...after a few divisions. The outer layer of cells forms the placenta, whereas the inner mass of cells develops into an embryo The inner cells can differentiate into any part of the new embryo, but it cannot now form part of the placenta. They are pluripotent stem cells. As the embryo develops, some cells differentiate fully and therefore no longer are classed as stem cells, but are classed as specialized body or somatic, cells. Other develops into more specific forms of stem cells, which are multipotent stem cells. Multipotent cells lie dormant in the body’s tissues throughout adult life. These are now known as adult stem cells. For example, haematopoietic cells in bone marrow divide to replace lost or damaged blood cells. The tree types of stem cells are: 1. Embryonic Stem Cells: these include those which are found within the embryo, the foetus or the umbilical cord blood. Embryonic stem cells can give rise to about any cell in the human body; however this depends on when they were harvested. 2. Adult Stem Cells: these can be found in infants, children and adults. They exist in tissue that has already developed such as those in the heart, kidney and the brain. 3. Induced Pluripotent Stem Cells...
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...Unit 5 Anatomy and physiology Functions of the component of the human cell.( http://www.slideshare.net/kristenaoconnor/cell-organelles) Cell membrane: the cell membrane also known as plasma membrane is the biological membrane that separates the interior cell from the outside environment. It provide support and protection for the cell. It serves as the entrance and exit of the cell. Cytoplasm: cytoplasm is a jelly like material that fill the cell. It contains food and water for the cell. It holds the organelle in place. It is mainly composed of water, salt and proteins. Nucleus : it contains the majority of genetic materials as DNA molecules along with variety of protein to form chromosomes. which makes humans who and what they are. Endoplasmic reticulum: the endoplasmic reticulum serves many functions, it folds protein molecules in sacs cisternae, it transports synthesized proteins in the vesicles to the Golgi apparatus. Golgi apparatus: it is made up of membrane bound sacs .The function of the Golgi apparatus is to process and bundle macromolecules like protein and lipids as they synthesize in the cell. It modifies sorts and package proteins to be secreted. Mitochondria: it is of the referred to as the powerhouse . It breaks down food and release energy to the cell. Lysosomes: they organelle that contain the digestive enzymes. It cleans up the cell’s waste product. Centriole: the main function of the centriole is to help the division in cells. It also helps in...
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...-the cells of the body can be divided into 3 groups on the basis of their regenerative capacity- they respond differently to stress and injury 1.- Labile cell ( intermitotic) 2.- Stable cell ( reversible postmitotic ) 3.- Permanent cell ( irreversible postmitotic) The cell cycle and types of cells Proliferating cells occupy several functional states between two mitoses. The cell cycle consists of G1 gap (presynthetic), S (DNA synthesis), G2 gap (premitotic) and M (mitotic ) phases. The cells may leave cell cycle during G1 and then they either cease proliferation, differentiate or eventually die or they enter G0 phase, resting phase from which they can be eventually recruited back to the cycle. G0 phase is a non-proliferative and is known as growth arrest 1.- Labile cells- continuously dividing cells- they continue to proliferate, remain all the time in cell cycle -tissues that contain most labile cells include- -epithelia such as -stratified squamous epithelium of the skin, oral cavity, vagina cervix, esophagus, -lining epithelial cell of the gland such as salivary glands, pancreas biliary tract, -columnar epithelium of uterus, fallopian tube, -urinary epithelium -lymphoid tissue, hematopoetic tissue 2.-Stable cells- quiescent- they are...
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...Chapter 4: Tissues © 2013 John Wiley & Sons, Inc. All rights reserved. Tissues ■ ■ ■ ■ ■ ■ ■ ■ Types of tissues Epithelial tissue Connective tissue Membranes Muscular tissue Nervous tissue Tissue repair: restoring homeostasis Aging and tissues © 2013 John Wiley & Sons, Inc. All rights reserved. Types of Tissues ❑ A tissue is a group of similar cells that usually has a similar embryological origin and is specialized for a particular function. The various tissues of the body are classified into four basic types: epithelial tissue, connective tissue, muscular tissue, and nervous tissue. Epithelial tissue (eṕ -i-THĒ-lē-al) covers body surfaces; lines body cavities, hollow organs, and ducts (tubes); and forms glands. Connective tissue protects and supports the body and its organs, binds organs together, stores energy reserves as fat, and provides immunity. Muscular tissue generates the physical force needed to make body structures move. Nervous tissue detects changes inside and outside the body and initiates and transmits nerve impulses (action potentials) that coordinate body activities to help maintain homeostasis. ❑ 1. 2. 3. 4. © 2013 John Wiley & Sons, Inc. All rights reserved. Epithelial Tissue © 2013 John Wiley & Sons, Inc. All rights reserved. Epithelial Tissue © 2013 John Wiley & Sons, Inc. All rights reserved. Epithelial Tissue © 2013 John Wiley & Sons, Inc. All rights reserved. Epithelial Tissue © 2013 John Wiley...
