Endocrine, Cardiovascular, and Nervous Systems: Study Guide for Anatomy & Physiology

Endocrine System

Overview of Endocrine Glands and Hormones

The endocrine system consists of glands that secrete hormones directly into the bloodstream to regulate various body functions. Each gland produces specific hormones that target organs and tissues.

• Pineal Gland

  • Hormone: Melatonin

  • Function: Regulates sleep-wake cycles and circadian rhythms.

• Hypothalamus

  • Hormones: ACTH, LH, FSH, TSH, GH, PRL

  • Function: Controls pituitary gland; regulates homeostasis, hunger, thirst, and other autonomic functions.

• Posterior Pituitary Gland

  • Hormones: Oxytocin, Antidiuretic Hormone (ADH)

  • Function: Oxytocin stimulates uterine contractions and milk ejection; ADH regulates water balance.

• Anterior Pituitary Gland

  • Hormones: Growth Hormone (GH), Prolactin (PRL), Thyroid-Stimulating Hormone (TSH), Adrenocorticotropic Hormone (ACTH), Luteinizing Hormone (LH), Follicle-Stimulating Hormone (FSH)

  • Function: Regulates growth, metabolism, reproduction, and lactation.

• Thyroid Gland

  • Hormones: T3, T4, Calcitonin

  • Function: Controls metabolism and calcium levels.

• Parathyroid Glands

  • Hormone: Parathyroid Hormone (PTH)

  • Function: Regulates calcium levels in the blood.

• Adrenal Glands

  • Hormones: Cortisol, Aldosterone, Epinephrine, Norepinephrine

  • Function: Regulates stress response, metabolism, and electrolyte balance.

• Kidneys

  • Hormone: ADH

  • Function: Regulates water balance and blood pressure.

• Digestive Tract

  • Hormone: Gastrin

  • Function: Stimulates gastric acid secretion.

• Pancreas

  • Hormones: Insulin, Glucagon

  • Function: Regulates blood glucose levels.

• Ovaries and Testes

  • Hormones: Estrogen, Progesterone, Testosterone

  • Function: Regulate reproductive functions and secondary sex characteristics.

Key Terms and Concepts

• Hormone: Chemical messenger secreted by glands.

• Target Organ: Organ or tissue affected by a specific hormone.

• Negative Feedback: Mechanism that maintains homeostasis by inhibiting hormone production when levels are sufficient.

Cardiovascular System

Blood and Blood Cells

The cardiovascular system transports nutrients, gases, hormones, and waste products throughout the body. Blood consists of plasma and formed elements (cells).

• Red Blood Cells (RBCs): Carry oxygen via hemoglobin; biconcave shape increases surface area for gas exchange.

• White Blood Cells (WBCs): Defend against infection; several types including neutrophils, lymphocytes, monocytes, eosinophils, and basophils.

• Platelets: Cell fragments involved in blood clotting.

Blood Types

• ABO System: Classification based on presence of antigens A and B on RBCs.

• Rh Factor: Presence (+) or absence (−) of Rh antigen.

Blood Vessels

Blood vessels form a closed circuit to transport blood throughout the body. There are three main types:

• Arteries: Carry blood away from the heart; thick muscular walls.

• Veins: Carry blood toward the heart; thinner walls, often have valves.

• Capillaries: Microscopic vessels for exchange of gases, nutrients, and waste.

Arterial System

• Brachiocephalic trunk

• Left common carotid

• Left subclavian

• Ascending aorta

• Aortic arch

• Descending aorta

• Renal arteries

• Femoral arteries

• Popliteal arteries

• Radial and ulnar arteries

Venous System

• Jugular veins (internal and external)

• Subclavian veins

• Femoral veins

• Great saphenous vein

Types of Circulation

• Systemic Circulation: Delivers oxygenated blood to tissues and returns deoxygenated blood to the heart.

• Pulmonary Circulation: Carries deoxygenated blood to the lungs for oxygenation.

Heart Function and Electrical Activity

• P Wave: Atrial depolarization

• QRS Complex: Ventricular depolarization

• T Wave: Ventricular repolarization

Nervous System

Central and Peripheral Nervous Systems

The nervous system is divided into the central nervous system (CNS) and peripheral nervous system (PNS). The CNS includes the brain and spinal cord; the PNS includes all neural tissue outside the CNS.

• Ascending Tracts: Carry sensory information to the brain.

• Descending Tracts: Carry motor commands from the brain to muscles.

• Spinal Cord: Transmits signals between brain and body; contains gray and white matter.

Major Brain Regions and Functions

• Cerebrum: Higher cognitive functions, voluntary movement, sensory perception.

• Cerebellum: Coordination and balance.

• Brainstem: Controls vital functions (breathing, heart rate).

• Thalamus: Relay center for sensory information.

• Hypothalamus: Regulates autonomic functions and links nervous and endocrine systems.

Neurons and Neuroglia

• Neuron: Functional unit of the nervous system; transmits electrical impulses.

• Neuroglia: Support and protect neurons.

Reflex Arcs and Pathways

• Reflex Arc: Pathway involving sensory neuron, interneuron, and motor neuron for rapid response.

• Somatic Reflexes: Involve skeletal muscles.

• Autonomic Reflexes: Involve smooth muscle, cardiac muscle, or glands.

Key Terms

• Gray Matter: Contains neuron cell bodies.

• White Matter: Contains myelinated axons.

• Ganglia: Clusters of neuron cell bodies in the PNS.

Tables

Major Endocrine Glands and Their Hormones

Gland	Hormone(s)	Main Function
Pineal	Melatonin	Regulates circadian rhythms
Thyroid	T3, T4, Calcitonin	Metabolism, calcium regulation
Parathyroid	PTH	Raises blood calcium
Adrenal	Cortisol, Aldosterone, Epinephrine	Stress response, metabolism
Pancreas	Insulin, Glucagon	Regulates blood glucose
Ovaries/Testes	Estrogen, Progesterone, Testosterone	Reproduction

Types of Blood Cells

Cell Type	Main Function
Red Blood Cell (Erythrocyte)	Oxygen transport
White Blood Cell (Leukocyte)	Immune defense
Platelet (Thrombocyte)	Blood clotting

Key Equations

• Blood Pressure: $\text{Blood Pressure} = \text{Cardiac Output} \times \text{Peripheral Resistance}$

• Cardiac Output: $\text{Cardiac Output} = \text{Stroke Volume} \times \text{Heart Rate}$

Additional info:

• Some content inferred and expanded for completeness, including definitions and functions of hormones, blood cells, and nervous system structures.

• Tables reconstructed for clarity and study purposes.