2 Discuss the three types of cell junctions. Give the type and the function.
3. Find and on-line example of a Fluid Mosaic diagram, then paste it into your post.
A well developed answer will receive 25 points.
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Tissues-Cells group together in the body to form tissues - a collection of similar cells that group together to perform a specialized function.
Organs-is a structure that contains at least two different types of tissue functioning together for a common purpose.
Organ Systems-Organ systems are composed of two or more different organs that work together to provide a common function.
Facts found at http://web.jjay.cuny.edu/~acarpi/NSC/14-anatomy.htm
Three types of cell junctions are:
* occluding junctions: function to seal cells together in an epithelial sheet
* adhesive junctions: mechanically attach cells to one another or to the ECM
* communicating junctions: allow direct passage of chemical or electrical signals from cell to cell
Found at http://www.esf.edu/efb/course/efb325/lectures/junctions.htm
Tissue is a cellular organizational level intermediate between cells and a complete organism. Hence, a tissue is an ensemble of cells, not necessarily identical, but from the same origin, that together carry out a specific function. Organs are then formed by the functional grouping together of multiple tissues.
The study of tissue is known as histology or, in connection with disease, histopathology.
The classical tools for studying tissues are the paraffin block in which tissue is embedded and then sectioned, the histological stain, and the optical microscope. In the last couple of decades, developments in electron microscopy, immunofluorescence, and the use of frozen tissue sections have enhanced the detail that can be observed in tissues. With these tools, the classical appearances of tissues can be examined in health and disease, enabling considerable refinement of clinical diagnosis and prognosis.
In biology, an organ (Latin: organum, "instrument, tool", from Greek όργανον - organon, "organ, instrument, tool") is a group of tissues that perform a specific function or group of functions. Usually there is a main tissue and sporadic tissues. The main tissue is the one that is unique for the specific organ. For example, main tissue in the heart is the myocardium, while sporadic are the nerves, blood, connective etc.
Animal organs
Animal organs include the heart, lungs, brain, eye, stomach, spleen, bones, pancreas, kidneys, liver, intestines, skin (the largest human organ), urinary bladder, and the sex organs (uterus in female animals, testicles in male). The internal organs collectively are often called viscera, the plural of the rarely-used term viscus.
[edit] Plant organs
Plant organs can be divided into vegetative and reproductive. Vegetative plant organs are root, stem and leaf, while reproductive are flower, seed and fruit.
The vegetative organs are essential for maintaining the life of a plant (they preform the vital functions, such as photosynthesis), while the reproductive organs are essential in reproduction. But, if there is asexual vegetative reproduction, the vegetative organs are those which create the new generation of plants (see clonal colony).
[edit] Organ systems
Main article: Biological system
A group of related organs is an organ system. Organs within a system may be related in any number of ways, but relationships of function are most commonly used. For example the urinary system comprises organs that work together to produce, store, and carry urine.
The functions of organ systems often share significant overlap. For instance, the nervous and endocrine system both operate via a shared organ, the hypothalamus. For this reason, the two systems are combined and studied as the neuroendocrine system. The same is true for the musculoskeletal system, which involves the relationship between the muscular and the skeletal system.
-http://en.wikipedia.org/wiki/Organ_(anatomy)
Three types of cell junctions are:
* occluding junctions: function to seal cells together in an epithelial sheet
* adhesive junctions: mechanically attach cells to one another or to the ECM
* communicating junctions: allow direct passage of chemical or electrical signals from cell to cell
Found at http://www.esf.edu/efb/course/efb325/lectures/junctions.htm
1.Tissue is a cellular organizational level intermediate between cells and a complete organism. Hence, a tissue is an ensemble of cells, not necessarily identical, but from the same origin, that together carry out a specific function. Organs are then formed by the functional grouping together of multiple tissues.
Organ systems are composed of two or more different organs that work together to provide a common function.
http://en.wikipedia.org/wiki/Biological_tissue
http://web.jjay.cuny.edu/~acarpi/NSC/14-anatomy.htm
2. Three types of cell junctions are:
A.Gap junctions are between adjacent cells that allow passage of small molecules and facilitate cell-cell communication.
B.Tight junctions function to form a seal between adjacent cells and also define the apical and basal sides of an epithelial cell.
C.Anchoring junctions mechanically attach cells(and their cytoskeletons)to their neighbors or the extracellular matrix.