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...Cells, Tissues and Body Systems P2 Nervous Tissue A number of components make up the nervous system and these are also composed of the nervous tissue. The nervous tissue performs an imperative part in the fact that it is in charge for accepting, distributing and handling sensory input. It can be found in the three main areas of the nervous system which are the brain, nerves and the spinal cord. The nervous system contains two significant parts which are defined as peripheral and central. The peripheral nervous system (PNS) includes the nerves that spread to all ends of the body and the central nervous system (CNS) consists of the spinal cord and the brain where it acts as the fundamental processing interior for all stimuli. Neurons are the specialised basic elements that work inside the nervous tissue. The functional and structural organisation of neurons can be described by elements such as an axon. This transmits information to different neurons, muscles and glands and is usually made from a nerve fibre which is a single process expanding from the cell body of a neuron and carrying nerve impulses away from it. Dendrites carry nerve impulses from adjacent neurons into the cell body and are one of the shorter branching processes of the cell body of a neuron. A motor neuron transmits electrical signals for communication within the body from the central nervous system to the brain and the spinal cord, to muscles and glands elsewhere in the body. The synapse causes...
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...Outline the structure of the main tissue of the body. Epithelium is one of the four basic types of animal tissue. Epithelial tissues line the cavities and surfaces of blood vessels and organs throughout the body. There are four simple principal shapes of epithelial which are cuboidal, columnar, squamous and ciliated. Also there are two compound which are simple and keratinised. Simple cuboidal: Simple cuboidal epithelium is one layer thick. Simple cuboidal tissue joined very tightly together to form a sheet. Each cell is shaped like a cube. It is as wide as it is tall and appears square in cross-section. The nucleus is located in the centre. Simple cuboidal is located in kidney tubules, in ducts and secretory portions of small glands. The function of the tissue is secretes and absorb these locations. Simple columnar: Simple columnar is one layer thick and have column-shaped and have a height of at four times their width. Simple columnar the lining of the stomach and intestines...
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... “listen” to music, but a lot of us seldom actively “smell” things in our daily life. The nose is small, but the generation of sense of smell is too complex to be fully understood still. Main body There are a myriad of differentiated cells responsible for the generation of smell situated in the nasal cavity which constitute part of the olfactory system. Inside the nasal cavity, the turbinates direct the inspired air toward the olfactory epithelium in the upper posterior region, the surface of which is covered by a mucus layer. Though only a few centimeters wide, there are an estimated 6,000,000 bipolar olfactory receptor cells (or neurons) inside the olfactory epithelium. There are about 347 related and various olfactory receptor types and a typical receptor cell contains only one type. Astonishingly, one cell is responsible for a range of odorants, the reason for which will be discussed in the later part. The olfactory cells step into the olfactory mucus with 10-30 receptor bearing cilia, and extend a long axon through the epithelium and cribriform plate to the olfactory bulb, a signal relay center. For detection, odorants, essentially volatile and non-reacting chemicals, have to pass through the 10–40μm thick mucus layer, which is achieved by either diffusion or the aid of odorant binding proteins which escort lipophilic molecules through the aqueous mucus medium. Note that the mucus, mainly secreted by Bowman’s glands, contains a number of enzymes which can kill bacteria...
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...that occur in the process of creating every tissue and organ in the human body. This includes the following processes: 1. The proliferation - increasing the number of cells that occurs as a result of a number of asymmetric cell division by division (when the mother of one daughter cells are formed identical to the mother cell and daughter cell that directs the differentiation); 2. Growth - weight gain and the size of the formed tissue, organ, or whole organism, which occurs as a result of proliferation, ie. creating a large number of cells and the formation of a large amount of extracellular matrix; 3. Determination - predestination cells to be under the influence of inductive factors differentiate into specific cell types (in the body there are about 200 types of cell phenotype). Determination is a restriction...
