Anatomy Final Review

Overview of Anatomy and Physiology Anatomy – the study of the structure of body parts and their relationships to one another Gross or macroscopic Microscopic Developmental Physiology – the study of the function of the body’s structural machinery

Organ System Interrelationships The integumentary system protects the body from the external environment Digestive and respiratory systems, in contact with the external environment, take in nutrients and oxygen

Homeostasis Homeostasis is the ability to maintain a relatively stable internal environment in an ever-changing outside world The internal environment of the body is in a dynamic state of equilibrium Chemical, thermal, and neural factors interact to maintain homeostasis

Homeostatic Control Mechanisms Variable produces a change in the body Receptor monitors the environments and responds to changes (stimuli) Control center determines the set point at which the variable is maintained Effector provides the means to respond to the stimulus

Figure 1.4

Directional Terms Table 1.1

Directional Terms Table 1.1 (continued)

Directional Terms Table 1.1 (continued)

Body Planes Figure 1.8

4 basic tissue types

Epithelial tissue Functions: 1. Protection from physical & chemical injury 2. Protection against microbial invasion 3. Contains receptors which respond to stimuli 4. Filters, secretes & reabsorbs materials 5. Secretes serous fluids to lubricate structures

Epithelial tissue

Characteristics of connective tissue Farther apart than epithelium Contain an “extracellular matrix” consisting of fibers and ground substance Vascular

Muscle Tissue Skeletal Cardiac Smooth Muscles attached to bones Voluntary, multiple nuclei, striations Cardiac Muscle tissue of the heart Involuntary, single nucleus, striations, intercalated discs Smooth Walls of hollow internal organs Involuntary, single nucleus, spindle-shaped cells

Nervous Tissue Location: Main component of the nervous system, i.e., brain, spinal cord & nerves Functions: Regulates & controls body functions Generates & transmits nerve impulses Supports, insulates and protects impulse generating neurons

Integumentary System

Epidermis

Dermis

Hypodermis

Skin Color Determined by: Pigments (melanin, carotene) Blood circulation Thickness of stratum corneum

Skin Glands Sudoriferous (sweat) Sebaceous (oil) Eccrine (skin surface) and Apocrine (hair follicle) Eccrine: widely distributed Apocrine: found in anogenital and axillary regions Sebaceous (oil) Produce oil for waterproofing Empty into hair follicles

Skeletal System Functions Support – form the framework that supports the body and cradles soft organs Protection – provide a protective case for the brain, spinal cord, and vital organs Movement – provide levers for muscles Mineral storage – reservoir for minerals, especially calcium and phosphorus Blood cell formation – hematopoiesis occurs within the marrow cavities of bones

Type of Bones Long bones – i.e. humerus and femur Short bones – i.e. patella and ankle and wrist bones Flat bones – i.e. sternum and most skull bones Irregular bones – i.e. vertebrae and hip bones

Chemical composition of bone Osteoblasts – bone-forming cells Osteocytes – mature bone cells Osteoclasts – large cells that reabsorb or break down bone matrix

Functions of Muscular System Produce movement Maintain posture Stabilize joints Generate heat

Neuromuscular Junction

Sliding Filament Theory

Muscle Movement Muscles are attached to at least two points Origin – attachment to a moveable bone Insertion – attachment to an immovable bone

Nervous System 1. Sensory input – gathering information To monitor changes occurring inside and outside the body (changes = stimuli) 2. Integration – to process and interpret sensory input and decide if action is needed. 3. Motor output A response to integrated stimuli The response activates muscles or glands

Divisions of Nervous System CNS – brain and spinal cord; integration center PNS – nerves outside the brain and spinal cord; sensory input and motor output

Nerve Impulse (Action Potential) Depolarization – a stimulus depolarizes the neuron’s membrane A depolarized membrane allows sodium (Na+) to flow inside the membrane The exchange of ions initiates an action potential in the neuron