3.http://faculty.southwest.tn.edu/rburkett/GB1-os10.jpg
1.)the differnece between tissues, organs, and organ systems are that a tissue is a collection of cells with similar functions, an organ is made up of many different tissues that work together for a common function the stomach is an organ made up of muscel tissue. and organ system is a system which consists of different organs that work together in an operation.
http://answers.yahoo.com/question/ index?qid=20071211001809AAlQyz2
2.)OCCLUDING JUNCTIONS: function to seal cells together in an epithelial sheet ADHESIVE JUNCTIONS: mechanically attach cells to one another or to the ECM. COMUNICATING JUNCTIONS: allow direct passage of chemical or electrical signals from cell to cell.
3.)http://upload.wikimedia.org/wikipedia/commons/thumb/b/b6/Cell_membrane_detailed_diagram.svg/877px-Cell_membrane_detailed_diagram.svg.png
1.Tissues
Cells group together in the body to form tissues - a collection of similar cells that group together to perform a specialized function. There are 4 primary tissue types in the human body: epithelial tissue, connective tissue, muscle tissue and nerve tissue.
Organ
a structure that contains at least two different types of tissue functioning together for a common purpose.
Organ System
composed of two or more different organs that work together to provide a common function.
http://web.jjay.cuny.edu/~acarpi/NSC/14-anatomy.htm
2.Tight Junction-provides sealed barrier
Adherens Junction-binds together microfilaments between adjacent cells
Desmosome-binds intermidiate filaments of adjacent cells
3.http://www.harlem-school.com/10TH/sci_pdf/graphics/fluid_mosaic.gif
1. TISSUE is a cellular organizational level intermediate between cells and a complete organism. Hence, a tissue is an ensemble of cells, not necessarily identical, but from the same origin, that together carry out a specific function. ORGANS are then formed by the functional grouping together of multiple tissues. An organ is a group of tissues that perform a specific function or group of functions. An ORGAN SYSTEM is a group of related organs. http://en.wikipedia.org/wiki/Biological_tissue
http://en.wikipedia.org/wiki/Organs
http://en.wikipedia.org/wiki/Organ_(anatomy)#Organ_systems
2. - Anchoring junctions- mechanically attach the cytoskeleton of the cell to the cytoskelelton of another.
- Adherens junction- the interacellular end of the of the cadheren molecule binds to a cadherin molecule in the adjacent cell.
- Tight junctions- are found predominantly in tissues of cells that form the lining of organs such as the stomach where a tight sealed barrier is needed.
3.Fluid mosaic website http://upload.wikimedia.org/wikipedia/commons/thumb/b/b6/Cell_membrane_detailed_diagram.svg/877px-Cell_membrane_detailed_diagram.svg.png
1)Tissue is a group of cells that have similar structure and that function together as a unit. An organ is a structure that contains at least two different types of tissue functioning together for a common purpose. Organ systems are composed of two or more different organs that work together to provide a common function.(www.training.seer.cancer.gov) (web.jjay.cuny.edu)
2)The first is the Tight junction. It provides sealed barrier. The second is the Adherens junction. It binds together microfilaments between adjacent cells. The last one is the Gap junction. It allows passage of ions and small molecules between adjacent cells.
3)You can find a picture at waynesword.palomar.edu.
1.)Tissues are groups of specialized cells that are together to carry a specific function they could not do seperatly. There are four different types of tissues;epithelial tissue, connective tissue, muscle tissue and nerve tissue.Organs are a group of tissues that are working to create a special function. Organs are the heart, liver, kidneys, gallbladder,pancreas etc.
Organ systems are a group of organs that work to acheive a common function. There are ten organ systems, skeletal, endocrine, digestive, nervous,etc.
2.)Tight, anchoring, and gap.
tight-provides sealed barrier
anchoring- attaching to side of the cell to another
gap- provides a narrow passageway between cells to share molecules and ions.
3.) http://www.harlem-school.com/10TH/sci_pdf/graphics/fluid_mosaic.gif
1. Tissues are the cellular organizational level intermediate between cells and a complex organisms, and Organs are a group of tissues that perform a specific function or group functions, and organs systems are bones, cartilage,tendons,ligaments
http://web.jjay.cuny.edu/~acarpi/NSC/14-anatomy.htm
2.Tight Junction-Provides sealed barrier.
Gap Junction- allows passage of ions and small molecules between adjacent cells.
adherens junctions- Binds together microsfilaments between adjacent cells.
