Brain Hormones, Cell Communication, and Skeletal System Review

These flashcards cover key concepts related to brain hormones, cell communication, endocrine system, skeletal structure, and related physiological processes

How do neurons connected with an electric synapse communicate?

Through ions flowing through gap junctions.

What is the role of platelet-derived growth factor (PDGF) in wound healing?

PDGF, secreted by activated platelets, activates adjacent fibroblasts to proliferate and produce collagen.

What is the hypothalamic-pituitary-thyroid (HPT) axis?

A neuroendocrine system that regulates metabolism through sequential regulation of TRH, TSH, and thyroid hormones.

What are the effects of high levels of thyroid hormone?

Weight loss, increased heart rate, nervousness & anxiety, and sweating

What is the function of calcitonin?

Lowers blood calcium by preventing the breakdown of bone.

What is the main function of parathyroid hormone?

Increases blood calcium by stimulating calcium release from the bone.

How does Vitamin D affect calcium levels?

Promotes calcium absorption from the intestine and the kidney, increasing blood calcium.

What is the effect of long-term high cortisol on the immune system?

Suppresses the immune system, especially B and T cells.

What are some symptoms of Cushing's syndrome?

Weight gain, thin limbs, and muscle waste, caused by prolonged high cortisol.

What is the major function of DHEA and DHEAS?

Serve as precursors for sex hormone synthesis, contributing to the development of secondary sexual characteristics and increasing libido.

What are the primary functions of the thyroid hormone?

Increase basal metabolic rate and also increase the rate of anabolism, especially promoting protein synthesis.

What is the role of red bone marrow?

Vital tissue that is the only place to generate new blood cells in adults.

How does calcitriol influence calcium levels in the body?

Increases calcium both in the blood and in the bone by increasing calcium absorption from food.

What is the main function of aldosterone?

To stimulate Na+ absorption in the kidney and thus increase water retention within the blood, leading to increased blood pressure.

What hormone induces various stress responses in different tissues?

Cortisol

What is the function of the exocrine pancreas?

Acinar cells produce digestive enzymes, and ductal cells transfer enzymes and produce bicarbonate to neutralize gastric acid.

What is the function of insulin?

Reduces blood glucose levels by promoting glucose uptake in muscle and fat cells and regulating glucose metabolism in liver hepatocytes.

How is insulin release regulated?

By elevated blood glucose levels, which directly stimulate β cells to release insulin.

How does glucagon affect blood glucose levels?

Elevates the blood glucose level mainly by stimulating the liver to break glycogen and release glucose (glycogenolysis).

What is the function of somatostatin in the pancreas?

Inhibits the action of both α and β cells, thus inhibiting both glucagon and insulin.

What are Incretins?

GIP (glucose-dependent insulinotropic polypeptide) and GLP-1 (glucagon-like peptide 1) are 2 major types of incretins, which increase insulin secretion in a glucose-dependent manner.

How does GLP-1 affect insulin secretion?

GLP-1 increases insulin secretion in a glucose-dependent manner.

What is the role of the supportive system?

Includes the skeletal system, muscular system, and, in some species, integumentary system, which work together to provide structural support to the body.

What are the two vasculatures in vascular plants?

Phloem (transports molecules from green top down) and Xylem (transports water and minerals from roots up).

What is the function of the notochord?

A flexible rod-like structure that is critically important for human embryonic development.

When does the notochord develop?

The notochord develops in the human embryo on day 16.

What signaling molecule does the notochord produce?

Shh (sonic hedgehog).

How does the jaw evolve?

Evolved from a gill opening.

What are the components of cartilage matrix?

Collagen and proteoglycan

What are the types of cartilage tissue?

Hyaline, Fibrocartilage, and Elastic

What are the categories of bones according to shape?

Irregular | Long | Short | Flat | Sesamoid

The process of bone formation is called?

Ossification

What fish evolved into tetrapods?

Lobe-finned Fish

What are the two most common forms of ossification?

Endocondral and Intramembranous