Oral Anatomy & Histology (Review: Outcome 2) Flashcards
Anatomy
The scientific study of the shape and structure of the human body
Physiology
The study of the functions of the human body
Organizational levels of the body
- Cells form tissues
- Tissues form organs
- Organs form body systems
Cells
Basic units of structure in the human body
- React to stimuli
- Transform nutrients into energy
- Grow
- Reproduce
- The human body contains many types of cells: different shapes & functions
Basic components of a cell
- Cell membrane: protects the cell, acts as a filter
- Cytoplasm: watery, gel-like in which cell structures are suspended
- Ribosomes: proteins are assembled for use inside the cell
- Mitochondria: produce energy to keep cell going
- Lipid: fat droplets within cell
- Smooth endoplasmic reticulum: network of channels for moving substances within the cell
- Lysosomes: bags of digestive juices that break down nutrients& unwanted parts of the cell
- Chromosomes: carry cell’s genetic information
- Nucleus: the control center of the cell
- Golgi complex: where proteins made within the cell are packaged for export
- Microvilli: finger-like projections on surface of cell that increases surface area (cell’s ability to absorb)
Tissues
Formed when many millions of cells with the same shape, size, structure, and function join together to perform a specific function for the body
Types of Tissues
- Epithelial Tissues
- form a covering for the external (skin) and internal body surfaces (lining of the oral cavity and intestines) - Connective Tissues
- major support material of the body
- connects organs and tissues - Muscle Tissues
- has the ability to lengthen and shorten
- voluntary (e.g. arms, legs)
- involuntary (e.g. heart, lungs, stomach) - Nerve Tissues
- responsible for coordinating and controlling many body activities (brain, spinal cord, and nerves)
Organs
Formed when several types of tissues become a group and perform a single function
Body Systems
- Composed of a group of organs working together to perform a major function
- 10 systems; each has specific organs within in
- Each body system performs specific functions
Identify the different body systems
- Skeletal system
- Muscular system
- Cardiovascular system
- Nervous system
- Respiratory system
- Digestive system
- Endocrine system
- Urinary system
- Integumentary system
- Reproductive system
Skeletal System
Axial: 80 bones
Appendicular: 126 bones
Components:
- bones
- cartilage
- joints
Muscular System
- Gives us the ability to stand, walk, run, jump, move eyes, smile
- Composed of more than 600 individual muscles
- For muscles to make the body move, they must work together
- Each muscle consists of:
i. muscle tissue
ii. connective tissue
iii. nerve tissue
iv. vascular (blood) tissue
3 Types of Muscles
- Striated muscle (voluntary)
- dark & light bands in muscle fibers yield a striped/striated appearance
- skeletal/VOLUNTARY muscle
- attach to bones of skeleton; makes bodily motion possible - Smooth muscle (Involuntary)
- moves internal organs (e.g. digestive tract, blood vessels) - Cardiac muscle (Involuntary)
- forms most of the walls of the heart
Cardiovascular System
Consists of:
- Circulatory system
- Heart
- Lymphatic system
These systems provide life-sustaining capabilities for the survival of the body cells and tissues
- Transportation: oxygen & nutrients, CO2, hormones & antibodies
- Regulation (body temp., chemical stability)
Nervous System
Communication system of the body
- instructions and directions are sent out to various organs of the body
Divided into CNS & PNS:
CNS - brain & spinal cord
PNS - Divided into autonomic & somatic
- Autonomic is divided into parasympathetic (rest & digest) & Sympathetic (fight or flight)
Respiratory System
Delivers oxygen to millions of cells in the body and transports waste product CO2 out of the body
Consists of:
- nose
- paranasal sinuses
- pharynx
- epiglottis
- larynx
- trachea
- alveoli
- lungs
Digestive System
Provide the body with the nutrients, water, and electrolytes necessary for life
- Functions under involuntary control
Endocrine System
Consists of ductless glands and tissues that help regulate the body’s activities
- glands secrete hormones directly into the blood (hormones affect metabolism, growth, and development)
Urinary System (Excretory System)
- Principle function is to maintain fluid volume and composition of the body fluids
- Waste products leave the body in the form of urine and the needed substances are returned to the blood
Integumentary System (Skin System)
- The skin is the body’s first line of defense against disease
Functions:
- help regulate body temp.
- provides a barrier that prevents bacteria from entering the body
- excretes liquids and salts
- provides sensitivity to touch
- uses UV rays from sun to convert chemicals into vitamin D necessary for absorption of calcium
Reproductive System
Female:
- external & internal components
- internal: uterus, ovaries
Male:
- produces and transports sperm
The importance of interaction among the 10 body systems
Body systems do not operate independently
- exert important effects on each other
- something happening to one system tends to affect the other systems
Histology
The science/study of tissues
- from cells to tissues
What are tissues comprised of?
3 key components:
- cells
- intercellular substance
- tissue fluid
Epithelial Tissue
Definition: tissue type that covers & lines both external and internal body surfaces
Purpose:
- provides protection
- produces secretions
- regulates the passage of materials
2 types:
- covering & lining
- glandular or secretory
How do you describe epithelial tissues?
- Shape
- Squamous = flattened in shape
- Cuboidal = square in shape
- Columnar = tall and rectangular in shape - Arrangement
- Simple = single layer
- Stratified = multiple layers
- Psuedostratified = appears multi-layered but is single layer
Classification of Epithelium
- Simple
- squamous
- cuboidal
- columnar - Striated
- squamous
- cuboidal
- columnar
- transitional - Pseudostratified
- columnar
Basement Membrane
All lining and glandular epithelial tissue rests on connective tissue and is separated by a basement membrane
Types of Connective Tissues
- Specialized (Soft)
- Adipose (fat) - Supportive
- Bone (rigid)
- Tissue & cartilage (firm) - Dense (soft)
- ligaments
- tendons - Vascular (Fluid)
- blood
- lymph
Supportive Connective Tissue
a. Bone (osseous) tissue (rigid)
- protects and supports organs
b. Cartilage (firm, solid)
- firm flexible support
- serves as a shock absorber
Soft Connective Tissue
Specialized - Adipose (Fat)
- stores fat
- energy source (when needed)
- cushions. supports, insulates the body
Connective Tissue Proper (Soft)
i. Loose connective tissue
- protective padding for deeper structures
- ex. connective tissue papillae
ii. Dense connective tissue
- more tightly packed (strength)
- ex. dermis (under skin), tendons, ligaments
Vascular Connective Tissue
i. Blood tissue
- serves as transport medium for cellular nutrients
- defense systems
ii. Lymphatic tissue
- perform the functions of the lymphatic system (part of the immune system)
Muscle Tissue
3 divisions based on striations and muscle control:
a. smooth muscle tissue (involuntary control - spindle shaped)
- ex. walls of blood vessels
b. striated involuntary muscle tissue (rich in blood vessels)
- ex. Cardiac
c. striated voluntary muscle tissue (very strong)
- ex. skeletal muscle
Nerve Tissues
Nerves function to carry messages or impulses based on electrical potentials
- Afferent nerve (sensory nerve) = carries info or relays impulses from Periphery of body to the brain
- Efferent nerve (motor nerve) = carries info away from brain to the periphery of the body
Clinical significance of oral histology
i. The practice of dentistry is based on knowledge of:
- structure
- arrangement
- reaction
ii. Oral hygiene instruction (OHI) is based on:
- study of histology
- how cells react (how disease affects tissues)
- the amount of trauma tissues can withstand
iii. Disease caused by bacterial plaque biofilm is understood by the study of:
- tissue structure
- tissue reaction
- tissue repair
