L5 - Endocrine system

• What is the study of hormones and glands called?

  Endocrinology
• Which gland is located behind the thyroid glands?

  Parathyroid glands
• What is the primary function of hormones?

  Regulate activities of cells or organs
• How do hormones reach their target tissues?

  They are carried by the circulatory system
• What is the effect of hormones on their target tissues?

  They exert effects at extremely low concentrations
• What are the similarities between the endocrine and nervous systems?

  Both maintain homeostasis using chemical messengers
• What are the differences between the endocrine and nervous systems?

  Endocrine uses circulatory system; nervous uses neurons
• What are the types of endocrine glands?

  • Adrenal glands
  • Pancreas
  • Ovaries
  • Testes
  • Pituitary gland
  • Pineal gland
  • Parathyroid glands
  • Thyroid gland
• How do endocrine glands release hormones?

  Through diffusion into vascular or lymphatic systems
• What are classic glandular hormones?

  Hormones released by endocrine glands into bloodstream
• What are neurohormones?

  Hormones produced from modified neurons
• What is the difference between autocrine and paracrine signaling?

  Autocrine acts on the same cell; paracrine acts locally
• What are the classifications of hormones based on their building blocks?

  Peptides, biogenic amines, steroids, eicosanoids
• How are peptide hormones synthesized?

  Using protein synthesis machinery in ribosomes
• What are biogenic amines derived from?

  Amino acids
• What are steroids synthesized from?

  Cholesterol
• What is the role of eicosanoids?

  Modulate inflammation and immune regulation
• How do hormones bind to their receptors?

  Highly specific binding to protein receptors
• What is the effect of water-soluble hormones?

  They act rapidly with shorter-lasting effects
• How do lipid-soluble hormones act?

  They bind to intracellular receptors and influence gene expression
• What regulates hormone levels in the body?

  Humoral, neural, and hormonal stimuli
• What is positive feedback in hormonal control?

  Stimulatory effect on hormone secretion
• What is negative feedback in hormonal control?

  Inhibitory effect to maintain constant hormone levels
• How do hormones interact to elicit their actions?

  Through additive, synergistic, or permissive effects
• What is the role of transport proteins in hormone movement?

  Facilitate movement of lipid-soluble hormones in blood
• What is the difference between feedforward and feedback systems?

  Feedforward anticipates changes; feedback responds to changes
• What is the role of thyroid hormones in reproductive system maturation?

  They are required for gonadotropin effects
• True or false: The endocrine system has a quicker onset than the nervous system.

  False
• True or false: Peptide hormones are synthesized using protein synthetic machinery.

  True
• True or false: Catecholamines are derived from cholesterol.

  False
• True or false: Cortisol is a steroid hormone that acts on G protein-coupled receptors.

  False
• True or false: Lipid-soluble hormones act on intracellular receptors.

  True
• True or false: Transport proteins facilitate movement of hormones in blood.

  True
• True or false: Feedforward systems respond to changes in hormone levels.

  False
• True or false: Negative feedback systems are stimulatory.

  False
• True or false: The presence of thyroid hormone is required for maturation of the reproductive system.

  True