3.http://upload.wikimedia.org/wikipedia/commons/thumb/b/b6/Cell_membrane_detailed_diagram.svg/877px-Cell_membrane_detailed_diagram.svg.png
were the diagram is
1. Use on-line web sources to distinguish between tissues, organs, and organ systems. Give your source at the end of your findings.
Tissue is a cellular organizational level intermediate between cells and a complete organism. Hence, a tissue is an ensemble of cells, not necessarily identical, but from the same origin, that together carry out a specific function. Organs are then formed by the functional grouping together of multiple tissues.The human body is made up of several organ systems that work together as one unit. Examples are circulatory, respiratory, and nervous system are just a few.( Wickapedia, About. com)
2 Discuss the three types of cell junctions. Give the type and the function.
Tight Junction-provides sealed barrier
Adherens junstiion- binds together microfilaments beteewn adjacent cells
Desmosome- binds intermediate filaments of adjacent cells
Gap junction-Allows passage of ions and small molecules beteewn adjacent cells.
3. Find and on-line example of a Fluid Mosaic diagram, then paste it into your post. http://images.google.com/imgres?imgurl=http://upload.wikimedia.org/wikipedia/commons/thumb/b/b6/Cell_membrane_detailed_diagram.svg/877px-Cell_membrane_detailed_diagram.svg.png&imgrefurl=http://en.wikibooks.org/wiki/A-level_Biology/Biology_Foundation/cell_membranes_and_transport&h=361&w=877&sz=227&hl=en&start=8&um=1&usg=__tmRV9VbkuAihkgtFcSQwOPUNudA=&tbnid=inCPkVwPcQUp6M:&tbnh=60&tbnw=146&prev=/images%3Fq%3Dfluid%2Bmosaic%2Bdiagrams%26um%3D1%26hl%3Den%26client%3Dsafari%26rls%3Den-us%26sa%3DX
1. Tissue is a collection of similar cells that group together to perform a specialized function. An organ is a structure that contains at least two different types of tissue functioning together for a common purpose. Organ systems are composed of two or more
different organs that work together to provide a common function.http://web.jjay.cuny.edu/~acarpi/NSC/14-anatomy.htm
2. tight juction- provides sealed barrier
Adherents juntion- Binds together microfilaments between adjacent cells
Desmosome- Binds intermediate filaments of adjacent cells
3.http://upload.wikimedia.org/wikipedia/commons/thumb/b/b6/Cell_membrane_detailed_diagram.svg/877px-Cell_membrane_detailed_diagram.svg.png
1. Cells group together in the body to form tissues - a collection of similar cells that group together to perform a specialized function. There are 4 primary tissue types in the human body: epithelial tissue, connective tissue, muscle tissue and nerve tissue.
Organs are the next level of organization in the body. An organ is a structure that contains at least two different types of tissue functioning together for a common purpose. There are many different organs in the body: the liver, kidneys, heart, even your skin is an organ.
Organ systems are composed of two or more different organs that work together to provide a common function. There are 10 major organ systems in the human body
http://web.jjay.cuny.edu/~acarpi/NSC/14-anatomy.htm
2. TIGHT JUNCTIONS- Epithelia are sheets of cells that provide the interface between masses of cells and a cavity or space (a lumen).
* The portion of the cell exposed to the lumen is called its apical surface.
* The rest of the cell (i.e., its sides and base) make up the basolateral surface.
Tight junctions seal adjacent epithelial cells in a narrow band just beneath their apical surface.
Tight junctions perform two vital functions:
* They prevent the passage of molecules and ions through the space between cells. So materials must actually enter the cells (by diffusion or active transport) in order to pass through the tissue. This pathway provides control over what substances are allowed through.
* They block the movement of integral membrane proteins (red and green ovals) between the apical and basolateral surfaces of the cell.
ADHEREN JUNCTIONS-
Adherens junctions provide strong mechanical attachments between adjacent cells.
* They hold cardiac muscle cells tightly together as the heart expands and contracts.
* They hold epithelial cells together.
* They seem to be responsible for contact inhibition.
* Some adherens junctions are present in narrow bands connecting adjacent cells.
* Others are present in discrete patches holding the cells together.
