B2.2 Organelles and compartmentalisation
Understandings:
Form and function
Cells
B2
HL
Key words:
Mitochondria
Respiration
Cristae
Matrix
Inner membrane
Outer membrane
Intermembrane space
Chloroplast
Thylakoid
Granum
Lamella
Starch granules
Stroma
Thylakoid lumen
Nuclear pore
Ribosome
Rough endoplasmic reticulum
Golgi apparatus
Cis
Trans
Vesicles
Cargo
Receptor
Clathrin
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B2.2.4—Adaptations of the mitochondrion for production of ATP by aerobic cell respiration
Cristae - folds of the inner membrane of the mitochondria
Ribosomes - area of protein synthesis in mitochondria
Mitochondrial DNA - circular DNA unique to the mitochondria (resembles bacterial DNA)
Matrix - inside the inner membrane of mitochondria, where the Krebs Cycle occurs
Inner membrane - space where the electron transport chain occurs in the mitochondria
Outer membrane - membrane that is in contact with the cytosol of the cell that mitochondria is located in
Intermembrane space - space between outer and inner membrane
Copy and add the following labels
What is the benefit of having cristae?
What is the benefit of having cristae?
Increase surface area for ETC
B2.2.5—Adaptations of the chloroplast for photosynthesis
Thylakoid - A flattened membrane sac inside the chloroplast, used to convert light energy into chemical energy. Where "light reactions" take place
Granum - stack of thylakoids
Lamella - tubes that connect the granum
Chloroplast DNA - non-nuclear DNA; endosymbiosis theory that chloroplasts evolved from free living prokaryotes
Ribosomes - site of protein synthesis
Starch granules - storage of starch/sugar from photosynthesis
Inner membrane - innermost cell membrane of chloroplast
Intermembrane space - space between inner and outer membrane
Outer membrane - membrane of chloroplast that is in contact with the cytosol of plant cell
Stroma - liquid portion of chloroplast where Calvin Cycle (light independent reactions) take place
Thylakoid lumen - space inside the thylakoid where light reactions occur.
Copy and add the following labels
What is the benefit of having grana?
What is the benefit of having grana?
Increase surface area for light dependent reactions
B2.2.6—Functional benefits of the double membrane of the nucleus
The double membrane allows large nuclear pores to form
Where are ribosomes made?
Where are ribosomes made?
Nucleolus
How do ribosomes get out into the cytoplasm?
Where are ribosomes made?
Nucleolus
How do ribosomes get out into the cytoplasm?
Through nuclear pores
What else needs to travel through nuclear pores?
Where are ribosomes made?
Nucleolus
How do ribosomes get out into the cytoplasm?
Through nuclear pores
What else needs to travel through nuclear pores?
mRNA travel out
Histone proteins, transcription factors… travel in
During mitosis and meiosis the nuclear membrane must break down to allow chromosomes to be pulled to separate poles of the cell.
A double membrane can easily form vesicles that move away.
B2.2.7—Structure and function of free ribosomes and of the rough endoplasmic reticulum
What are the two different sizes of ribosomes and where are they found?
Ribosomes are made of proteins (blue) and rRNA (orange and yellow)
Proteins destined for cytoplasm are made on free ribosomes
Proteins destined for outside cell or to be transported within the cell are made on ribosomes embedded in rough endoplasmic reticulum
B2.2.8—Structure and function of the Golgi apparatus
Made of flattened sacs of membrane (cisternae)
Cis face - faces ER
Trans face - faces plasma membrane
Processing and secretion of proteins
Protein processing
E.g.
Adding carbohydrates - glycoprotein
Adding other groups eg. phosphate or sulphur
Assembling quaternary structure
B2.2.9—Structure and function of vesicles in cells
Vesicles can be used to move substances or transport lipid bilayer
Endocytosis
Endocytosis is an active process that involves
“Cargo” - that which is being taken in
Receptor molecules - that bind to the cargo
Clathrin - that coats the vesicle
Clathrin
Can you…
Describe the structure of mitochondria?
Describe the structure of chloroplasts?
Describe the benefits of having a double nuclear membrane?
Describe structure and function of ribosomes?
Describe structure and function of golgi apparatus?
Describe how clathrin is involved in vesicle formation?