Skip to main content

Fundamentals of Anatomy and Physiology: 6.5 Development of the Heart

Fundamentals of Anatomy and Physiology
6.5 Development of the Heart
    • Notifications
    • Privacy
  • Project HomeNatural Sciences Collection: Anatomy, Biology, and Chemistry
  • Projects
  • Learn more about Manifold

Notes

Show the following:

  • Annotations
  • Resources
Search within:

Adjust appearance:

  • font
    Font style
  • color scheme
  • Margins
table of contents
  1. Cover
  2. Title Page
  3. Copyright
  4. Table Of Contents
  5. About the Authors
  6. Acknowledgments
  7. Preface
  8. Levels of Organisation, Homeostasis and Nomenclature
    1. 1.1 Overview of Anatomy and Physiology
    2. 1.2 Structural Organisation of the Human Body
    3. 1.3 Homeostasis
    4. 1.4 Anatomical Terminology
  9. Cells and Reproduction
    1. 2.1 Synthesis of Biological Macromolecules
    2. 2.2 Carbohydrates
    3. 2.3 Lipids
    4. 2.4 Protein
    5. 2.5 Nucleic Acid
    6. 2.6 The Cell Membrane
    7. 2.7 The Cytoplasm and Cellular Organelles
    8. 2.8 The Nucleus and DNA Replication
    9. 2.9 Protein Synthesis
    10. 2.10 Cell Growth and Division
    11. 2.11 Cellular Differentiation
  10. Tissues, Organs, Systems
    1. 3.1 Types of Tissues
    2. 3.2 Epithelial Tissue
    3. 3.3 Connective Tissue Supports and Protects
    4. 3.4 Muscle Tissue and Motion
    5. 3.5 Nervous Tissue Mediates Perception and Response
    6. 3.6 Tissue Injury and Ageing
  11. Integumentary System
    1. 4.1 Layers of the Skin
    2. 4.2 Accessory Structures of the Skin
    3. 4.3 Functions of the Integumentary System
    4. 4.4 Diseases, Disorders and Injuries of the Integumentary System
  12. Blood
    1. 5.1 An Overview of Blood
    2. 5.2 Production of the Formed Elements
    3. 5.3 Erythrocytes
    4. 5.4 Leukocytes and Platelets
    5. 5.5 Haemostasis
    6. 5.6 Blood Typing
  13. Cardiovascular System
    1. 6.1 Heart Anatomy
    2. 6.2 Cardiac Muscle and Electrical Activity
    3. 6.3 Cardiac Cycle
    4. 6.4 Cardiac Physiology
    5. 6.5 Development of the Heart
    6. 6.6 Structure and Function of Blood Vessels
    7. 6.7 Blood Flow, Blood Pressure and Resistance
    8. 6.8 Capillary Exchange
    9. 6.9 Homeostatic Regulation of the Vascular System
    10. 6.10 Circulatory Pathways
    11. 6.11 Development of Blood Vessels and Foetal Circulation
  14. Lymphatic System and Immunity
    1. 7.1 Anatomy of the Lymphatic and Immune Systems
    2. 7.2 Barrier Defences and the Innate Immune Response
    3. 7.3 The Adaptive Immune Response: T Lymphocytes and their Functional Types
    4. 7.4 The Adaptive Immune Response: B-Lymhocytes and Antibodies
    5. 7.5 The Immune Response Against Pathogens
    6. 7.6 Diseases Associated with Depressed or Overactive Immune Responses
    7. 7.7 Transplantation and Cancer Immunology
  15. Respiratory System
    1. 8.1 Organs and Structures of the Respiratory System
    2. 8.2 The Lungs
    3. 8.3 The Process of Breathing
    4. 8.4 Gas Exchange
    5. 8.5 Transport of Gases
    6. 8.6 Modifications in Respiratory Functions
    7. 8.7 Embryonic Development of the Respiratory System
  16. Muscle System
    1. 9.1 Overview of Muscle Tissues
    2. 9.2 Skeletal Muscle
    3. 9.3 Muscle Fibre Contraction and Relaxation
    4. 9.4 Nervous System Control of Muscle Tension
    5. 9.5 Types of Muscle Fibres
    6. 9.6 Exercise and Muscle Performance
    7. 9.7 Cardiac Muscle Tissue
    8. 9.8 Smooth Muscle
    9. 9.9 Development and Regeneration of Muscle Tissue
  17. Skeletal System
    1. 10.1 The Functions of the Skeletal System
    2. 10.2 Bone Classification
    3. 10.3 Bone Structure
    4. 10.4 Bone Formation and Development
    5. 10.5 Fractures: Bone Repair
    6. 10.6 Exercise, Nutrition, Hormones and Bone Tissue
    7. 10.7 Calcium Homeostasis: Interactions of the Skeletal System and Other Organ Systems