Adherens junctions are built from:
* cadherins — transmembrane proteins (shown in red) whose
o extracellular segments bind to each other and
o whose intracellular segments bind to
* catenins (yellow). Catenins are connected to actin filaments
Inherited mutations in a gene encoding a cadherin can cause stomach cancer. Mutations in a gene (APC), whose protein normally interacts with catenins, are a common cause of colon cancer. Loss of functioning adherens junctions may also lead to tumor metastasis.
GAP JUNCIONS- are intercellular channels some 1.5–2 nm in diameter. These permit the free passage between the cells of ions and small molecules (up to a molecular weight of about 1000 daltons).
They are cylinders constructed from 6 copies of transmembrane proteins called connexins.
Because ions can flow through them, gap junctions permit changes in membrane potential to pass from cell to cell.
Examples:
* The action potential in heart (cardiac) muscle flows from cell to cell through the heart providing the rhythmic contraction of the heartbeat.
* At some synapses in the brain, gap junctions permit the arrival of an action potential at the synaptic terminals to be transmitted across to the postsynaptic cell without the delay needed for release of a neurotransmitter.
* As the time of birth approaches, gap junctions between the smooth muscle cells of the uterus enable coordinated, powerful contractions to begin.
3. http://fig.cox.miami.edu/~cmallery/150/memb/c8.7x7.fluid.mosaic.jpg
1. Cells group together in the body to form tissues - a collection of similar cells that group together to perform a specialized function. There are 4 primary tissue types in the human body: epithelial tissue, connective tissue, muscle tissue and nerve tissue. Organs are the next level of organization in the body. An organ is a structure that contains at least two different types of tissue functioning together for a common purpose.Organ systems are composed of two or more different organs that work together to provide a common function. so altogether these three things are pretty similar but if u can tell that there are tiny differences in them.http://web.jjay.cuny.edu/~acarpi/NSC/14-anatomy.htm
2. Tight junctions perform two vital functions:
* They prevent the passage of molecules and ions through the space between cells. So materials must actually enter the cells (by diffusion or active transport) in order to pass through the tissue. This pathway provides control over what substances are allowed through.
* They block the movement of integral membrane proteins (red and green ovals) between the apical and basolateral surfaces of the cell. Thus the special functions of each surface.
Adherens junctions provide strong mechanical attachments between adjacent cells.
Gap junctions are intercellular channels some 1.5–2 nm in diameter. These permit the free passage between the cells of ions and small molecules (up to a molecular weight of about 1000 daltons).
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/J/Junctions.html#gap
3. http://fig.cox.miami.edu/~cmallery/150/memb/c8.7x7.fluid.mosaic.jpg
The fluid mosaic is basically a structure made of many different parts.
1.Biological tissue is a collection of interconnected cells that perform a similar function within an organism.A organ is a a function in your body that makes you live.A organ system is a group of organs working together.
2.The 3 cell junctions are tight,anchoring,and gap junction.Tight are found predominantly in a tissues of cells that form the linings of organs such as the a stomach. Anchoring mechanically attach the cytoskeleton of one cell to the cytoskeleton of another. Gap junction it serves a very different purpose.
3.http://images.google.com/imgres?imgurl=http://www.tulane.edu/~biochem/faculty/facfigs/fluid_mosaic.gif&imgrefurl=http://www.tulane.edu/~biochem/faculty/facfigs/fluid_mosaic.htm&h=235&w=539&sz=50&hl=en&start=12&um=1&usg=__BHjIcY8ORwss5xgvMv-k0XcUoUA=&tbnid=wNWkKZKTwNk3tM:&tbnh=58&tbnw=132&prev=/images%3Fq%3DFluid%2BMosaic%26um%3D1%26hl%3Den%26client%3Dfirefox-a%26rls%3Dorg.mozilla:en-US:official%26sa%3DX
1. Cells group together in the body to form tissues - a collection of similar cells that group together to perform a specialized function. An organ is a structure that contains at least two different types of tissue functioning together for a common purpose.Organ systems are composed of two or more different organs that work together to provide a common function.
2. The three types of cell junctions are tight junction- provides sealed barrier. Adherens junction- binds together microfilament between adjacent cells. Gap junction- allows passage of ions and small molecules between adjacent cells.
