CELL STRUCTURE

The plasma membrane is the boundary between a cell’s internal and external environments. Both environments are aqueous.

To allow this separation of aqueous environments the regions of the plasma membrane indicated in the diagram have the following properties:
1. (X) hydrophilic layers on the outside and (Y) hydrophobic layers on the inside of the membrane
2. (X) hydrophobic layers on the outside and (Y) hydrophilic layers on the inside of the membrane
3. X and Y are both hydrophilic layers
4. X and Y are both hydrophobic layers
Different cell types are shown in the diagram below.

Based on the information in the diagram, it can be concluded that
1. Cell X is a eukaryotic cell because it has flagella but lacks organelles
2. The cells in Y are prokaryotic cell because they have a cell wall
3. Cell Z is eukaryotic because it contains organelles
4. All of the cells are typical sizes for eukaryotic cells
View the diagram representing an image from an electron microscope.

Choose the correct name and description of the structure labelled Q. The structure is
1. The nucleus which controls biochemical reactions occurring in the cell
2. A mitochondrion which produces most of the ATP needed by the cell
3. Golgi apparatus for packaging substances into vesicles for secretion from the cell
4. Endoplasmic reticulum for the transport of substances within the cell
Neurons are a major cell type in the nervous systems of multicellular organisms. Using the information in the diagram choose the correct response.

A neuron is
1. an example of a prokaryotic cell
2. an example of a stem cell
3. an example of a specialised cell
4. always independent of other cells
The diagram represents an image produced by an electron microscope. These structures are visible only in an electron microscope.

Structure Y is
1. a Golgi body
2. smooth endoplasmic reticulum
3. a ribosome
4. rough endoplasmic reticulum
The diagram represents an image produced by an electron microscope. These structures are visible only in an electron microscope.

The function of Structure X is
1. degradation of cellular material
2. lipid production
3. cellular respiration
4. protein synthesis
The diagram represents an image produced by an electron microscope. These structures are visible only in an electron microscope.

A prokaryotic cell would contain
1. both structures X and Y
2. neither structure X nor structure Y
3. structure X but not structure Y
4. structure Y but not structure X
Liposomes can be used to deliver molecules such as drugs or DNA into cells. This occurs when the liposome membrane fuses with the plasma membrane of a cell. The contents of the liposome are delivered to the cytoplasm of the cell. The diagram represents the structure of a liposome carrying drug molecules.

It would be reasonable to expect that
1. Molecule Z would be lipid soluble
2. Liposomes would be repelled by the plasma membrane
3. Molecule Z could freely diffuse out of the liposome
4. Molecule Z would be water soluble
The following diagram represents the common marine bacterium Vibrio fisheri.

The structures labelled X are called
1. Microvilli
2. Axons
3. Flagella
4. Hair cells
The following diagram represents a bacterium in the genus Bdellovibrio.

The function of the structure labelled X is
1. Excretion
2. Locomotion
3. Nutrient uptake
4. Defence from pathogens
A student examined a section of animal intestine and drew the following diagram.

The structure labelled Y is
1. Mitochondria
2. Microvilli
3. Chloroplast
4. Golgi apparatus
A student examined a section of animal intestine and drew the following diagram.

The function of the structure labelled Z is
1. ATP production
2. Protein synthesis
3. Locomotion
4. Nutrient uptake
A student examined a section of animal intestine and drew the following diagram.

The function of structure labelled Y is
1. Movement of nutrients across the gut surface
2. Increased surface area for nutrient uptake
3. Increased surface area for excretion of waste products into the gut
4. Movement of waste products across the cell surface
A student viewed an electron micrograph of neurons in the brain. He drew the following diagram of a synaptic junction.

The function of the structure labelled C is
1. Storage and release of neurotransmitter molecules
2. Energy production by aerobic respiration
3. Energy production by photosynthesis
4. Storage and degradation of cellular waste material
A student viewed an electron micrograph of neurons in the brain. He drew the following diagram of a synaptic junction.

When an electrical impulse arrives at the presynaptic terminal
1. Energy is taken up by structure D
2. Structure C moves into the post-synaptic cell
3. The membranes of pre- and post-synaptic cells make contact
4. Neurotransmitter molecules are released from structure C
Scientists have found microbes living in extreme conditions such as highly saline lakes and boiling hot springs. Many of these microbes have been classified as bacteria. A defining characteristic of a bacterium, a prokaryote, is
1. The presence of a cell wall
2. The absence of a plasma membrane
3. The absence of a membrane bound nucleus
4. The absence of ribosomes
The diagram represents a plant cell as seen through an electron microscope.

A plant cell can be distinguished from animal and fungal cells by the presence of
1. Cytoplasm
2. A cell wall
3. A nucleus
4. Chloroplasts
A student prepared banana cells for viewing under the light microscope. She added iodine to the banana cells before placing a cover slip over the sample and viewing under the microscope.

The purpose of the iodine was to
1. Kill the cells
2. Stain the mitochondria
3. Stain the starch granules
4. Stain the chromosomes
Amoebas are common freshwater unicellular organisms. An amoeba was viewed under the light microscope first in its normal pond water (A) and then in hypotonic (B), hypertonic (C) and isotonic (D) solutions.

Which statement best describes the cell observations as represented in the diagrams?
1. The cells in A are not an appropriate control
2. The cells in B have gained water by osmosis
3. The cells in C have lost water by apoptosis
4. The cells in D have lost water by osmosis
The diagram represents a region of a plasma membrane.

The molecule labelled R most likely represents
1. A channel protein for movement of water-soluble substances
2. The phosphate group of the membrane phospholipid bilayer
3. A protein on the cell surface specifically for cell-cell recognition
4. A channel for lipid-soluble molecules to enter or leave the cell

CELL STRUCTURE

Test your understanding of cell structure with this multiple choice quiz