Understanding Target Cells, Hormone Mechanisms, and Hormonal Interactions What is meant by the term target cells?

A target cell has a receptor that hormones bind and act on. A target cell has receptors specific to the hormone (Patton & Thibodeau, 2018).

How are steroid hormones able to pass through the cell’s plasma membrane easily?
Lipids such as cholesterol and phospholipids make up the steroid hormones. These lipids are fat-soluble and easily diffuse across the cell membrane of the target cells and bind with receptors found in the cytoplasm (Patton & Thibodeau, 2018).

Name some of the different general types of Non-steroid hormones. Give an example of each.
Amino acid derivatives- Tyrosine and tryptophan (Patton & Thibodeau, 2018)

Peptide hormones- Oxytocin and Somatostatin (Patton & Thibodeau, 2018)

Proteins- Prolactin and insulin (Patton & Thibodeau, 2018).

Glycoproteins- Follicle-stimulating hormone and luteinizing hormone (Patton & Thibodeau, 2018)

Name some ways in which hormones can work together to regulate a tissue.
The first way is synergism, in which two hormones work together to have a greater effect than their individual effects on the cell (Patton & Thibodeau, 2018). The second way is permissiveness, in which a small amount of one hormone allows another hormone to exert its full effect (Patton & Thibodeau, 2018). The third way is antagonism, in which one hormone elicits the opposite effect of another hormone (Patton & Thibodeau, 2018).

Why are Prostaglandins (PGs ) sometimes called tissue hormones?
Prostaglandins (PGs ) are sometimes called tissue hormones because they elicit their action in neighboring cells of the tissue in which they are secreted (Patton & Thibodeau, 2018)

Why are PGs considered to be important in Clinical application?
PGs are considered important in Clinical application because they are found in almost all body tissues and can regulate hormonal activity on the cellular level (Patton & Thibodeau, 2018).

What are the two main divisions of the Pituitary Gland called?
The two main divisions of the Pituitary Gland are Adenohypophysis, which has regular endocrine tissue, and neurohypophysis, which has neurosecretory tissue (neurohypophysis) (Mader & Windelspecht, 2017)

Name three hormones produced by adenohypophysis and give their main functions.
Prolactin – stimulates mammary glands to secrete milk

Growth hormone – promotes bodily growth

Luteinizing hormone- stimulates the growth of the corpus luteum (Patton & Thibodeau, 2018)

What is a tropic hormone? A releasing hormone?
A tropic hormone is a hormone that targets other endocrine glands, while a releasing hormone is a hormone that regulates the synthesis or release of the anterior pituitary gland hormones (Patton & Thibodeau, 2018)

Name the two hormones of the neurohypophysis
Oxytocin

Anti-diuretic hormone (Patton & Thibodeau, 2018)

Where is the thyroid located?
It is located in the neck on the posterior and anterior surfaces of the trachea below the larynx (Patton & Thibodeau, 2018).

How calcitonin and parathyroid hormone act together to regulate the homeostasis of blood calcium concentration?
The interactions of calcitonin and parathyroid hormone are essential in bone remodeling. Calcitonin decreases serum calcium levels, while the parathyroid hormone increases serum calcium levels (Mader & Windelspecht, 2017)

Name some effects of Cortisol in the body.
Cortisol helps the body respond to stress, increase glucose metabolism, reduce inflammation and control blood sugar (Mader & Windelspecht, 2017)

Name two of the four principal hormones secreted by the pancreatic islets
Insulin

Glucagon (Patton & Thibodeau, 2018)

In what way do insulin and glucagon exert antagonistic influences on the concentration of glucose in the blood?
Insulin reduces blood sugar concentration, while glucagon increases blood sugar levels (Mader & Windelspecht, 2017). This results in optimum blood sugar levels.

What are the major hormones secreted by reproductive tissues (Gonads and placenta)?
Testes- testosterone, inhibin,

Ovaries- estrogen and progesterone

Placenta- Human chorionic gonadotropin (Patton & Thibodeau, 2018)

References
Mader, S., & Windelspecht, M. (2017). Human biology (15th ed.). McGraw-Hill Education.

Patton, K. T., & Thibodeau, G. A. (2018). Anthony’s Textbook of Anatomy and Physiology (21st ed.). Mosby.