Ch. 1 Homeostasis and Organelles

Place the following in correct sequence from simplest to most complex:

Atoms, Molecules, Cells, Tissue, Organs

Identify the organelle that is responsible for cell shape.

Cytoskeleton

A good example of a positive feedback mechanism would be

Enhancements of labor contractions

Identify the organelle that is responsible for modifying and packaging proteins.

Golgi

Which of the following statements is the most correct regarding homeostatic imbalance?

It is considered the cause of most diseases (pathology)

Identify the organelle that is responsible for hydrolyzing material that was brought into the cell.

Lysosome

Identify the organelle that is responsible for increasing surface area of the cell membrane.

Microvilli

Identify the organelle that is responsible for aerobic respiration.

Mitochondria

While taking this exam you used up a lot of energy to write and think, therefore your plasma glucose levels. The alpha cells of the pancreas monitor the plasma glucose levels and they secrete glucagon when the plasma levels are low. Glucagon can then travels to the liver causing the liver to increase the rate of two processes: glycogenolysis and gluconeogenesis. The final product of these two processes is glucose, that gets secreted into the blood plasma. Identify the type of feedback mechanism that regulates plasma glucose levels:

Negative Feedback

A structure that is composed of two or more tissue types that work together to perform specific functions for the body is a(n)

Organ

Some of the nerve endings in the skin are sensitive to changes in temperature. They are part of a negative feedback mechanism regulating body temperature. These nerve endings represent a(n) ________ in the negative feedback mechanism.

Receptor

Homeostasis is the condition in which the body maintains

Relatively stable internal environment, within limits

Identify the organelle that is responsible for protein synthesis.

Ribosome

Identify the organelle that is responsible for protein synthesis.

Rough endoplasmic reticulum

Identify the organelle that is responsible for synthesizing fats.

Smooth Endoplasmic Reticulum (SER)

Generally, what is the result of the negative feedback process?

To maintain homeostasis

It is important for any organism to maintain its boundaries, so that it's internal environment remains distinct from the external environment surrounding it

True

Positive feedback mechanisms tend to enhance the original stimulus so that the response is accelerated.

True

Without some sort of negative feedback mechanism, it would be impossible to keep our body chemistry in balance.

True

Positive feedback differs from negative feedback because

positive feedback tends to enhance the triggering stimulus while negative feedback tends to return the body to a homeostatic balance or "ideal" level