Cells Flashcards
(14 cards)
Nucleus
-Double membrane
-Stores DNA
Nuclear pores allow RNA and ribosomes to pass through
Mitochondria
-Double membrane
-Where ATP is made
-Inner membrane (cristae) folded for increased SA for respiration
-
Lysosomes
-Contains digestive enzyme to break down pathogens, old organelles, dead cells
Rought endoplasmic reticulum
-Site of protein synthesis
-Folded for large SA
-Studded with ribosomes
Smooth endoplasmic reticulum
-Synthesis, stores and transports lipids and carbohydrates
-Folded for large SA
Golgi apparatus
-Modifies proteins
-Package + transports proteins in Golgi vesicles to release at the membrane
Ribosomes
-Site of protein synthesis
-80s in eukaryotic cells
-70s prokaryotic cells, mitochondrial
Chloroplasts
-Double membrane
-site of photosynthesis
-In plants & algae
Cell vacuole
-Maintains structure, keeps cell turgid
-Temporary energy storage
cell wall
-Provides support + strength
-Cellulose microfibrils
-Fungle= chitin + glycoprotein
-Algae= glycoprotein + cellulose
How eukaryotic and prokaryotic cells differ
Eukaryotic
-Larger
-Membrane-bound organelles
-DNA is linear and in a nucleus
-80s ribosome
Prokaryotic
-Smaller
-DNA is circular and loose or in plasmids
-Has a capsule and flagellum
-Has smaller 70s ribosomes
Specialisation of eukaryotic cells
-Change in structure
-The organelles the cell contains
E.g. Red blood cells biconcave and have no nucleus, Larger SA and more space inside for O2
Sperm cells
Function: Reproduction -
Adaptations:
-Nucleus contains half the normal number of chromosomes
-Contains digestive enzymes to break down the outer layer of an egg cell, to fuse with the egg’s nucleus
-Packed with mitochondria to release energy for the tail movement
-Tail rotates, propelling the sperm cell, allowing it to move towards the egg
How prokaryotic DNA is different
- Circular DNA
- Not associated with histones