    8. 10.8 Divisions of the Skeletal System
    9. 10.9 The Skull
    10. 10.10 The Vertebral Column
    11. 10.11 The Thoracic Cage
    12. 10.12 Embryonic Development of the Axial Skeleton
  18. Musculoskeletal System
    1. 11.1 The Pectoral Girdle
    2. 11.2 Bones of the Upper Limb
    3. 11.3 The Pelvic Girdle and Pelvis
    4. 11.4 Bones of the Lower Limb
    5. 11.5 Development of the Appendicular Skeleton
    6. 11.6 Classification of Joints
    7. 11.7 Fibrous Joints
    8. 11.8 Cartilaginous Joints
    9. 11.9 Synovial Joints
    10. 11.10 Types of Body Movements
    11. 11.11 Anatomy of Selected Synovial Joints
    12. 11.12 Development of Joints
  19. Digestive System
    1. 12.1 Overview of the Digestive System
    2. 12.2 Digestive System Processes and Regulation
    3. 12.3 The Mouth, Pharynx and Oesophagus
    4. 12.4 The Stomach
    5. 12.5 The Small and Large Intestines
    6. 12.6 Accessory Organs in Digestion: the Liver, Pancreas and Gallbladder
    7. 12.7 Chemical Digestion and Absorption
  20. Nervous System
    1. 13.1 Basic Structure and Function of the Nervous System
    2. 13.2 Nervous Tissue
    3. 13.3 The Function of Nervous Tissue
    4. 13.4 The Action Potential
    5. 13.5 Communication between Neurons
    6. 13.6 The Embyrologic Perspective
    7. 13.7 The Central Nervous System
    8. 13.8 Circulation and the Central Nervous System
    9. 13.9 The Peripheral Nervous System
    10. 13.10 Sensory Perception
    11. 13.11 Central Processing
    12. 13.12 Motor Responses
  21. Endocrine System
    1. 14.1 An Overview of the Endocrine System
    2. 14.2 Hormones
    3. 14.3 The Pituitary Gland and Hypothalamus
    4. 14.4 The Thyroid Gland
    5. 14.5 The Parathyroid Glands
    6. 14.6 The Adrenal Glands
    7. 14.7 The Pineal Gland
    8. 14.8 Gonadal and Placental Hormones
    9. 14.9 The Endocrine Pancreas
    10. 14.10 Organs with Secondary Endocrine Functions
    11. 14.11 Development and Ageing of the Endocrine System
  22. Reproductive System
    1. 15.1 Anatomy and Physiology of the Male Reproductive System
    2. 15.2 Anatomy and Physiology of the Female Reproductive System
    3. 15.3 Development of the Male and Female Reproductive Systems
  23. Pregnancy and Human Development
    1. 16.1 Fertilisation
    2. 16.2 Embryonic Development
    3. 16.3 Foetal Development
  24. Urinary System
    1. 17.1 Physical Characteristics of Urine
    2. 17.2 Gross Anatomy of Urine Transport
    3. 17.3 Gross Anatomy of the Kidney
    4. 17.4 Microscopic Anatomy of the Kidney
    5. 17.5 Physiology of Urine Formation
    6. 17.6 Tubular Reabsorption
    7. 17.7 Regulation of Renal Blood Flow
    8. 17.8 Endocrine Regulation of Kidney Function
    9. 17.9 Regulation of Fluid Volume and Composition
    10. 17.10 The Urinary System and Homeostasis
    11. 17.11 Body Fluids and Fluid Compartments
    12. 17.12 Water Balance
    13. 17.13 Electrolyte Balance
    14. 17.14 Acid-Base Balance
    15. 17.15 Disorders of Acid-Base Balance
  25. Appendix A: Unit Measurements and Calculations
  26. Appendix B: Chemical Abbreviations
  27. Glossary
  28. Bibliography

6.5 Development of the Heart

Learning Objectives

By the end of this section, you will be able to:

  • Describe the embryological development of heart structures
  • Identify five regions of the foetal heart
  • Relate foetal heart structures to adult counterparts

The human heart is the first functional organ to develop. It begins beating and pumping blood around day 21 or 22, a mere three weeks after fertilisation. This emphasises the critical nature of the heart in distributing blood through the vessels and the vital exchange of nutrients, oxygen, and wastes both to and from the developing baby. The critical early development of the heart is reflected by the prominent heart bulge that appears on the anterior surface of the embryo.

