Practise IB Biology HL B2.2 by linking compartmentalization, nuclear gene expression and protein pathways to organelle structures for respiration and photosynthesis.
Testis cells are eukaryotic cells. Identify the structures seen under the electron microscope in testis cells that are not present in prokaryotic cells.
The structure of membranes allows them to carry out many functions in cells.
Discuss the use of membranes for compartmentalization in eukaryotic cells.
The electron micrograph shows part of a cell including a mitochondrion.
Outline how the structures labelled X and Y are adapted to carry out the function of the mitochondrion.
X:
Y:
The image shows part of a chloroplast and was produced by electron tomography.
What is the name of I and which reactions of photosynthesis occur in II?
Name of I
Reactions in II
Matrix
Light-independent reactions
Stroma
Light-independent reactions
Matrix
Light-dependent reactions
Stroma
Light-dependent reactions
What is a benefit of double membranes surrounding the nuclei of eukaryotic cells?
They reduce the surface area of the nucleus.
They can easily break down into vesicles during mitosis.
Hydrophilic phospholipid tails can be kept away from the cytoplasm.
Pores are formed to allow movement of DNA from the nucleus to the cytoplasm.
Outline what happens to the proteins produced by free and bound ribosomes.
Free ribosomes:
Bound ribosomes:
In the electron photomicrographs which organelle is involved in vesicle formation?
What is the role of clathrin molecules in the formation of vesicles?
Facilitate transport of sodium and potassium ions
Bind together to help the membrane become indented
Adhere to the phospholipid bilayer to increase fluidity
Create a concentration gradient for uptake of substances into vesicles