Assignment 1 70.5 Georgette
Gibas – Bio 235
Weight: 5%
Minimum Pass Grade: 50%
BIOL 235-
Each question is worth 10 marks.
1. Maintenance of calcium ion homeostasis is critical to neurological, cardiac
and skeletal muscle function. Consider the roles of two hormones involved
in the regulation of the concentration of calcium ions in the blood.
Parathyroid hormone increases the concentration of calcium ions in the
blood, while calcitonin decreases the concentration. Based on this
information predict the body’s response to restore calcium balance if a
person swallowed 100 antacid tablets made of a calcium compound in 10
minutes. Include in your answer the definition of homeostasis, the type of
feedback loop involved and all of the components of a feedback loop.
1. Homeostasis – the balance or equilibrium in the body’s internal environment
produced by the body’s regulatory processes.FYI homeostasis: as
maintenance of body conditions within acceptable limits as ‘equilibrium’ for a
cell is death
2. the body might also send signals to block the action of parathyroid
hormone because the calcium levels are already too high.
3. there must be a way for the body to get rid of the extra calcium in the blood.
4. two possibilities are putting more calcium into the bones or excreted more
calcium out of the body through the urine or feces..
the cells that put calcium into the bone or release it into the urine or feces
would be the effectors in the case described here
In this crisis, the type of feedback loop would be a negative feedback system.
This is because a negative feedback system reverses a change in a controlled
condition. An ideal homeostasis would be the maintenance of calcium ions in
the body, but in this case a person who swallows 100 antacid tablets would
Assignment 1 :: Biology 235: Human Anatomy and Physiology 1
, disrupt the homeostasis by increasing the calcium compounds in the body.
With this, the body would have to reverse the disruption by using the feedback
loop. The components of the negative feedback loop would be:
I. The stimulus, which is the 100 swallowed antacid tablets disrupting
homeostasis and controlled condition.
II. With this, the receptors (thyroid gland) will sense the disruption causing
the receptor to send inputs through the nervous system using nerve
impulses to the control center.
III. The control center then, which is the endocrine system, sends output
(release of calcitonin) to the effector to start negating the effects of the
100 antacid tablets.
IV. The effector (which is to inhibit the activity of osteoclasts) then uses the
hormone calcitonin to decrease the concentration of calcium.
V. From the effector, the body responses may be that, the blood speeds up
calcium ion uptake by the bones, and accelerates calcium ion deposition
into the bones. By doing this, calcitonin is able to effectively decrease
calcium and return it back to homeostasis. 6
2. Provide one important example (in the human body) of each of the
following:
a. a molecule containing ionic bonds
sodium chloride - NaCl
b. a molecule containing covalent bonds
oxygen – O2
c. a molecule containing hydrogen bonds
Hydrogen molecule – H2 no this is a covalent bond? Also no function in the
body
What is the function of each of these three molecules you have identified in
the human body? Explain why each of these three molecules must have its
specific types of bonds in order to perform that molecule’s function.
Ionic bonds are most commonly found in teeth and bones, not sodium
chloride?where they give strength to these structural tissues. Sodium Chloride
Assignment 1 :: Biology 235: Human Anatomy and Physiology 2
, (NaCl) specifically is used in the body in many ways such as: maintain a
balance of body fluids, contraction and relaxation of muscles, blood pressure
maintenance, absorption and transportation of nutrients and transition of nerve
signals. How? Explain why each of these three molecules must have its
specific types of bonds in order to perform that molecule’s function.
ionic bonds are weak enough to permit dissociation into ions
- covalent bonds would be too strong to release these ions into solution while
hydrogen bonds would be too weak to maintain the integrity of these
molecules (i.e., hydrogen bonds cannot bind atoms together to form
molecules)
Sodium chloride dissociates into Na+ and Cl- which are used
to carry charges in the body’s electrophysiological systems
Covalent bonds are the most common chemicals in the body and forms most
of the body structures.
Oxygen is important as it fuels the body and uses gas exchanges in the lungs
and blood vessels to sustain life. It is also needed for cellular respiration
period at the end of a sentence
covalent bonds are strong bonds that maintain the integrity of these molecules;
-the other types of bonds are so weak that they would allow these
molecules to break apart too easily
-Consider the MACROMOLECULES of the body – they
are all covalently bonded or we would dissolve.
*oxygen’s only function is as the final electron acceptor and here
it is ½ O2 and therefore the covalent bond is irrelevant
Assignment 1 :: Biology 235: Human Anatomy and Physiology 3
Gibas – Bio 235
Weight: 5%
Minimum Pass Grade: 50%
BIOL 235-
Each question is worth 10 marks.
