SEF031 Form and Function in Biology – Model Answer
What is homeostasis, and describe how blood glucose levels are
maintained.
Bullet points below should be covered for a complete answer. GIVE A % MARK
EQUIVALENT TO THE GRADE CATEGORY AS OUTLINED ON THE LAST PAGE.
•
Homeostasis is the maintenance of stable conditions in an internal environment.
Physiological systems are controlled by the nervous and endocrine systems.
Regulation of the internal environment requires information.
Types of information necessary for physiological systems:
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Set point: a reference point
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Feedback information: what is happening in the system
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Error signal: any difference between the set point and feedback information
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Effectors of systems effect changes in the internal environment.
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Effectors are controlled systems because they are controlled by regulatory systems.
•
Regulatory systems:
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Obtain, integrate, and process information
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Issue commands to controlled systems
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Contain sensors to provide feedback information that is compared to the set point
•
Sensory information in regulatory systems includes:
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Negative feedback
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Positive feedback
•
Feedforward information
Glucose regulation
•
Insulin is released by the pancreas during the absorptive period, when blood glucose
rises.
•
Insulin promotes uptake and utilization or storage of glucose.
•
It acts in skeletal muscle, adipose tissue, and in the liver.
•
Blood glucose falls in the postabsorptive period.
•
Insulin release is lower and glucose uptake is slowed.
•
If glucose level is very low, glucagon is released and causes the liver to break down
glycogen and begin gluconeogenesis.
• Concluding paragraph
SEFP Marking Criteria
For some assessments that are not based on numerical problems, letter grades will be
awarded and the following criteria will be used to assign grades.
Grade
A
70-100%
83%
B
60-69%
65%
C
50-59%
55%
D
45-49%
48%
E
40-44%
43%
F
30-39%
27%
Coursework
Examinations
More specific to this essay
! Addresses the question(s) fully, well
researched.
! Wide range of references.
! Very clear and accurate written expression
! Logical structure and organisation of
material
! Demonstrates a thorough understanding of
the topic.
! No grammatical errors (or almost none)
! Excellent presentation
! Almost complete answer
! Well structured answer
all of bullet points
and evidence
! Includes
Clearly demonstrating
an excellent
ofunderstanding
outside reading
of the subject.
! Good evidence of background reading
fromneed
several
Only
Lifesources.
book reference
! An adequate answer to the question(s)
covering the main points.
! Satisfactory range of references used.
! Demonstrates a good understanding of the
topic with no significant errors.
! Good written expression
! Very few grammatical errors.
! Well organised
! Understands the issues fully.
! Maybe
Major one
points
clearly.missing.
ormade
two points
! Evidence of background reading.
Only need Life book reference
Some factual errors
Limited ranges of references used
Some irrelevant material included.
Satisfactory organisation of material.
Some errors in written English.
! A correct answer based largely on
answers given in lectures.
Three
or four of the key bullet points
! Not all relevant points covered.
! missing
Use of literature/data or adequate
treatment of incomplete data/literature.
! Limited reference to other material.
! Basic approach with little detail.
! Significant errors and/or irrelevant
information.
! Very little evidence of use of references.
! Significant errors in written English.
! Muddled organisation.
! Based entirely on lecture material but
poor structure.
! Significant errors/misunderstanding.
six points
! Four
Littletoevidence
of missing
understanding.
!
!
!
!
!
!
!
!
!
Limited evidence of reading or thought.
Superficial un-analytical approach.
Lacking in organisation.
Poor written English
! Significant conceptual errors.
More than 6 points missing
! Does not demonstrate understanding of
topic.
!
!
!
!
Short but some relevant content.
Poor presentation.
Few or no references.
Poor written English
! Very short answer.
! Very few relevant points.
F
15-29%
! Inadequate or largely irrelevant answer(s).
! Little or no references.
! Poor presentation.
! Most points irrelevant to question.
F
0-14%
! Answer irrelevant to title.
! No referencing.
! Poor presentation.
! Largely irrelevant/incorrect answer.