Chapter 4- tissues and membranes
Define Tissue
A group of cells with a similar structure and function.
Membranes
sheets of tissue.
where are epithelial tissues found?
epithelial tissues are found on surfaces, as either coverings on an outer surface or linings of an inner surface. They receive oxygen and nutrients from the blood supply of the connective tissue beneath them.
what are epithelial tissues, sometimes called when they are capable of secretion?
gladular epithelium- glands
what are the three distinctive shapes of epithelial tissues?
squamous cells, cuboidal cells, and columnar. Simple is the term for a single layer of cells and saturated means that it's many layers.
simple squamous epithelium
is a single layer of flat cells. The cells are very thin and very smooth. An example of them are the Avioli air sacks of the lungs. Their thinness of cells permits, the diffusion of gases between the air and blood. Another example would be capillaries, the smallest blood vessels. capillary walls are only one cell thick, which permits the exchange of gases, nutrients and waste products between the blood and the tissue fluid.
saturated squamous epithelium
consists of many layers, mostly flat cells, although lower cells are rounded.
example of Saturated squamous, epithelium
lowest layer of the skin. Mitosis takes place to continually produce new cells to replace those worn off the surface. This type of epithelium makes up the epidermis of the skin, where it is called keratinizing because the protein keratin is produced, and the surface cells are dead.
what is transitional epithelium and an example of it?
transitional epithelium is a type of saturated epithelium in which the surface cells change shape from round to squamous. An example is the urinary bladder is lined with transitional epithelium. When the bladders empty the surface sells around. As the bladder fills, the cells become flattened. Transitional epithelium enables the bladder to fill and stretch without tearing the lining.
simple cuboidal epithelium and example.
is a single layer of cube shaped cells. this type of tissue makes up the functional units of the thyroid gland and salivary glands. These are examples of glandular epithelium. Their function is secretion.
what is a simple, columnar epithelium and an example?
Columnar cells Are taller than they are wide, and are specialized for the secretion and absorption. The stomach lining is made of columnar, epithelium and secrete gastric juice for digestion.
microvilli
Bold in the cell membrane on their free surface. These microscopic bones greatly increase the surface area for absorption.
goblet cell
another type of columnar cell, which is a unicellular gland. Goblet cells create secrete mucus, and are found in the lining of the intestines, and in the lining of parts of the respiratory tact, such as trachea.
ciliated epithelium
Consists of columnar cells that have swaths of motile cilia. their function is to sweep materials across the cell surface. these are found in the lines of the nasal cavity, larynx, trachea and large bronchial tubes.
Glands
our cells or organs that secrete something. That is they produce a substance that has a function, either at the site or at a more distance site.
unicellular glands and example
unicellular means one cell. Goblet cells are an example of unicellular glands.
multicellular glands and example.
Glands that are made of many similar cells or a variety of cells with their secretions mingled into a collective secretion. example: exocrine glads have ducts to take the secretion away from the gland to the site of its function. Salivary glands, for example secrete saliva that is carried by duct to the oral cavity. Sweat gland, secrete sweat that is transported by ducks to the skin surface where the sweat can be evaporated by excess body heat.
endocrine glands
endocrine glands are duckless glands. The secretions of an endocrine glands are a group of chemicals called hormones which enter capillaries and are circulated throughout the body. An example is thyroid gland.
hormones
hormones bring about specific effects in their target organs. These effects include aspects of growth, use of materials and other nutrients and regulation of blood pressure.
Types of connective tissue
Blood
Areolar- loose
Apipose
Fibrous
Elastic
Bone
Cartilage
strcture, location and function of blood
The structure of blood is a plasma, matrix and red blood cells, white blood cells, and platelets.
plasma- transports materials
RBCs- carry oxygen
WBCs- destroy pathogens
Platelets- prevent blood loss
Areolar structure, location and function
strcture- fibroblasts and a matrix of tissue fluid, collagen, and elastin fibers.
subcutaneous- Connect skin to muscles. WBCs destroy pathogens.
Below lining of mucous membranes. (digestive, Respiratory, urinary, Reproductive tracts) WBCs Destroy pathogens.
Adipose structure, location, and function
structure- Adipocytes that store fat (little matrix)
Subcutaneous adipose (white adipocytes) - Store excess energy and produce chemicals that influence, appetite, use of nutrients and inflammation.
Around eyes and kidneys – cushions
Brown generates heat (Brown and beige adipocytes) - An infants maintains body temperature. Also, amount increases in adults, who often exercise or are exposed to cold.
Fibrous structure, location, and function
structure- Mostly collagen fibers (Matrix) With few fibroblasts
Tendons and ligaments ( regular with parallel fibers) - Strong to withstand forces of movement of joints.
Dermis - (irregular with cross fibers) - The strong inner layer of the skin
elastic structure, location, and function
structure- Mostly, elastin fibers (matrix) with fre fibroblasts
With the walls of large arteries – helps maintain blood pressure. And around alveoli in lungs – promotes normal exhalation.
Bone
structure- osteocytes in a matrix of calcium salt and collagen
Bones- Supports the body and attach muscle. Protect internal organs from mechanical injury. Stores access calcium. Contains and protects red bone marrow.
cartilage, structure, location, and function
structure- Chondrocytes In a flexible, protein matrix.
Within the wall of the trachea – keeps airway open.
On joint surface of bones – smooth to prevent friction.
On nose and outer ear – support maintain shape.
Between vertebrae – absorb shock and permit movement.
Thermogenic
heat generating tissue in which cells, rapidly breakdown glucose, or fat and cell respiration.