1. Maintenance of calcium ion homeostasis is critical to neurological, cardiac
and skeletal muscle function. Consider the roles of two hormones involved
in the regulation of the concentration of calcium ions in the blood.
Parathyroid hormone increases the concentration of calcium ions in the
blood, while calcitonin decreases the concentration. Based on this
information predict the body’s response to restore calcium balance if a
person swallowed 100 antacid tablets made of a calcium compound in 10
minutes. Include in your answer the definition of homeostasis, the type of
feedback loop involved and all of the components of a feedback loop.
1. Homeostasis – the balance or equilibrium in the body’s internal environment
produced by the body’s regulatory processes.FYI homeostasis: as
maintenance of body conditions within acceptable limits as ‘equilibrium’ for a
cell is death
2. the body might also send signals to block the action of parathyroid
hormone because the calcium levels are already too high.
3. there must be a way for the body to get rid of the extra calcium in the blood.
4. two possibilities are putting more calcium into the bones or excreted more
calcium out of the body through the urine or feces..
the cells that put calcium into the bone or release it into the urine or feces
would be the effectors in the case described here
In this crisis, the type of feedback loop would be a negative feedback system.
This is because a negative feedback system reverses a change in a controlled
condition. An ideal homeostasis would be the maintenance of calcium ions in
the body, but in this case a person who swallows 100 antacid tablets would
Assignment 1 :: Biology 235: Human Anatomy and Physiology 1
, disrupt the homeostasis by increasing the calcium compounds in the body.
With this, the body would have to reverse the disruption by using the feedback
loop. The components of the negative feedback loop would be:
I. The stimulus, which is the 100 swallowed antacid tablets disrupting
homeostasis and controlled condition.
II. With this, the receptors (thyroid gland) will sense the disruption causing
the receptor to send inputs through the nervous system using nerve
impulses to the control center.
III. The control center then, which is the endocrine system, sends output
(release of calcitonin) to the effector to start negating the effects of the
100 antacid tablets.
IV. The effector (which is to inhibit the activity of osteoclasts) then uses the
hormone calcitonin to decrease the concentration of calcium.
V. From the effector, the body responses may be that, the blood speeds up
calcium ion uptake by the bones, and accelerates calcium ion deposition
into the bones. By doing this, calcitonin is able to effectively decrease
calcium and return it back to homeostasis. 6
2. Provide one important example (in the human body) of each of the
following:
a. a molecule containing ionic bonds
sodium chloride - NaCl
b. a molecule containing covalent bonds
oxygen – O2
c. a molecule containing hydrogen bonds
Hydrogen molecule – H2 no this is a covalent bond? Also no function in the
body
What is the function of each of these three molecules you have identified in
the human body? Explain why each of these three molecules must have its
specific types of bonds in order to perform that molecule’s function.
Ionic bonds are most commonly found in teeth and bones, not sodium
chloride?where they give strength to these structural tissues. Sodium Chloride
Assignment 1 :: Biology 235: Human Anatomy and Physiology 2
, (NaCl) specifically is used in the body in many ways such as: maintain a
balance of body fluids, contraction and relaxation of muscles, blood pressure
maintenance, absorption and transportation of nutrients and transition of nerve
signals. How? Explain why each of these three molecules must have its
specific types of bonds in order to perform that molecule’s function.
ionic bonds are weak enough to permit dissociation into ions
- covalent bonds would be too strong to release these ions into solution while
hydrogen bonds would be too weak to maintain the integrity of these
molecules (i.e., hydrogen bonds cannot bind atoms together to form
molecules)
Sodium chloride dissociates into Na+ and Cl- which are used
to carry charges in the body’s electrophysiological systems
Covalent bonds are the most common chemicals in the body and forms most
of the body structures.
Oxygen is important as it fuels the body and uses gas exchanges in the lungs
and blood vessels to sustain life. It is also needed for cellular respiration
period at the end of a sentence
covalent bonds are strong bonds that maintain the integrity of these molecules;
-the other types of bonds are so weak that they would allow these
molecules to break apart too easily
-Consider the MACROMOLECULES of the body – they
are all covalently bonded or we would dissolve.
*oxygen’s only function is as the final electron acceptor and here
it is ½ O2 and therefore the covalent bond is irrelevant
Assignment 1 :: Biology 235: Human Anatomy and Physiology 3
