Excretory and Endocrine Systems Worksheet
1. Name and explain the three processes that result in the formation of urine. Draw a flow chart,
create an outline or draw a diagram that shows the formation of urine. Be sure to name the
important parts of the nephron.
2. Refer to the tables provided to answer the following questions:
a. Based on the table below, are the quantities of each solute expected for a normal
individual? Explain your reasoning. If these results are not characteristics of a healthy
individual, provide a possible explanation for the data.
b. Based on the table below, are the quantities of each solute expected for a normal
individual? Explain your reasoning. If these results are not characteristics of a healthy
individual, provide a possible explanation for the data.
3.
Distinguish between the two methods in which hormones bind to receptor cells.
4.
Majed has been stressed for several days due to overload of work. Describe the long-term
stress response that Majed is experiencing, on the cellular level, using a flow chart. Indicate
the hormones/glands involved and the outcome of these hormones on Majed.
5.
Diabetes is a disease that can be controlled if certain measures are taken.
a. Distinguish between Type 1 and Type 2 diabetes.
b. Explain why most people with diabetes must reduce the amount of carbohydrates
they consume.
c. What potential complications do diabetics face if they do not control their
diabetes?
6.
Outline how hormones play a role in the female reproductive system. Construct a flow chart
to describe the average woman's cycle. Be sure to illustrate the hormones/glands involved
and the outcomes of these hormones.
7.
What is ADH? Explain the feedback system for ADH. Is it negative or positive feedback?
How do you know?
8.
What are performance-enhancing drugs? How do anabolic steroids work? Use a flow chart.
9.
Use the diagram of the female reproductive cycle to answer the following questions.
a. Name hormone 'A' and explain your choice.
b. Name hormone 'B' and explain the significance in the dramatic increase after Day 14.
Excretory and Endocrine Systems Worksheet – ANSWERS
1. Refer to notes
2. a) The results are abnormal because the quantity of protein that was in the glomerulus is also
the same as the one in Bowman’s capsule. This should not occur as normal conditions would
have plasma proteins remain in the blood within glomerulus. High amount of protein in the
urine would indicate a disease of the kidney or a serious illness such as high blood pressure
or heart failure.
b) The results are normal because proteins have not passed through the glomerulus into
Bowman’s capsule as they are too large to do so. The quantity of urea increases as the filtrate
makes it way through the nephron, which is normal (the point of the kidney is to expel wastes
and concentrate the urine which occurs when important substances such as water, ions and
glucose are reabsorbed to be re-used by the body). Additionally, the amount of glucose
decreases as the filtrate passes through the kidney, which is expected as glucose is
reabsorbed to be re-used by the body for energy.
3. Hormones can utilize the protein hormone pathway if they are protein-based (water-soluble)
or the steroid hormone pathway if they are lipid-based (water-insoluble).
 In the protein hormone pathway, the hormone binds to specific receptor proteins on
the cell membrane of the target cell. The receptor proteins change shape in response
to the binding and becomes activated. This then triggers a signal pathway that goes
inside the cell which leads to a cytoplasmic response or expression of a gene.
 In the steroid hormone pathway, the hormone is able to diffuse across the cell
membrane of the target cell as it is lipid-soluble. The hormone binds to specific
receptor proteins in the cytoplasm or nucleus (more common) = forming a hormonereceptor complex. This complex binds to a control sequence on the target gene, either
turning it on or off, which in turns activates or deactivates the gene and controls the
amount of protein being made
4. In long-term stress situations, this stimulus sends a signal to the hypothalamus, which sends a
releasing hormone (CRH – cortisol releasing hormone) that acts on the pituitary. The
pituitary releases ACTH which acts on the adrenal cortex, which in turn releases cortisol.
Cortisol will target cells in liver, muscles and kidney – causing lipids and proteins to break
down into fatty acids and amino acids, which in turn can be metabolized into glucose. This
will increase blood sugar levels, which is important in long-term stress (as you are prone to
metabolizing even more, causing weight loss, etc). This will help restore homeostasis.
5. a) Type 1 diabetes is a disease in which individuals CANNOT make insulin to control blood
sugar levels (insulin decreases blood sugar levels). This type is often diagnosed in young
children and is known as “juvenile diabetes”. Type 2 diabetes is a disease that occurs later in
life, often with individuals who are obese and do not maintain healthy lifestyles. They still
have insulin, just not as much and/or the insulin receptor proteins (to bind to the insulin
hormone) may not function completely.
b) People with diabetes cannot maintain their blood sugar. When you eat a meal, your blood
sugar will increase. You need to have insulin to bring the blood sugar level back down to the
homeostatic set value. Therefore, people with diabetes need to reduce their amount of
carbohydrates consumed as carbohydrates contain glucose.
c) Too much sugar consumed = diabetic coma. Other side effects: fatigue, sweating,
increased urine output, thirstiness, etc.
6. Refer to notes.
7. ADH stands for anti-diuretic hormone that stimulates the kidney to absorb MORE water
from the urine, which increases the volume of the blood. In turn, your urine output decreases.
It is a negative feedback system. For example, if you eat a meal high in salt, your body needs
to compensate for the increase in ion concentration, so it will do so by taking some water
from the urine through the nephron – to balance it out.
8. Performance-enhancing drugs are banned drugs that increase a person’s optimal physical
performance by stimulating something such as muscle mass production or oxygen uptake. An
example is abusing anabolic steroids, which speed up protein production (in turn leads to
more muscle being built). They work by acting as a synthetic lipid hormone which must be
injected or ingested by the person. It will travel in the blood to its target cell and diffuses
across the cell membrane and bind to specific receptor proteins in cytoplasm to form a HRC.
The HRC will diffuse into the nucleus and bind to the DNA segment containing the gene to
make muscle protein. The gene will be turned on, but expressed drastically to the point where
there is a huge amount of muscle protein being formed and the hormone also blocks the
effect of the stress hormone cortisol, preventing any muscle protein from being broken down.
9. a) Hormone A is the luteinizing hormone (LH) because the hormone spikes around Day 14,
signaling the release of a mature egg from the follicle.
b) Hormone B is likely the ovarian hormone progesterone because the formation of the
corpus luteum causes two ovarian hormones to be secreted: estrogen and progesterone
(progesterone in larger amounts). This hormone thickens the uterine lining and prepares for
fertilization of the egg. However if the egg has yet to be fertilized by Day 28, the corpus
luteum degenerates, causing the amount of ovarian hormones to be decreased, as shown in
the graph by Day 28.