NSWTSCN312A- Investigating biological processes
Instructions: This worksheet is to be completed for homework. You must bring the completed worksheet to your Monday class so we can review the answers. This is worksheet will not count towards your final mark, but it may include exercises which will help to prepare you for your tests.
1.
Glossary: Explain the meaning of the biological word or concept listed below. You may use your class notes, a dictionary or the internet.
Biological word or concept
Osmoregulation
Your explanation, find an example
An example of osmoregulation is how plant cell walls prevent further water from entering a cell due to pressure exerted by the cell membrane against the cell wall.
Another example is the regulation of salt concentrations in the bodies of fish to balance out effect of osmosis on the organism.
Can u find your own example?
Homeostasis
Terrestrial ecosystem Ecosystems that exist ‘on land’ as opposed to aquatic ecosystems.
Examples include forests, deserts, grasslands etc.
Endocytosis An example of endocytosis is how bacteria are engulfed by the cell membrane of white blood cells. Can u find another example?
Exocytosis
Homeostasis is the regulation of body systems and functioning within a stable range to support the processes that are necessary to support life.
The maintenance of body temperature is an example, can u find another?
An example of exocytosis is the export of cellular products from the cell via packaging into cell vesicles in the Golgi apparatus of the cell.
Can u find another example?
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Document Owner: GEAP Cooma
Filename: Worksheet for week 8- 25 Mar 2014

2.
Find out how penicillin works to kill bacterial cells. Relate this to what you know about the importance of the cell membrane. What would happen to the cell is the cell membrane was not intact?
Penicillin acts on the cell membrance of bacteria which disrupts to process whereby new cell membrane is formed, and the cell membrane of a bacteria is incomplete. This means the cell cannot regulate the substances that move in and out of the cell and so it dies.
3.
What are examples of passive transport in cells? How does it work?
Passive transport are those processes whereby substances move in and out of cells without using energy made by the body. Examples include diffusion and osmosis, which allow substances to move because of differences in concentrations of those substances (a concentration gradient) in different areas. Substances will move from a higher concentration to a lower concentration until the two concentrations equalise.
4.
Find an example of an adaptation in plants or animals that help prevent water loss or help to conserve water.
Xerophytic plants are adapted to conditions where water can be scarce. Adaptations include leathery leaves (to prevent wilting), fewer stomates, silvery/grey leaf colour to reflect light and heat
(to prevent drying), presence of hairy leaves (to insulate leaves), periods of dormancy or very quick life cycles to make sure seeds are produced at times when it is wet.
Camels have elyptical red blood cells which allow them to go for long periods without water and to remain functioning when their blood becomes more concentrated as they lose water. When they do drink large amounts of water, this results in their blood fluid becoming diluted again relatively quickly. The shape of the red blood cells ensures they do not rupture when high levels of water enters the bloodstream.
5.
What are the different types of active transport mechanisms that facilitate movement of particles in and out of cells. Give an example of each type in a plant or animal cell.
Endocytosis eg: (see above)- see if you can find another example
Exocytosis eg: (see above)- see if you can find another example
6.
Why do we measure a person’s temperature see if they are healthy or not? Why is it important to maintain a specific temperature and what does this indicate about their body function?
A human’s temperature will always be in the range of 35-37 degrees C. If it goes below this they will become hypothermic (and could die). If the temperature increases above 37.5 degrees C this indicates that they have an infection. This condition is known as having a fever.
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Document Owner: GEAP Cooma
Filename: Worksheet for week 8- 25 Mar 2014

7.
Why can a slight ‘fever’ be a ‘good’ thing, despite the fact that it may be outside the range for what is ‘normal’ for a healthy human being?
A slight fever can provide extra warmth to drive body processes as an organism fights the infection.
A slight fever is actually an indication that the body is ‘fighting the disease’. A high fever can be dangerous as it can cause febrile convulsions, which can’t kill you directly but can cause people to pass out and injure themselves, or choke if they have something obstructing their airway. A high fever can increase chances of dehydration which can also be dangerous.
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Document Owner: GEAP Cooma
Filename: Worksheet for week 8- 25 Mar 2014