Organelle (2) Flashcards
How are prokaryotic and eukaryotic cells similar?
- contain DNA, ribosomes, semifluid substance called cytosol
What is the structure and function of ribosomes (free vs bound)
- free ribosomes in cytosol make proteins that stay in the cytosol
- bound ribosomes on the outside of the ER or the nuclear envelope make proteins that will be exported or will become plasma membrane proteins
What is the structure and function of endoplasmic reticulum (smooth vs rough)
Smooth ER, lacks ribosomes
- enzymes create lipids, metabolize carbs, and detoxify drugs and poisons
- stores calcium ions (holds them hidden from cytoplasm until they are used to cause a change within the cell)
Rough ER, surface studded with ribosomes
- bound ribosomes secrete glycoproteins (proteins bonded to carbs)
- distributes transport vesicles
- a membrane factory for the cell
What is the structure and function of the golgi
- flattened membranous sacs called cisternae
- modifies products of the ER
- creates certain macromolecules
- sorts and packages materials into transport vesicles
What is the structure and function of lysosomes
- membranous sac of hydrolytic enzymes
- digests macromolecules
- lysosomal enzymes work best in the acidic environment of the lysosome
What is the structure and function of vacuoles
- large vesicles derived from the ER and golgi apparatus
-food, contractile (pump excess water out of cells), (hold organic compounds and water)
What is the structure and function of vesicles
- transfer proteins around the cell
- is a secretory protein surrounded by membranes
What is the structure and function of mitochondria
- sites of cellular respiration (uses oxygen to make ATP)
- double membrane, have free ribsomes and circular DNA molecules
- grow and reproduce independently in cells
What is the structure and function of chloroplasts
- sites for photosynthesis
- double membrane, have free ribsomes and circular DNA molecules
- grow and reproduce independently in cells
- have stoma and thylakoids in granum
What is the structure and function of the nucleus
- contains most of the DNA in a eukaryotic cell
- controls the cells activities
- nuclear envelope, inner and outer membrane, nuclear pores and nuclear lamina
- nuclear interior, made of proteins
- DNA is organized into chromosomes which each contain a chromatin
What is the structure and function of the cell membrane
- regulates transport of materials entering and exiting the cell
- also called the plasma membrane, consists of lipid bilayer
Pathway of a protein produced by bound ribosomes on rough ER
Rough ER –> creates the protein
vesicles –> takes it to the golgi
golgi –> modifies the protein
vesicles –> takes them out or in the cell
Together they synthesize and isolate proteins for use within or outside the cell
What is the endosymbiotic theory
Simply –> mitochondira and chloroplasts share a common ancestor despite being from animals and plants.
- an early ancestor of eukaryotes engulfed an oxygen-using non photosynthetic prokaryotic cell
- engulfed cell formed a relationship with the host cell, becoming an endosymboint
- gets double membrane from cell membrane
What evidence supports the endosymbiotic theory
Chloroplasts and mitochondria have similar structure and have many similar parts
Why can’t cells be really large (surface area - volume ratio)
- larger cells have a smaller surface area to volume ratio
- this means nutrients and water can’t diffuse into the cell fast enough to keep it alive
- can’t get what it needs
- this is way some organelles have a special structure to increase surface area
