EduNinjaThe image was obtained with a mobile phone camera pointing down the eyepiece tube of a light microscope. It shows onion (Allium cepa) epidermal cells after immersion in a hypertonic salt solution during an experiment on osmosis.
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The length of one onion epidermal cell in the micrograph measured by the line Y-Z is 24 mm . Calculate the actual length of this cell in micrometres.
The electron micrograph shows a thin section through a plant mesophyll cell.
What is the magnification of the image?
The micrograph is an image of human cheek cells viewed with a light microscope.
Identify the piece of equipment that is used together with the microscope to measure the size of the cells.
Each small division of the scale in the micrograph is equivalent to .
Calculate the diameter of the cell labelled X .
Calculate the magnification of the image.
Compare and contrast the cell components of eukaryotic and prokaryotic cells.
The image shows epidermis tissue from a bulb of the onion plant (Allium cepa) viewed using a light microscope.
Calculate the magnification of the image.
State the item of equipment that a student could use to accurately measure the length of an onion cell viewed using a light microscope.
Draw a labelled diagram of a nucleus from a eukaryotic cell, such as an onion epidermis cell, as seen using an electron microscope.
The micrographs show two examples of atypical cells.
Aseptate fungal hyphae
Striated muscle fibres
Which feature shared by both types of cells makes them atypical?
Both have cell walls.
Both have several nuclei.
Both lack membrane-bound organelles.
Both are divided into compartments.
The image shows a cast of the lower surface of a leaf from a busy Lizzie (Impatiens walleriana) plant as seen under a light microscope with a magnification of .
State how the magnification of the microscope was calculated.
What feature of both striated muscle and aseptate fungal hyphae is different from typical cell structure?
They have multiple nuclei within a structural unit.
They have a cell wall that is not made of cellulose.
They have plasmids.
They have an absence of cholesterol in the plasma membrane.
The micrograph shows a human cheek cell magnified with a light microscope.
Calculate the width of the cheek cell from X to Y .
Explain what causes the irregular shape of the cheek cells rather than the uniform shape of plant cells.
Which structure found in eukaryotes has a single membrane?
Nucleus
Lysosome
Chloroplast
Mitochondrion
A cell contains chloroplasts, plasma membrane and 80 S ribosomes. What type of cell could it be?
Bryophyte
Lymphocyte
Prokaryote
Neuron