Chapter 4 Flashcards
What is the purpose of ribosomes
Carry out protein synthesis
What happens in the nucleolus
rRNA is transcribed and ribosomes are assembled
What happens as cell size increases
Diffusion becomes more inefficient
What is the purpose of a cytoskeleton
Protein fibers support cell shape and anchor organelles
What does chloroplast do
Synthesizes glucose by capturing light’s energy through thylakoid membranes which are arranged in stacks called grana
What do molecular motors do
Move vesicles along microtubules with motor proteins kinesin and dynein
What defines cell shape
Cytoplasm
What makes up a prokaryotic cell
DNA, ribosomes, cytoplasm, plasma membrane, cell wall
What is the structure of eukaryotic flagella
9+2 structure
What is cell crawling
Actin polymerization forces cell membrane forwards and myosin pulls it forwards
What are intermediate filaments
Non moving proteins
What is the Golgi apparatus
Received vesicles from ER, modifies, packages and transports molecules
What is the nuclear envelope
2 phospholipid bilayers, outer layer is continuous with ER
How many chromosomes does a prokaryotic cell have
1
What is the purpose of nuclear pores
Allows the exchange of small molecules
What do actin/ micro filaments do
Long thing polymers involved in cell movement
What is the endoplasmic reticulum
Creates channels and passages within the cytoplasm
What is cristae
Mitochondria’s inner membrane is folded into layers
What is the endosymbiosis theory
Mitochondria and chloroplasts were prokaryotes until a cell ate them
What is the cell theory
All organisms are composed of one or more cells
Cells come from preexisting cells
Cells are the unit of life
What do prokaryotic and eukaryotic cells have
Centrally located DNA
Cytoplasm
Plasma membrane
What is missing from a prokaryotic cell
Nucleus
Membrane bound organelles
Internal membrane system
What do mitochondria and chloroplast have in common
Double membranes
Contain their own DNA
Independently divide
What molecule doesn’t cross the nuclear membrane
DNA
