomal subunits are made
What is the endoplasmic reticulum?
“inside formed network”
it extends from the nuclear envelope into the cytoplasm
What is different between the rough endoplasmic reticulum and the smooth endoplasmic reticulum?
rough ER - purpose is to synthesize proteins
smooth ER - purpose is to catalyze reactions involving lipids
Describe what the rough endoplasmic reticulum does
makes proteins for - plasma membrane, secreted into the cell exterior, or shipped to an organelle
the ribosomes on the exterior manufacture the proteins the then move inside on the lumen to undergo folding
What are the functions of some of the proteins produced by the rough ER?
- carry messages out to other cells
- act as membrane transport proteins or pumps
- enzymes
Rough ER products are packaged up and shipped out
The smooth endoplasmic reticulum - what is the purpose?
- contains enzymes that catalyze reactions w/ lipids
- could break down lipids
- manufacturing site for phospholipids used in plasma membranes
- reservoir for calcium ions that act as signaling
What is the purpose of the cytoskeleton?
to hold the shape
long polymers of globular proteins
What is the most prominent cell in bacteria?
Chromosome
What is the purpose of ribosomes?
to manufacture proteins
Describe a periosome
single membrane originates from the ER contains transporters for macromolecules Function: oxidizes FA (H2O2) Said to contain: catalase
Describe the Golgi apparatus
for folding and finishing of proteins
cis side close to RER, receiver bay for Proteins from RER
trans surface -> plasma membrane, shipping bay
The smooth ER - describe
contains enzymes to catalyze lipids
manufacturing site for phospholipids -> cell membrane
Reservoir for CA ions
has no ribosomes
Describe glyoxysomes
in plants
oxidizes fats for storage