Anatomy/physiology chapter 4
Epithelial cells consists of an apical surface, an epithelial cells portion, basal surface and a basement membrane. What is the function(s) of the basement membrane?
1. Serves as a structural attachment site between the epithelium and the underlying connective tissue. 2. It provides a guide for migration and growth of epithelial cells during development. 3. It acts as a filtration barrier to substances moving between epithelium and connective tissue.
Belt like junction anchored to a dense plaque of proteins inside the cell and helps to resist the separation of epithelial tissue. They connect other cells together.
Adherens junctions
Two ways in which epithelial cells are classified
Arrangement of cells in layers and cell shapes
Liquid connective tissue gives rise to blood tissue and lymph. Describe the location and function of blood tissue (or blood)
Blood lies within blood vessels (arteries, capillaries, veins) and within chambers of the heart. It functions to transport oxygen, carbon dioxide and white blood cells essential to the immune response.
Why does damaged cartilage heal so slowly?
Cartilage is avascular, therefor materials needed for repair must be brought in from surrounding tissues.
What type of connective tissue consists of parallel bundles of collagen fibres and fibroblasts and forms tendons, most ligaments and aponeuroses?
Dense regular connective tissue
Forms connecting bridges between cells with intermediate finger like filaments, contribute to cell stability and are most numerous in the epidermis. Also attached to intracellular plaque.
Desmosome
What are the 4 types of tissues in the body?
Epithelial Connective Muscular Nervous
An open communication channel that allow the passage of nerve impulses, ions and small molecules to pass from one cell to another. Abundant in cardiac and smooth muscle
Gap junction
What type of cell junction would be required for cells to communicate with one another?
Gap junction
Location and Function of Areolar connective tissue
Located in and around nearly every body structure - known as "packing material" of the body. Functions for Strength, elasticity and support.
Location and function of elastic connective tissue
Located in the lung tissue, walls of elastic arteries, trachea and bronchial tubes and functions to allow stretching of various organs as it is strong and can recoil to its original shape after being stretched
Location and Function of reticular connective tissue
Located in the stroma of liver, spleen, lymph nodes etc. And functions to form the stroma of organs, binds smooth muscle cells and filters/removes worn out blood cells
Location and function of elastic cartilage
Located on top of larynx, part of the ear and auditory tubes. Provides strength and elasticity.
Location and Function of adipose tissue
Located wherever Areolar connective tissue is located and functions to Reduce heat loss through skin, serves as an energy reserve, supports and protects organs
Describe skeletal muscle tissue
Long, cylindrical, striated fibres. Skeletal muscle is voluntary and is usually attached to bones by tendons. It functions to provide motion, posture, heat and protection.
What is a connective tissues extra cellular matrix?
Material located between widely spaced cells consisting of protein fingers and ground substance
What type of exocrine gland forms its secretory product and simply releases it from the cell by exocytosis?
Merocrine gland
Appears to have multiple layers of cells however it is actually a single layer as not all of the cells reach the apical surface
Pseudo stratified epithelium
Ciliated variety secrets mucus to trap foreign particles and help sweep mucus across the apical surface. It lines the airways of most of the upper respiratory tract. Nonciliated variety functions in absorption and protection. It lines ducts of many glands and part of the male urethra.
Pseudo stratified epithelium
Location and function of fibrocartilage
Pubic symphysis, intervertebral discs, knee meniscus and functions to support and joint structures together.
What do exocrine glands secrete?
Secretory products that empty onto a surface such as the skin or lumen of a hallow organ.
This epithelium can be ciliated or nonciliated and lines the stomach, small and large intestines, gallbladder and rectum (the gastrointestinal tract) It's ciliated form lines the uterus, some respiratory air passages and sinuses, the central canal of the spinal cord and ventricles of the brain
Simple columnar
This type of epithelium functions in secretion, absorption, and as a barrier for protection. It can be ciliated or nonciliated.
Simple columnar epithelium
This epithelium functions in secretion, absorption, and as a barrier for protection. It covers the surface of ovaries, lines the anterior surface of the lens of the eye, kidney tubules and smaller ducts of many glands such as the thyroid.
Simple cuboidal epithelium
Single layer of cells
Simple epithelium
3 types of cell arrangements
Simple epithelium - single layer Stratified epithelium - two or more layers Pseudostratified epithelium - single layer that appears to be many layers
List the 8 types of epithelial tissues
Simple squamous Simple cuboidal Simple columnar Pseudo stratified Stratified squamous Stratified cuboidal Stratified columnar Transitional
Most commonly lines the cardiovascular and lymphatic system and forms the epithelial layer of the serous membrane where it's called the mesothelium
Simple squamous epithelium
This epithelium is specialized for diffusion, osmosis, filtration and secretion. (In serous membranes) it lines the pericardium, alveoli in the lungs and the linings of the heart, blood and lymphatic vessels.
Simple squamous epithelium
Why are neurons and muscle fibres considered excitable cells
They exhibit electrical excitability
This epithelium is specialized for protection and secretion and is found in the larger ducts of some glands, portions of the urethra and in small areas in the anal mucus membrane.
Stratified columnar epithelium
This type of epithelium is specialized for protection and some secretion and absorption. It is found in the ducts of adult sweat and esophogeal glands and portions of the male urethra and developing ovarian follicles.
