JSCC ENDO

Nervous system vs Endocrine system

The nervous system uses electrical signals for fast communication, while the endocrine system uses hormones for slower, longer-lasting effects.

Homeostasis

Homeostasis is the maintenance of a stable internal environment in the body.

Endocrine gland vs Exocrine gland

Endocrine glands secrete hormones directly into the bloodstream, while exocrine glands secrete substances through ducts.

Pituitary gland location

located at the base of the brain.

Neurohypophysis

the posterior part of the pituitary gland.

Adenohypophysis

is the anterior part of the pituitary gland.

Infundibulum

the stalk that connects the pituitary gland to the hypothalamus.

Secretions of neurohypophysis

oxytocin and antidiuretic hormone (ADH).

Hypothalamus relationship with anterior pituitary

releases hormones that control the release of hormones from the anterior pituitary.

Thyroid gland follicular cells hormones

Thyroid hormones (T3 and T4) targeting various body tissues.

Thyroid gland parafollicular cells hormones

Calcitonin targeting bone cells.

Thymus gland hormones

Thymosin targeting T-cells in the immune system.

Adrenal medulla hormones

Epinephrine and norepinephrine targeting multiple organs during stress.

Adrenal cortex hormones

Cortisol and aldosterone targeting various tissues.

Pancreas hormones

Insulin and glucagon targeting the liver and muscle cells.

Anterior pituitary hormones

Growth hormone, prolactin, and others targeting different tissues.

Parathyroid gland hormones

Parathyroid hormone targeting bones and kidneys.

Posterior pituitary hormones

ADH and oxytocin targeting kidneys and reproductive organs.

Hypothalamus hormones

Releasing and inhibiting hormones that control the anterior pituitary.

Testes hormones

Testosterone targeting male reproductive tissues.

Ovaries hormones – follicles

Estrogen targeting female reproductive tissues.

Ovaries hormones – corpus luteum

Progesterone targeting the uterus.

leydig cells

Cells in the testes that produce testosterone; influence male secondary sexual characteristics and reproductive functions.

Insulin and glucagon relationship

Insulin decreases blood glucose levels, while glucagon increases them.

Steroid hormones

Examples include testosterone, estrogen, and cortisol all produced by adrenal cortex and gonads.

steroid hormones

derived from cholesterol

Cholesterol importance in hormones

Cholesterol is essential for the synthesis of steroid hormones.

What Happens When a Steroid Hormone Arrives at a Target Cell?

The steroid hormone passes through the cell membrane and binds to specific receptors in the cytoplasm or nucleus, initiating gene expression and protein synthesis.

Calorigenic effect of T3

The calorigenic effect refers to the increase in metabolic rate and heat production.

Glucose-sparing effect

Hormones like cortisol and epinephrine promote utilization of fats instead of glucose.

Difference between amplification and up-regulation

Amplification refers to the increase in hormone-receptor signaling, while up-regulation refers to an increase in the number of receptors.

Secondary messenger

Cyclic AMP (cAMP) involved in hormone signaling.

Micronutrient in thyroxine synthesis

Iodine is critical in the synthesis of thyroxine (T4).

Free hormone vs Bound hormone

Free hormones circulate unattached, while bound hormones are attached to plasma proteins.

Specificity of hormone function

The specificity of hormone action depends on the presence of specific receptors on target cells.

Grave’s Disease symptoms

Hyperthyroidism, weight loss, and anxiety caused by overactive thyroid glands.

Hashimoto’s Disease symptoms

Hypothyroidism, fatigue, and weight gain due to autoimmune destruction of thyroid tissue.

Diabetes Mellitus symptoms

High blood sugar levels leading to excessive thirst and urination due to insulin issues.

Hemostasis events

Includes vascular spasm, platelet plug formation, and blood coagulation.

Primary vs Secondary polycythemia

Primary is due to increased red blood cell production; secondary results from environmental conditions like oxygen deprivation.

Intrinsic factor importance

Essential for vitamin B12 absorption, crucial for red blood cell formation.

Bilirubin and biliverdin

Bilirubin is a breakdown product of hemoglobin; biliverdin is its precursor.

Spleen role in RBC processing

The spleen filters and removes old red blood cells from circulation.

Phagocytic leukocytes

Neutrophils and monocytes are key phagocytic white blood cells.

Platelet formation location

Platelets are formed in the bone marrow.

Hemolytic disease of the newborn

A condition caused by blood type incompatibility, treated with Rho(D) immune globulin.

Universal donor blood type

O- is the universal donor due to lack of antigens.

Antibodies in type O and AB individuals

Type O has anti-A and anti-B; type AB has none, making them universal recipients.