3. http://images.google.com/imgres?imgurl=http://upload.wikimedia.org/wikipedia/commons/thumb/b/b6/Cell_membrane_detailed_diagram.svg/877px-Cell_membrane_detailed_diagram.svg.png&imgrefurl=http://en.wikibooks.org/wiki/A-level_Biology/Biology_Foundation/cell_membranes_and_transport&h=361&w=877&sz=227&hl=en&start=2&um=1&usg=__Ry8e6CECPsCoKV4QQfXMCuyerKM=&tbnid=inCPkVwPcQUp6M:&tbnh=60&tbnw=146&prev=/images%3Fq%3DFluid%2BMosaic%2Bdiagram%26um%3D1%26hl%3Den%26client%3Dfirefox-a%26channel%3Ds%26rls%3Dorg.mozilla:en-US:official%26sa%3DN
Emily Norris
1. http://web.jjay.cuny.edu/~acarpi/NSC/14-anatomy.htm
2. cells group together to form tissue. and organ is a strusture that contains two types of similar tissue's. organ systems contain two or more types of diffrent tissues.
3. http://images.google.com/imgres?imgurl=http://www.nature.com/horizon/livingfrontier/background/images/membrane_f2.jpg&imgrefurl=http://www.nature.com/horizon/livingfrontier/background/figs/membrane_f2.html&h=515&w=600&sz=79&hl=en&start=7&um=1&usg=__fJH0ICeFurjs53VZDMSYxrEG46Y=&tbnid=av7X0hnWvTQYzM:&tbnh=116&tbnw=135&prev=/images%3Fq%3Dfluid%2Bmosaic%2Bmodel%26um%3D1%26hl%3Den%26sa%3DN
1.) Tissues-cells that form into a blanket like form & help control movement.
Organs- a body part that contains 2 types of cell tissue & doesn't have any bones in it.
Organ systems- multiple organs that work together to perform the same task in our body.
2.) Tight junctions function to form a seal between adjacent cells and also define the apical and basal sides of an epithelial cell.
adhesive junctions
* hold cells in fixed position
* prominent in epithelial tissues
* associated with cytoskeleton
Adherens junctions and desmosome junctions rely on associations between cadherin proteins
Adheriente junctions
* cadherins cross the plasma membrane and are linked to the cytoskeleton by linker proteins (in this respect, they function like the integrins)
* different cell types produce different types of cadherin proteins
* a cadherin protein will interact only with an identical type of cadherin (homophilic binding)
Info found at: http://www.esf.edu/efb/course/efb325/lectures/junctions.htm
Fluid Mosaic Diagram found at: http://www.jdaross.cwc.net/images/cellmem.gif
1.Tissues
Cells group together in the body to form tissues - a collection of similar cells that group together to perform a specialized function. There are 4 primary tissue types in the human body: epithelial tissue, connective tissue, muscle tissue and nerve tissue.
2comunicating junctions: allow direct passage of chemical or electrical signals from cell to cell.adhesive junctio: mechanically attach cells to oneoccluding junctions: function to seal cells together in an epithelial sheet
3.http://web.jjay.cuny.edu/~acarpi/NSC/14-anatomy.htm
1. A tissue is a population of cells differentiated in one direction that are qualified for activities of the same kind. In connective tissues this cell population is complemented by varying amounts of ground substance.
organs are made up of cells and organs are for a certain function
organs systems are a group of organs
http://www.tiho-hannover.de/einricht/anat/lit/mwenth/conntis/bdgw.htm
2. Three types of cell junctions
* occluding junctions- function to seal cells together and in a epithelial sheet.
*adhesive junctions- it is a mechanically attach cells to one another or to the ecm
* communiticating junctions- it allows a passage of a chemical electrical signals from cell to cell
http://www.esf.edu/efb/course/efb325/lectures/junctions.htm
TISSUE-any of the distinct types of material of which animals or plants are made, consisting of specialized cells and their products.
ORGANS-a part of an organism that is typically self-contained and has a specific vital function, such as the heart or liver in humans.
ORGAN SYSTEM-The human body is made up of several organ systems that work together as one unit.
I USED THE DICTIONARY AS A SOURCE.
Three types of cell junctions are:
* occluding junctions: function to seal cells together in an epithelial sheet
* adhesive junctions: mechanically attach cells to one another or to the ECM
* communicating junctions: allow direct passage of chemical or electrical signals from cell to cell
Found at http://www.esf.edu/efb/course/efb325/lectures/junction
1. A tissue is made out of a group of similar cells. So muscle tissue is made out of muscle cells together. An organ is made out of various tissues that work together to perform a task. So a stomach is an organ that contains muscle tissue, nerve tissue, epithelial tissue, connective tissue, and so on.An organ system is a group of organs that work together to perform a task for the body. The digestive system is an example of a system which is made of the organs: esophagus, stomach, small intestine, and so on.
http://www.answers.yahoo.com
2.The three types of cell junction are the tight junction, adherens junction, and the gap junction. The tight junction provides a sealed barrier, the adherens junction binds together micro-filaments between adjacent cells, and the gap junction allows passage of ions and small molecules between adjacent cells.
