9th Grade CELL BIOLOGY (TOPIC 3)

These questions are designed to help you to do well in the Cell Biology Quiz. Make sure that you have worked through the questions in advance, and you should do very well in the Quiz!

1. Outline the 3 tenets of Cell Theory and know the scientists involved in the development of cell theory

2. Identify key components of a light microscope (objective lens, ocular lens, stage, coarse focus, fine focus).

3. Explain why electron microscopes can achieve higher magnification and resolution than light microscopes.

4. Draw a prokaryotic (bacterial) cell and label 4 – 5 key features5. Compare and contrast prokaryotic (bacterial), eukaryotic plant

and eukaryotic animal cells.6. Identify organelles within a eukaryotic animal/plant cell7. Draw and label a plant cell and an animal cell. Include as

many labels as you can. For the plant cell label 10 organelles and in the animal cell label 8 organelles (nucleus, rough endoplasmic reticulum, smooth endoplasmic reticulum, centrioles, vacuoles, Golgi apparatus, ribosomes, mitochondria, chloroplasts, lysosomes)

8. Choose 4 organelles and explain their function using at least 2 complete, grammatically correct sentences.

9. Draw and label a diagram of the cell membrane. Identify the phospholipid bilayer, glycoproteins, (cholesterol), protein channels/pumps/receptors. Label the hydrophobic and hydrophilic regions appropriately.

10. Distinguish between the different cell types: prokaryotic, eukaryotic plant, eukaryotic animal, eukaryotic protistan and eukaryotic fungal nucleus, mitochondrion, chloroplast, rough endoplasmic reticulum.

11. Explain, Compare and contrast diffusion, osmosis, endocytosis and exocytosis, active transport involving protein pumps

12. Analyse data from an osmosis experiment, identify hypertonic, hypotonic and isotonic solutions.

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CELL BIOLOGY

Early microscopes- Antonie Van Leeuwenhoek (1632) Hooke (1665) first used the term cell when looking at cork

under the microscope Compound microscope (two lenses) perfected by Joseph

Jacob Lister (1850). First used the term cell when looking at cork under the microscope

Pasteur disproved spontaneous generation using his swan-necked flasks

Cell theory proposed by Matthias Schleiden (botanist) and Theodor Schwann (zoologist)- Basically- All living things are made of cells, new cells formed by the division of pre-existing ones, the cell contains inherited information for growth and development and that the chemical reactions take place within cells ( the functioning unit of life)

There are two main types of cells: Prokaryotes and Eukaryotes. Prokaryotes are smaller with no membrane bound nucleus and no membrane bound organelles. Eukaryotes have a distinct nucleus and have membrane bond organelles

You should understand how to use scales and magnification factors

Understand and know the main parts of a light microscope:

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Understand that electron microscopes use a beam of

electrons instead of light and the higher resolution is due to the shorter wavelength

Know and understand the main differences between plant/ animal/ bacterial cells

Plant cell

Animal cell

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Know and understand the functions of the main organelles: Nucleus, nucleolus, ribosomes, Golgi apparatus, mitochondria, lysosomes, perioxomes, Rough ER and smooth ER

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ORGANISATION OF MULTICELLULAR ORGANISMS

3.1.2. Organisation of complex (multicellular) organisms : List the levels of organization for multicellular organisms

Define: Tissue; organ; organ system

SPECIALISED CELLS Multicellular organisms (plants and animals) have many

different types of cells Each cell type has a special task and structure Each cell has the same DNA in the nucleus , but only a section

of it is expressed

DEFINITIONS1. Cells are grouped into tissues2. Tissues are grouped into organs3. Organs are grouped into organ systems

Cell

Tissue (a group of cells with common structure and function)

Organ (part of organism with specific vital function)

Organ systems (group of organs working together)

DIFFERENT CELLS HAVE DIFFERENT SHAPES AND DIFFERENT FUNCTIONS

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For example, red blood cells are small, disc shaped and lack a nucleus. This shape is designed to maximize the quantity of haemoglobin (the oxygen carrying molecule) AND allow them to squeeze into narrow blood vessels.

3.3.1 Identify pancreatic exocrine cells as they appear using an electron microscope. Relate the structure of the pancreatic exocrine cell to its function.

Pancreatic cells make many proteins (enzymes and hormones) to export from the cells. For that reason, these cells have a lot of protein-synthesising apparatus (RER, ribosomes, Golgi apparatus) and many secretory vesicles containing the products for export out of the cells.

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3.3.2 Identify small intestinal epithelial cells as they appear using an electron microscope. Relate the structure of the SI epithelial cell to its function.

Cells of the small intestine have many microvilli – which are foldings of the cell membrane – in order to increase the surface area for movement of nutrients by diffusion and active transport into the gut cells.

3.3.3 Identify tracheal epithelial cells as they appear using an electron microscope. Relate the structure of the epithelial cell to its function.

Ciliated epithelial cells in the trachea are able to ‘brush’ mucus, dust and other particles back towards the throat and away from the lungs, in order to prevent them from settling in the delicate gas-exchange tissue of the lungs.

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