Stratified cuboidal epithelium
Multiple layer of cells
Stratified epithelium
Which of the types of tissues is avascular? -Cardiac muscle -Stratified squamous epithelial -Compact bone -Skeletal muscle -Adipose tissue
Stratified squamous epithelial tissue is avascular
The functions of this type of epithelial tissue is to provide protection against abrasion, water loss and uv radiation. First line of defence against foreign microbes. The keratinized variety forms superficial layer of the skin; Non-Keratinized variety lines all wet surfaces (mouth, esophagus, vagina, tongue)
Stratified squamous epithelium
Junctions that prevent the transport of contents of an organ such as the intestines, stomach and urinary bladder
Tight junction
Type of junction with web-like strands that seal off the passageway between adjacent cells
Tight junction
What is the function of exocrine glands?
To produce substances such as sweat that help lower body temperature to maintain homeostasis.
Multiple layer of cells that vary in shape
Transitional epithelium
This epithelium tissue provides distension for organs that change volume.
Transitional epithelium
Describe the location of exocrine glands?
Sweat glands on skin Oil and earwax glands on skin Digestive (salivary glands) and pancreas
What is the function of the basement membrane in epithelial tissue?
The basement membrane provides support for the epithelium and plays a part in growth and wound healing, restriction of molecule movement between tissues and blood filtration in the kidneys.
What is the function of endocrine glands?
The hormones secreted by endocrine glands help regulate many metabolic activities to maintain homeostasis
What is the major difference between epithelial and connective tissue?
The number of cells - epithelial with many cells tightly packed together while connective tissue with few cells scattered between extra cellular matrix.
Describe the structure and function of the 4 tissue types
-Epithelial tissues cover the body, line various structures and form glands. -Connective tissues protect, support, bind organs together, store energy and help with immunity. -Muscular tissue contracts and generates force and heat. -Nervous tissue detects changes in the environment and generates nerve impulses that activate muscular contraction and glandular secretions.
List the 5 types of mature connective tissue
-Loose connective tissue -Areolar connective tissue -Adipose tissue -Reticular connective tissue -Dense connective tissue -Dense regular connective tissue -Dense irregular connective tissue -Elastic connective tissue -Cartilage -Hyaline cartilage -Fibrocartilage -Elastic cartilage -Bone tissue -Liquid connective tissue -Blood tissue -Lymph
What are the two types of embryonic connective tissue?
-Mesenchyme -Mucous connective tissue
What are the three main functions of epithelial tissues?
-They serve as selective barriers that limit or aid the transfer of substances into or out of the body -They serve as secretory surfaces that release products produced by cells onto their free surface -They serve as a protective surface that resists the abrasive environment.
What is the function of the apical surface?
1. Increases the surface area for absorption (via microvilli) 2. It is the exposed part to the external (body cavity) and internal (a hallow organ) environment.
What are the two basic elements of connective tissue?
Extra cellular matrix and cells
What are the six types of cells in connective tissue?
Fibroblasts- in loose and dense connective Adipocytes - connective tissue cells that store fat Mast cells - produce histamine for inflammatory response White blood cells - migrate to connective tissue in response to infections etc Macrophages - capable of engulfing bacteria Plasma cells - antibodies that attack foreign substances
Location and function of dense regular connective tissue
Forms tendons, most ligaments and aponeuroses and functions as a strong attachment between various structures
Describe cardiac muscle tissue
Found only in the heart wall, cardiac muscle is branched and striated. It pumps blood to all parts of the body.
If an organ produced mucus, what type of cell would be found lining the tissue of that organ?
Goblet cells
Looks like half of a desmosome and attaches cells to the basement membrane. They function to connect a cell to another cell or structure
Hemidesmosome
What do endocrine glands secrete?
Hormones
Cartilage gives rise to hyaline cartilage, Fibrocartilage and elastic cartilage. What is the Location and function of hyaline cartilage?
Hyaline cartilage is the most abundant cartilage in the body located at the ends of all long bones, ribs, nose and fetal skeleton. Its job is to provide smooth surfaces for movement at joints, provide flexibility and support.
Describe the location and function of Mesenchyme cells of embryonic connective tissue
Mesenchyme cells are irregularly shaped cells located almost exclusively under skin along developing bones of the embryo and along blood vessels. They function to form almost all other types of connective tissue
Describe the function and location of mucous connective tissue
Mucous connective tissue is widely scattered fibroblasts embedded in viscous, jelly like substance located in the umbilical cord of the fetus. It functions to support the fetus.
What are connective tissues supplied with?
Nerves. They are highly vascular and have a rich blood supply.
What are the two types of nervous tissue
Nervous system is composed of nerve cells (neurons) and neuralgia (protective and supporting cells
Location and function of dense irregular connective tissue
Often occurs in sheets such as fascia, deeper region of the dermis, pericadium of the heart, around joint capsules and capsules around many organs. It functions to provide tensile strength in many directions.
Which type of muscular tissue can be voluntarily controlled?
Skeletal
What are the three types of muscle tissue?
Skeletal muscle tissue Cardiac muscle tissue Smooth muscle tissue
Describe smooth muscle tissue
Smooth muscle fibres are involuntary, nonstriated and are small and spindle shaped. The are located in the iris of the eyes, airways to lungs, stomach, intestines, gallbladder etc and function to move food through the GI tract
What cell shape is best adapted for the rapid movement of substances from one cell to another
Squamous cells
4 types of cell shapes
Squamous cells -flat, thin allow for quick passage Cuboidal cells - cubes/hexagons secretion/absorb Columnar cells- like columns, secretion/absorption Transitional cells - change shape.