3.http://www.hillstrath.on.ca/moffatt/bio3a/cellbio/phase1.htm
Tissue is a cellular organizational level intermediate between cells and a complete organism. Hence, a tissue is an ensemble of cells, not necessarily identical, but from the same origin, that together carry out a specific function. Organs are then formed by the functional grouping together of multiple tissues.In biology, a system is a group of organs that work together to perform a certain task.
http://en.wikipedia.org/wiki/Organ_systems
three major types of cell junctions:
Adherens junctions- three major types of cell junctions:are protein complexes that occur at cell-cell junctions in epithelial tissues, usually more basal than tight junctions.
Gap junctions-A gap junction or nexus is a junction between certain animal cell-types that allows different molecules and ions, mostly small intracellular signaling molecules (intracellular mediators), to pass freely between cells.
Tight junctions-Tight junctions, or zonula occludens, are the closely associated areas of two cells whose membranes join together forming a virtual impermeable barrier to fluid
www.wikipedia.org/wiki/cell_junctions
1. Cells group together in the body to form tissues - a collection of similar cells that group together to perform a specialized function. There are 4 primary tissue types in the human body: epithelial tissue, connective tissue, muscle tissue and nerve tissue. Organs are the next level of organization in the body. An organ is a structure that contains at least two different types of tissue functioning together for a common purpose.Organ systems are composed of two or more different organs that work together to provide a common function. so altogether these three things are pretty similar but if u can tell that there are tiny differences in them.http://web.jjay.cuny.edu/~acarpi/NSC/14-anatomy.htm
2. OCCLUDING JUNCTIONS: function to seal cells together in an epithelial sheet ADHESIVE JUNCTIONS: mechanically attach cells to one another or to the ECM. COMUNICATING JUNCTIONS: allow direct passage of chemical or electrical signals from cell to cell.
3.http://www.harlem-school.com/10TH/sci_pdf/graphics/fluid_mosaic.gif
1. http://web.jjay.cuny.edu/~acarpi/NSC/14-anatomy.htm
"Tissues
Cells group together in the body to form tissues - a collection of similar cells that group together to perform a specialized function."
"Organs
Organs are the next level of organization in the body. An organ is a structure that contains at least two different types of tissue functioning together for a common purpose."
"Organ Systems
Organ systems are composed of two or more different organs that work together to provide a common function."
2. TIGHT JUNCTION- provides a sealed barrier (for organs such as the stomach that needs to keep things in and other things from leaking out)
ANCHORING JUNCTIONS-
•Adherens junction- binds together microfiliments between adjacent cells
•Demosome junction- binds intermediate filaments of adjacent cells
•Hemidemosome- attaches intermediate filaments of the cell to the base membrane
GAP JUNCTION- allows passage of ions and small molecules between adjacent cells
3.http://www.jdaross.cwc.net/images/cellmem.gif
1.Tissues
Cells group together in the body to form tissues - a collection of similar cells that group together to perform a specialized function. There are 4 primary tissue types in the human body: epithelial tissue, connective tissue, muscle tissue and nerve tissue.
1. Epithelial Tissue - The cells of epithelial tissue pack tightly together and form continuous sheets that serve as linings in different parts of the body. Epithelial tissue serve as membranes lining organs and helping to keep the body's organs separate, in place and protected. Some examples of epithelial tissue are the outer layer of the skin, the inside of the mouth and stomach, and the tissue surrounding the body's organs.
2. Connective Tissue - There are many types of connective tissue in the body. Generally speaking, connective tissue adds support and structure to the body. Most types of connective tissue contain fibrous strands of the protein collagen that add strength to connective tissue. Some examples of connective tissue include the inner layers of skin, tendons, ligaments, cartilage, bone and fat tissue. In addition to these more recognizable forms of connective tissue, blood is also considered a form of connective tissue.
3. Muscle Tissue - Muscle tissue is a specialized tissue that can contract. Muscle tissue contains the specialized proteins actin and myosin that slide past one another and allow movement. Examples of muscle tissue are contained in the muscles throughout your body.
