Chemistry

Basic Chemical Principles in Physiology

Chemistry forms the foundation for understanding physiological processes in the human body. Key chemical concepts are essential for grasping how cells and systems function.

• Charge of Sub-atomic Particles: Protons (positive), neutrons (neutral), and electrons (negative) are the main subatomic particles. Their arrangement determines atomic structure and reactivity.

• Ionic Bonds: Formed when electrons are transferred from one atom to another, resulting in oppositely charged ions that attract each other. Example: NaCl (table salt).

• Covalent Bonds: Formed when two atoms share one or more pairs of electrons. Example: H2O (water).

Example: The stability of biological molecules like DNA and proteins depends on covalent and ionic bonds.

Endocrine System

Hormonal Regulation and Glandular Function

The endocrine system uses hormones to regulate body processes. Understanding hormone synthesis, release, and action is crucial for physiology.

• Hypothalamic-Hypophyseal Portal System: A network of blood vessels connecting the hypothalamus and anterior pituitary, allowing for direct hormone transport.

• Purpose of Adrenal Cortex: Produces steroid hormones such as cortisol and aldosterone, which regulate metabolism and electrolyte balance.

• Synthesis of Hormones: Hormones are synthesized in endocrine glands from amino acids or cholesterol.

• Why Iodine is Essential to Hormone Function: Iodine is required for the synthesis of thyroid hormones (T3 and T4).

• Steroid Hormone Characteristics: Lipid-soluble, pass through cell membranes, bind to intracellular receptors, and regulate gene expression.

• Glucagon and Insulin Relationship: Glucagon raises blood glucose; insulin lowers it. They work antagonistically to maintain glucose homeostasis.

• Hormone Response to Blood Glucose: High blood glucose stimulates insulin release; low blood glucose stimulates glucagon release.

• What Happens When Your Core Body Temperature Decreases? The hypothalamus triggers mechanisms such as shivering and vasoconstriction to conserve heat.

• Positive Feedback Loop: A process where the end product enhances the original stimulus. Example: Oxytocin release during childbirth.

Homeostasis

Maintaining Internal Balance

Homeostasis is the process by which the body maintains a stable internal environment despite external changes.

• Definition: The maintenance of a constant internal environment within physiological limits.

• Example: Regulation of body temperature, pH, and blood glucose levels.

Bone

Structure and Function of Bone Tissue

Bones provide support, protection, and facilitate movement. They also play a role in mineral storage and blood cell production.

• Ossification: The process of bone formation from cartilage or fibrous tissue.

• Purpose of Parathyroid Gland: Regulates calcium levels in the blood by releasing parathyroid hormone (PTH).

• What Characteristic of Bone Allows the Tissue to be Resistant to Shattering? The combination of collagen fibers (flexibility) and mineral salts (hardness).

• Canaliculi: Small channels in bone that allow for nutrient and waste exchange between osteocytes.

• Synovial Joints Examples: Knee, elbow, shoulder, and hip joints.

• Gomphosis: A type of fibrous joint where a peg fits into a socket, such as teeth in the jawbone.

• Long Bone Marking Characteristics: Include features such as the diaphysis (shaft), epiphyses (ends), and various projections for muscle attachment.

• Location of Red Bone Marrow: Found in the spongy bone of flat bones and the ends of long bones; site of hematopoiesis.

• Fibrocartilage: A tough, dense type of cartilage found in intervertebral discs and pubic symphysis.

• Ligament: Connects bone to bone, providing joint stability.

• Location of Meatues: Meatus refers to a canal-like passageway in bone, such as the external auditory meatus in the skull.

• Fibrocartilage: (Repeated) See above.

Muscle

Muscle Tissue Types and Properties

Muscle tissue is specialized for contraction and movement. There are three types: skeletal, cardiac, and smooth muscle.

• Purpose of Adductors: Muscles that move a limb toward the body's midline.

• Four Properties of All Muscle Tissues:

  1. Excitability (responsiveness to stimuli)

  2. Contractility (ability to shorten)

  3. Extensibility (ability to stretch)

  4. Elasticity (ability to return to original shape)

• Function of Troponin: Regulatory protein in muscle contraction; binds calcium to allow actin-myosin interaction.

• Slow Twitch Fibers: Muscle fibers adapted for endurance and continuous contraction; rich in mitochondria and myoglobin.

• Location of Sarcolemma: The plasma membrane of a muscle fiber.

• Latent Period: The brief delay between stimulus and muscle contraction.

• Amphiarthrosis Joints: Slightly movable joints, such as the intervertebral discs.

• Action of Gastrocnemius and Soleus Muscles: Both muscles are involved in plantar flexion of the foot at the ankle.

Nervous System

Neural Control and Integration

The nervous system coordinates body activities through electrical and chemical signals.

• Complete Tetany: A sustained muscle contraction without relaxation.

• Purpose of Receptors: Detect changes in the environment and initiate nerve impulses.

• Parasympathetic Nervous System: Part of the autonomic nervous system; promotes 'rest and digest' activities.

• Function of Medulla Oblongata: Controls vital autonomic functions such as heart rate and respiration.

• Typical Reflex Arc: The pathway followed by nerve impulses during a reflex action, usually involving a sensory neuron, interneuron, and motor neuron.

Tissues

Types and Functions of Body Tissues

Tissues are groups of similar cells that perform specific functions. There are four basic types: epithelial, connective, muscle, and nervous tissue.

• Difference Between Epithelial Tissues and Connective Tissues: Epithelial tissues cover surfaces and line cavities; connective tissues support, bind, and protect organs.

• Specialized Connective Tissues: Include bone, cartilage, blood, and lymph.

• Characteristics of Simple Cuboidal Epithelium: Single layer of cube-shaped cells; functions in secretion and absorption.

• Mesothelium: The simple squamous epithelium lining body cavities.

• Fibroblast: A cell that produces collagen and other fibers in connective tissue.

• Perichondrium: Dense layer of connective tissue surrounding cartilage.

Organ Systems

• Which Systems Transport Throughout the Body? The circulatory and lymphatic systems are primarily responsible for transport of substances.

Cells

Cellular Organization and Recycling

Cells are the basic structural and functional units of life.

• Cellular Organelles Used to Recycle Materials: Lysosomes contain digestive enzymes to break down waste and cellular debris.

Integumentary System

Skin Structure and Function

The integumentary system includes the skin, hair, nails, and associated glands. It protects the body and helps regulate temperature.

• Protein Keratin: A tough, fibrous protein that provides strength and waterproofing to the skin, hair, and nails.

• Dermis Elements: Contains connective tissue, blood vessels, nerve endings, and glands.

• Function of Arrector Pili Muscles: Small muscles attached to hair follicles; contraction causes 'goosebumps.'

Organism

Body Planes and Directional Terms

Understanding anatomical terminology is essential for describing locations and directions in the body.

• Body Planes: Imaginary lines dividing the body into sections (sagittal, coronal, transverse).

• Directional Terms: Terms such as anterior/posterior, superior/inferior, medial/lateral, proximal/distal are used to describe positions relative to the body.

Exam Structure and Grading

Overview of Final Exam Format

The final exam covers all topics from the semester and consists of 57 multiple-choice questions to be completed in 60 minutes. Grading is based on the percentage of correct answers, with a detailed breakdown provided for score ranges.

Additional info: The study guide covers foundational topics in Anatomy & Physiology, including chemistry, organ systems, tissues, and exam logistics. Students should review each topic in detail and understand key terms and processes for exam success.