The heart forms from an embryonic tissue called mesoderm around 18 to 19 days after fertilisation. Mesoderm is one of the three primary germ layers that differentiates early in development that collectively gives rise to all subsequent tissues and organs. The heart begins to develop near the head of the embryo in a region known as the cardiogenic area. Following chemical signals called factors from the underlying endoderm (another of the three primary germ layers), the cardiogenic area begins to form two strands called the cardiogenic cords (Figure 6.5.1). As the cardiogenic cords develop, a lumen rapidly develops within them. At this point, they are referred to as endocardial tubes. The two tubes migrate together and fuse to form a single primitive heart tube. The primitive heart tube quickly forms five distinct regions. From head to tail, these include the truncus arteriosus, bulbus cordis, primitive ventricle, primitive atrium, and the sinus venosus. Initially, all venous blood flows into the sinus venosus, and contractions propel the blood from tail to head, or from the sinus venosus to the truncus arteriosus. This is a very different pattern from that of an adult.

This diagram outlines the embryological development of the human heart during the first eight weeks and the subsequent formation of the four heart chambers.
Figure 6.5.1. Development of the human heart. This diagram outlines the embryological development of the human heart during the first eight weeks and the subsequent formation of the four heart chambers.

The five regions of the primitive heart tube develop into recognisable structures in a fully developed heart. The truncus arteriosus will eventually divide and give rise to the ascending aorta and pulmonary trunk. The bulbus cordis develops into the right ventricle. The primitive ventricle forms the left ventricle. The primitive atrium becomes the anterior portions of both the right and left atria, and the two auricles. The sinus venosus develops into the posterior portion of the right atrium, the SA node, and the coronary sinus.

As the primitive heart tube elongates, it begins to fold within the pericardium, eventually forming an S shape, which places the chambers and major vessels into an alignment like the adult heart. This process occurs between days 23 and 28. The remainder of the heart development pattern includes development of septa and valves and remodelling of the actual chambers. Partitioning of the atria and ventricles by the interatrial septum, interventricular septum, and atrioventricular septum is complete by the end of the fifth week, although the foetal blood shunts remain until birth or shortly after. The atrioventricular valves form between weeks five and eight, and the semilunar valves form between weeks five and nine.

Section Review

The heart is the first organ to form and become functional, emphasising the importance of transport of material to and from the developing infant. It originates about day 18 or 19 from the mesoderm and begins beating and pumping blood about day 21 or 22. It forms from the cardiogenic region near the head and is visible as a prominent heart bulge on the surface of the embryo. Originally, it consists of a pair of strands called cardiogenic cords that quickly form a hollow lumen and are referred to as endocardial tubes. These then fuse into a single heart tube and differentiate into the truncus arteriosus, bulbus cordis, primitive ventricle, primitive atrium, and sinus venosus, starting about day 22. The primitive heart begins to form an S shape within the pericardium between days 23 and 28. The internal septa begin to form about day 28, separating the heart into the atria and ventricles, although the foramen ovale persists until shortly after birth. Between weeks five and eight, the atrioventricular valves form. The semilunar valves form between weeks five and nine.

Review Questions

An interactive H5P element has been excluded from this version of the text. You can view it online here:
https://usq.pressbooks.pub/anatomy/?p=514#h5p-123

Critical Thinking Questions

An interactive H5P element has been excluded from this version of the text. You can view it online here:
https://usq.pressbooks.pub/anatomy/?p=514#h5p-124

An interactive H5P element has been excluded from this version of the text. You can view it online here:
https://usq.pressbooks.pub/anatomy/?p=514#h5p-125

Click the drop down below to review the terms learned from this chapter.

An interactive H5P element has been excluded from this version of the text. You can view it online here:
https://usq.pressbooks.pub/anatomy/?p=514#h5p-126

Annotate

Next Chapter
6.6 Structure and Function of Blood Vessels
PreviousNext
Anatomy and Physiology
Copyright © 2021 by University of Southern Queensland Fundamentals of Anatomy and Physiology by University of Southern Queensland is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License, except where otherwise noted.
Powered by Manifold Scholarship. Learn more at
Opens in new tab or windowmanifoldapp.org