4. Nerve Tissue - Nerve tissue contains two types of cells: neurons and glial cells. Nerve tissue has the ability to generate and conduct electrical signals in the body. These electrical messages are managed by nerve tissue in the brain and transmitted down the spinal cord to the body.
Organs
Organs are the next level of organization in the body. An organ is a structure that contains at least two different types of tissue functioning together for a common purpose. There are many different organs in the body: the liver, kidneys, heart, even your skin is an organ. In fact, the skin is the largest organ in the human body and provides us with an excellent example for explanation purposes. The skin is composed of three layers: the epidermis, dermis and subcutaneous layer. The epidermis is the outermost layer of skin. It consists of epithelial tissue in which the cells are tightly packed together providing a barrier between the inside of the body and the outside world. Below the epidermis lies a layer of connective tissue called the dermis. In addition to providing support for the skin, the dermis has many other purposes. The dermis contains blood vessels that nourish skin cells. It contains nerve tissue that provides feeling in the skin. And it contains muscle tissue that is responsible for giving you 'goosebumps' when you get cold or frightened. The subcutaneous layer is beneath the dermis and consists mainly of a type of connective tissue called adipose tissue. Adipose tissue is more commonly known as fat and it helps cushion the skin and provide protection from cold temperatures.
Organ Systems
Organ systems are composed of two or more different organs that work together to provide a common function. There are 10 major organ systems in the human body, they are the:
www.basicanatomy.com
2.In the process of building a multicellular organism, cells are attached to each other in specific ways in the process of building tissues and organs. The organization of cells into "sheets" is also very important in the process of vertebrate development. Through development and also as tissues are maintained in a mature organism, cells express informational and junction molecules on their surface, so that cells recognize and adhere to like cells. In this lecture, we will explore the molecules involved in forming cell-cell adhesion and mechanical junctions.
Cell-cell junctions can be classified into three functional types
* occluding junctions: function to seal cells together in an epithelial sheet
* adhesive junctions: mechanically attach cells to one another or to the ECM
* communicating junctions: allow direct passage of chemical or electrical signals from cell to cell
Occluding junctions
Tight junctions function to form a seal between adjacent cells and also define the apical and basal sides of an epithelial cell
* direct connections between PMs of adjacent cells formed by membrane proteins (claudins and occludins)
* especially important in intestine, bladder, glands
* tight junction segregates active and passive glucose transporters for directional glucose uptake from the lumen of the gut (see Figure 12-15 on page 400)
Adhesive junctions
* hold cells in fixed position
* prominent in epithelial tissues
* associated with cytoskeleton
Adherens junctions and desmosome junctions rely on associations between cadherin proteins
* cadherins cross the plasma membrane and are linked to the cytoskeleton by linker proteins (in this respect, they function like the integrins)
* different cell types produce different types of cadherin proteins
* a cadherin protein will interact only with an identical type of cadherin (homophilic binding)
Adherens junctions join actin bundles in one cell to actin bundles in an adjoining cell
* cadherins linked to actin microfilaments extend out of the cell and bind to cadherins of an adjoining cell
* adherens junctions are often in a continuous belt around the cell=adhesion belt
* can also be in a bundle
* found in heart and thin cell layers covering organs or lining cavities
* the actin microfilaments can contract, thus adherens junctions can be involved in coordinating invaginations during development
www.cell-celljunctions.com
3.Life as we know it is cellular. Small quantities of cytoplasm are bound in sacs of plasma membrane. One of the tasks of cell biology has been to figure out how these remarkable membranes work.
We know that membranes have certain properties.
1. They act as a barrier between the cell and its environment, allowing a complex organized system to exist inside the cell.
2. They permit the passage of selected substances into and out of the cell.
3. They flex, bend and flow to allow the cell to change shape.
As we have accumulated evidence about the cell membrane, biologists have tried to develop models to explain how the boundaries of cells are constructed, and how they function.
The earliest models of the membrane were very simple. Evidence from experiments with cells late in the 19th century suggested that lipid soluble substances entered cells faster than water soluble substances (a fact very important both to the study of poisons and to the development of drugs). The first model of membranes simply suggested that they were layers of lipid (fat). These early models did not account for how a lipid layer could remain stable in contact with the water of the cell and the environment, since lipids are repelled by water. Presumably, the lipids would all have to be bonded together to maintain their integrity, but that would have seriously restricted the flexibility of membranes.
