Year 9 Science cycle 2 KA

This topic includes lessons on cells, microscopy, atoms, the periodic table and waves. How confident do you feel answering questions about these topics?

• 1 (not confident at all)

• 2 (I might be OK with some questions)

• 3 (Ok on some things, not so much on others)

• 4 (I will probably get most of it right, but might not know some bits)

• 5 (I have a good understanding of these topics)

A eukaryotic cell is...

• a cell with a true nucleus

• a cell without a nucleus
• a cell with only prokaryotic organelles
• a cell with a nucleus but no organelles

Describe the roles of the following cell organelles.

• Site of photosynthesis in plant cells

• Nucleus

• Produces proteins

• Ribosome

• Site of respiration

• Mitochondria

• Regulates the movement of materials in and out of the cell

• Cell membrane

• Controls the cell's activities and contains the genetic material

• Chloroplast

Define the term "specialised cell".

• A cell that can perform any function within an organism
• A cell that is only found in plants
• A cell that is not adapted to any specific function
• A cell that is uniquely adapted to perform a specific function within an organism.

Describe how a root hair cell is adapted for it's role.

• Root hair cells have long projections to increase surface area for absorption.
• Root hair cells have short projections to decrease surface area for absorption.
• Root hair cells have no projections and are smooth for absorption.
• Root hair cells have a hard outer covering to prevent absorption.

The resolution of a microscope refers to...

• the ability to magnify an image
• the color accuracy of the microscope
• the weight of the microscope
• the ability to distinguish between two separate points or objects

Reorder the following steps for microscopy of onion cells

• Add 1-2 drops of iodine to the specimen

• Place the slide on the microscope stage

• Place a thin layer of onion skin on a slide

• Adjust the coarse and fine focus to bring the image into focus

• Change to an appropriate objective lens to increase the magnification

The image of a cell is measure to be 14 mm long when viewed using a x400 magnification. Calculate the actual size of the cell in micrometres. Use the equation:

Image size = Actual size x magnification

Mathematical Equivalence

ON

Explain why iodine solution is added to a sample of cells before microscopy.

• To add flavor to the cells
• To stain the cells and make them more visible under the microscope.
• To make the cells more slippery
• To increase the temperature of the cells

Idenitfy 2 organelles found in a prokaryotic cell but not in a eukaryotic cell.

• Plasmid and slime capsule

• Mitochondria and ribosomes

• Mitochondria and nucleus

• Chloroplasts and cell wall