Module 1

MSLP 540: Anatomy and Physiology of the Structures of Speech, Language and Hearing Mechanism

Module 1: Introduction to Human Anatomy and Physiology

A&P: Principles of Complementarities

• Anatomy:

  • Definition: The study of the structures and parts of multicellular organisms.

  • Origin: From Greek 'Ana' meaning up and 'tome' meaning cut.

• Physiology:

  • Definition: The study of the biological function of multicellular organisms.

  • Origin: From Greek 'Physis' meaning nature and 'logos' meaning study.

• Functional Human Anatomy:

  • Definition: The study of how the human body works, progressing from cells to tissues to organs to systems.

• **Principle of Complementarities: **

  • Definition: The function of a structure is closely related to its specific form.

  • Explanation: What a structure can do depends on its shape and arrangement.

Cells: Types

• Basic Units of Structure and Function:

  • Humans approximately have 100 trillion cells.

  • Cell Diversity:

  • Cells vary in function and structural adaptations based on their specific purposes.

  • Some cells are specialized for specific tasks:

    • Nerve Cells: Long projections facilitate electric messages between cells.

    • Muscle Cells (Mx): Equipped with many mitochondria to provide energy for muscle movement.

  • Commonality Among Cells:

  • Despite their diversity, all cells share similar metabolic requirements and structural components, including:

    • Organelles: nucleus, cytoplasm, membranes, etc.

  • Tissue Composition:

  • Each tissue consists of cells differentiated in morphology with specific functions.

  • Each organ contains at least two types of tissues.

Cells

• Definition: The smallest unit of life.

• Key Components of All Cells:

  • A nucleus (contains genetic material).

  • Cytoplasm.

  • Membrane.

• Differentiation:

  • Cells differ based on the type of tissue and are specialized for particular functions.

Tissues

• Four Types of Basic Tissue:

  1. Connective Tissue:

  • Definition: Cells that form the body's structure.

  • Examples: Bone, cartilage.

  1. Epithelial Tissue:

  • Definition: Cells that line inner and outer body surfaces; protect the body and its internal organs, secrete substances such as hormones, and absorb nutrients.

  • Examples: Skin, outer stomach lining.

  1. Muscle Tissue:

  • Definition: Cells that contract to enable movement.

  • Types:

    • Skeletal/Striated Muscle: Voluntary, controlled by the somatic nervous system; examples include the biceps.

    • Smooth Muscle: Involuntary, connected to the autonomic nervous system; examples include muscles in arteries and veins.

    • Cardiac Muscle: Involuntary, composed of interconnected cells; example includes the heart muscles.

  1. Nervous Tissue:

  • Definition: Composed of neurons that carry electrical messages between cells.

  • Function: Forms the brain, nerves connecting the brain to various body parts.

  • Examples: Vagus nerve, lower motor neurons.

Tissue: Connective Tissue

• Characteristics:

  • Composed of intracellular material (matrix).

  • Provides structural support and binds cells together.

  • Consistencies:

  • Solid

  • Liquid

  • Gel-like

  • Examples of Connective Tissue:

  • Skin, adipose tissue, bone.

• Bone:

  • Hardest of connective tissues due to a high content of inorganic salts.

  • Types of bone:

  • Compact bone (outer layer)

  • Spongy bone (interior, found inside the medullary cavity) containing bone marrow.

Tissue: Epithelial Tissue

• Function:

  • Forms external membranes.

  • Composed primarily of cells with minimal intracellular material.

  • Creates protective coatings such as skin, arterial linings and heart.

Muscle Tissue

• Description:

  • Comprised of fibers similar to bunched rubber bands.

  • Primary function: to contract.

• Types of Muscle Tissue:

  • Skeletal (Striated) Muscle:

  • Voluntary

  • Controlled by the somatic nervous system.

  • Example: Biceps.

  • Smooth Muscle:

  • Involuntary

  • Connected to the autonomic nervous system.

  • Example: Muscles in arteries and veins.

  • Cardiac Muscle:

  • Involuntary

  • Structure: cells interconnected as a mesh.

  • Example: Heart muscles.

Muscle Tissue: Innervation

• Innervation:

  • All muscles are innervated by the nervous system, which consists of nerves.

• **Types of Nerves: **

  • Afferent Nerves:

  • Carry sensory information from the body to the brain.

  • Efferent Nerves:

  • Transport motor information from the brain to the body, facilitating muscle movement.

• Muscle Classification:

  • Voluntary muscles can be classified into:

  • Agonist (primary movers)

  • Antagonist (opposing muscles).

Types of Muscle Fibers

• Different types of muscle fibers are utilized for various functions in the body, depending on their physiological needs and activities that they are involved in.

Nervous Tissue

• Nervous Tissue Composition:

  • Comprised solely of neurons; designed for communication between body parts, organs, and systems.

• Neurons Variability:

  • Vary in form and structure based on specific functions.

  • Information Transmission:

  • Interneuron: from one neuron to another.

  • Efferent: from the brain to muscles.

  • Afferent: from sensory terminals to the brain.

Other Important Structures

• Tendons:

  • Connect muscle to bone and can withstand tension, having some elasticity.

• Cartilage:

  • Tough structure providing support and protection; lacks blood and nerve supply.

  • Elastic.

• Ligaments:

  • Connect bone to bone; when overstretched, they struggle to retain their original shape and are non-elastic.

Organs

• Definition:

  • A group of at least two different tissues that form a distinct structure, performing a specific function.

• Organ Composition:

  • Various tissues combine to form organs such as the esophagus and heart.

  • Consists of body tissues working together for functional unity, sometimes comprising three or more different types of tissues.

Homeostasis: Maintaining and Failure

• Maintenance:

  • The process by which organ systems work to preserve a stable internal environment, requiring constant adjustments.

  • Example: Excretory system action when low levels of water trigger kidney retention of water, leading to more concentrated urine and less water loss from the body.

• Failure:

  • Continuous effort of homeostatic mechanisms can sometimes fail:

  • Cells may not receive necessary substrates for survival.

  • Toxic waste may accumulate in the body, leading to potential imbalances.

  • Prolonged failure to restore homeostasis may result in diseases or death.

Planes of Orientation: Terminology I

• Sagittal Plane:

  • Divides the body into right and left portions.

• Transverse Plane:

  • Divides the body into superior (upper) and inferior (lower) parts.

• Coronal, Frontal, or Anterior Plane:

  • Divides the body into anterior (front) and posterior (back) portions.

Planes of Orientation: Terminology II

• Directional Terms:

  • Anterior:

  • Towards the front of the body.

  • Posterior:

  • Towards the back of the body.

  • Lateral:

  • Related to the side of the body.

  • Contralateral:

  • Pertaining to the opposite side of the body.

  • Ipsilateral:

  • Pertaining to the same side of the body.

  • Bilateral:

  • Relating to both sides of the body.

Planes of Orientation: Terminology II (Cont. 1)

• Inferior (Infra):

  • Situated below or towards the ground.

• Superior (Supra):

  • Positioned above or further from the ground.

• Distal:

  • Located away from the midline of the body.

• Proximal:

  • Closest to the point of attachment; nearer to the trunk.

Planes of Orientation: Terminology II (Cont. 2)

• Lateral:

  • Towards the side of the body.

• Medial:

  • Toward the midline of the body.

• Deep:

  • Further away from the surface, often used to describe muscles and tissues' location.

• Superficial:

  • Near the surface, describing muscles and tissues' location.

Planes of Orientation: Terminology II (Cont. 3)

• Abduction:

  • Movement away from the midline of the body.

• Adduction:

  • Movement toward the midline of the body.