Chemical analyses of isolated membranes in the early twentieth century revealed that they were largely made of phospholipids and cholesterol. It was known that phospholipids were amphiphilic - i.e. they had one end (the head) that was water soluble and two "tails" that were lipid soluble. Experimentally, phospholipids could be made to form a double layer of molecules in water, with the water soluble heads of each layer oriented outward toward the water and the lipid soluble tails oriented inward toward each other. This bilayer would then be stable.
www.hillstrap.com
http://www.harlem-school.com/10TH/sci_pdf/graphics/fluid_mosaic.gif
1. a group of the same cell makes a tissue and a group of different tissues makes up a organ!
http://answers.yahoo.com/question/index?qid=20070916024500AA4nSlC
2. The three types of cell junctions are the tight junction, the adherens junction, and the gap junction. The tight junction provides a sealed barrier between the cells. The Adherens junction bind together micro-fillaments between cells. The gap junction allows ions and small molecules to pass between cells.
3. http://faculty.southwest.tn.edu/rburkett/GB1-os10.jpg
1. Tissues are a group of cells that work together to make a certain function. Tissues make up organs. Organs are the basic body parts that you are not able to live without such as you kidneys, liver, stomach, bladder, etc... The organ systems are the groups of organs that all work together to keep us alive, the systems are the circulatory system, the respiratory system, and the digestion.
2. The three types of cell junctions are tight junction, anchoring junction, and the gap junction. The tight junctions are found mostly in tissues of cells that form the linings of organs, such as the stomach, where tight, sealed barriers are needed. Anchoring junctions mechanically attach the cytoskeleton of one cell to the cytoskeleton of another. The Gap junction provides a narrow passageway between cells that allows small molecules and ions to move directly from the cytoplasm of one cell to the other.
3. http://www.uic.edu/classes/bios/bios100/lectf03am/fluidmos.jpg
tissues- is cells that group together in the body to form tissues
organs- is a structure that contains at least two or more different types of tissue functioning together for a common purpose.
Organ systems are composed of two or more different organs that work together to provide a common function. i found this facts in
http://web.jjay.cuny.edu/~acarpi/NSC/14-anatomy.htm
2.the three types of cell junction are:
* Adherens junctions-are protein complexes that occur at cell-cell junctions in epithelial tissues
* Gap junctions-is a junction between certain animal cell-types that allows different molecules and ions
* Tight junctions-are the closely associated areas of two cells whose membranes join together forming a virtual impermeable barrier to fluid.
3.you can find an example of the fluid mosaic diagram at this website faculty.southwest.tn.edu/rburkett/GB1-os10.jpg
1. Tissue- is a cellular organizational level intermediate between cells and a complete organism.
Organs- is a group of tissues that perform a specific function or group of functions.
organ systems- Organ systems are composed of two or more different organs that work together to provide a common function.
2. Desmosome, tight junction, and gap junction.
3. http://fajerpc.magnet.fsu.edu/Education/2010/Lectures/11_Membranes_files/image024.jpg
Organs are made up of bunches of tissues and tissues are made up of cells and organ systems is a group of organs.In biology, a system is a group of organs that work together to perform a certain task. Common systems, such as those present in mammals and other animals, seen in human anatomy, are those such as the circulatory system, the respiratory system, the nervous system,
three types of cell junctions is
*tight junctions-provides sealed barrier
*Adherens junction-binds together microfilments between adjacent cells
*Gap junction-allows passage of ions and small molecules between adjacent cells.
1.Tissue is a cellular organizational level intermediate between cells and a complete organism. Hence, a tissue is an ensemble of cells, not necessarily identical, but from the same origin, that together carry out a specific function.
An organ is a group of tissues that perform a specific function or group of functions. Usually there is a main tissue and sporadic tissues. The main tissue is the one that is unique for the specific organ. For example, main tissue in the heart is the myocardium, while sporadic are the nerves, blood, connective etc.
Organ systems are composed of two or more different organs that work together to provide a common function.
2.The three types of cell junctions are
A.Gap junctions are between adjacent cells that allow passage of small molecules and facilitate cell-cell communication.
B.Tight junctions function to form a seal between adjacent cells and also define the apical and basal sides of an epithelial cell.
C.Anchoring junctions mechanically attach cells(and their cytoskeletons)to their neighbors or the extracellular matrix.
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