Fibrillin
A protein that stabilizes the bundles of last and fibers in elastic connective tissue.
osteocytes
The prefix that designates bone is Osteo, so bone cells are called osteocytes.
Osteons or haversian systems
in the shafts of long bones, such as the femur, the osteocytes, matrix and blood vessels are in a very precise arrangement called osteons or haversian systems.
Chrondrocytes
Cartlidge cells in the matrix
Muscle Tissue
muscle tissue is specialized for contraction. When muscle cells also called muscle fibers or myocytes contract they shorten and bring about some type of movement.
what are the three types of muscle tissue?
Skeletal muscle
Smooth muscle
Cardiac muscle
skeletal tissue structure, location and function. Effective of nerve impulses.
Skeletal muscle may also be called striated muscle or voluntary muscle. They are structured as large cylindrical cells with striations and several nuclei each.
Skeletal muscle is attached to bones, and the function is to help move the skeleton and produce heat.
The effect of nerve impulses include essential to causing contraction (voluntary).
Smooth Muscle structure, location, and function. Also, what effects on nerve impulses?
Smooth muscle may also be called involuntary muscle or visceral muscle. They are structured as small tapered cells with no striations and one nucleus each.
They are within walls of arteries to maintain blood pressure.
Within the walls of the stomach and intestines. Peristalsis.
Also, in the iris of the eye which regulates the size of the pupil.
The effect of nerve impulses bring about contraction or regulate the rate of contraction (Involuntary).
cardiac muscle structure, location, and function. What effect on nerve impulses?
The cells of the heart, cardiac muscle, are branches cells that have one nucleus each and have faint striations.
Cardiac muscle forms the wall of the chambers of the heart in order to pump blood.
The effect of nerve impulses includes regulate only the rate of contraction (involutary).
intercalated discs
cell membranes at the end of the cardiac muscle that are extensively folded and fit into matching folds of the membranes of the next cell. These interlocking folds are called inter, collated discs and permit the electrical impulses of muscle contraction to pass swiftly from cell to cell. This enables the heart to beat.
myocardium
Cardiac muscle as a whole is called myocardium. forms the wall of the atria and ventricles, the four main chambers of the heart. It's function is to pump blood.
nerve tissue
Nerve tissue consists of nerve cells called neurons, and some specialized cells found only in the nervous system.
what are the two Divisions of the nervous system?
The central nervous system (CNS), and the peripheral nervous system (PNS).
what parts of the body are made by nerve tissue?
The brain, spinal cord and peripheral nerves.
what are the 4 parts of nerve tissue?
neuron
synapse
neurotransmitters
Neurolgia
Schwann cell
what is the structure and function of a neuron? Cell body, Axon and Dendrites?
Cell body- Contains the nucleus
Function – regulates the functioning of the neuron
Axon - Cellular process (Extension)
Function- Carries electrical impulses away from the cell body.
Dentrites- Cellular process (extension)
Function: Carrie electrical impulses toward the cell body.
what is the structure and function of synapse?
The structure of synapse Our space between axon of one neuron, and the dentrite or cell body of the next neuron.
function- Transmits impulses from one neuron to others, by means of chemicals.
what is the structure and function of neurotransmitters?
structure- Chemicals released by axons
function- Transmit Impulses across synapses
what is the structure and function of neurolgia?
structure- specialized cells in the central nervous system.
function- form myelin sheaths And other functions.
what is the structure and function of Schwann cells?
Structure – specialized cells in the peripheral nervous system
function- Form the Mylin sheaths around the neurons
Membrane
membranes are sheets of tissue that cover or line surfaces, that separate organs or parts (lobes) of organs from one another.
what are the two major categories of membranes?
Epithelial membranes and connective tissue membranes.
what are the two types of epithelial membranes?
Serous membranes and mucous membranes
serous membranes
are sheets of simple squamous epithelium that line some Closed body cavities and cover the organs in these cavities.
pleural membranes
These are serous membranes of the thoracic cavity. They line the chest wall, and the visceral pleural covers the lungs.
serous fluid
The pleural membranes, secrete serous fluid, which prevents friction between them as the lungs, expand and recoil during breathing.
pericardium
The parirtal pericardium lines, the fibrous pericardium, a connective, tissue membrane, and the visceral pericardium or epicardium is on the surface of the heart muscle.
peritoneum
is the serous membrane that lines the cavity in the abdomen.
mesentery
or visceral
peritoneum, is folded over and covers the abdominal organs.
mucous membranes
Lines the body tract systems that have openings to the environment. These are the respiratory digestive urinary and Reproductive tracts.
mucousa
The epithelial lining of a body cavity that opens to the environment.
mucus
secreted by these membranes, keeping the lining of the epithelial cells, wet.
what is a connective tissue membrane?
membranes made of connective tissue that cover and line the Body cavities.
what are the 7 types of connective tissue membranes?
Superficial fascia
Periosteum
Perichondrium
Synovial
Deep fascia
Meninges
Fibrous pericardium
superficial fascia- location and function
between the skin and muscle; adipose tissue stores fat; white blood cells destroy pathogens that enter breaks in the skin.
periosteum
covers each bone, contains blood vessels that enter the bone, anchors tendons from muscles and ligaments from other bones
perichondrium location and function
covers Cartlidge, contains capillaries, the only blood supply for Cartlidge
Synovial location and function
Lines, joint cavities, secretes, synovial fluid to prevent friction when joints move
deep fascia location and function
covers each skeletal muscle and anchors tendons
Meninges
covers the brain and spinal cord lines. The cranial and spinal cavities contains cerebrospinal spinal fluid.
Fibrous pericardium
forms of sack around the heart lined by the serous parietal pericardium