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...Chapter 4 Learning outcomes 4-1 Identify the four major types of tissues in the body and describe their roles. The four major types of tissues are epithelial, connective, muscle, and neural tissue. The functions of each are that the epithelial tissue covers exposed surfaces, lines internal passageways, and chambers, and forms glands. The connective tissue fills internal spaces, provides structural support for other tissues, transports materials within the body and stores energy. The muscle tissue includes the skeletal muscles of the body, the muscle of the heart, and the muscular walls of hollo organs, The neural tissue carries information from one part of the body to another in the form of electrical impulses. 4-2 Discuss the types and functions of epithelial tissue. The types of epithelial tissue include epithelia and glands. Epithelial provides four important functions that include physical protection, controls permeability, provides sensation, and produces specialized secretions. 4-3 Describe the relationship between structural and function for each type of epithelium. There are columnar, cuboidal, and squamous, which are flattened and scale-like cells. Basically columnar are much higher than they are wide, cuboidal look like squares, and squamous are flat like turtles and therefore not very tall at all. The relationship between each other is that squamous cells provide physical protection and performs absorption and secretion. The cuboidal structure relationship...
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...diverse tasks to keep our body’s functioning. Chemical level– is the simplest level within the structural hierarchy. The chemical level includes the tiniest building blocks of matter, atoms, which combine to form molecules, like water. In turn, molecules combine to form organelles, the internal organs of a cell. Cellular level – the cellular level is made up of the smallest unit of living matter, the cell. The individual cells may have some common functions but vary widely in size and shape. Each type of cell carries out a set of unique tasks within the human body. Tissue level – tissues are groups of similar cells that have a common function. A tissue must contain two different types of cells. The four basic tissue types in humans include epithelium, connective, muscle and nervous tissue. Each tissue has a characteristic role that is vital in the complete function of the human body. Organ level – an organ is a structure composed of at least two different tissue types that perform a specific function within the body. Examples of this include the brain, stomach and liver. Complex functions begin to emerge at this level. Organ system level – one of more organs work in unison to accomplish a common purpose, for instance, the heart and blood vessels work together and circulate blood throughout the body to provide oxygen and nutrients to cells. Besides the cardiovascular system, the other organ systems of the body are the integumentary, skeletal, nervous, muscular,...
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...Chapter.20 Lymphatic System & lymphoid organs and tissues Lymphatic System: returns fluids that have leaked from the blood vascular system back into the blood 3 Parts: Network of lymphatic vessels Lymph = fluid contained in those vessels Lymph nodes - cleanse the lymph as it passes through them Lymphatic vessels form a one way system in which lymph fluid flows only towards the heart. when fluid pressure is greater then the pressure n the lymphatic capillary it will be drained toward the heart. order questions? how does it flow from the lymphatic capillaries to the heart? or opposite way around. The cistern chill collects lymph from the 2 larger lumbar trunks that drain the lower limbs & form the intestinal trunk that drains the digestive organs. Lymphoid Organs & Tissues: provide the structural basis of the immune system -House phagocytic cells & lymphocytes which play roles in the body defines mechanisms & resistance to disease. Ex- Spleen Lymphatic Capillaries: Weave btwn the tissue cells and blood capillaries in the loose CT of the body these vessels to be EXTREMELY permeable due to mini-valves. Lymphatic Trunks: drain large areas of the body, named for the regions which they drain lymph Lymphatic Ducts: R Lymphatic Duct -drains lymph from R upper limb & right side of head and thorax 2) Thoracic Duct much larger b/c receives lymph from the rest of the body Lymph Transport: Lymphatic vessels are low-pressure conduits...
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...Excretory System 1) Respiration(CO2 2) Digestive System 3) Kidney 4) Skin(Sweat, Sebum Kidney • Elimination of waste product of body • Maintain body volume and composition of body fluids • Kidneys are paired situated in lumbosaccral region • Covered by peritoneal • Shape o Mostly it is bean shaped o Cattle it is lobulated o Horse it is heart shaped Urinary System • Kidneys • Ureters • Urinary Bladder • Urethra • Epithelial cells are transitional Muscle of bladder is known as Detruser Muscle Kidney contains 3 main parts • Cortex • Medulla o Outer medulla • Pelvis Types of Nephrons 1) Cortical a. Nephron in cortex but portion is also medullary is known as cortical. 2) Juxta Medullary Nephron has 2 parts 1) Bowmans Capsule 2) Tubular system # of Nephrons in each species |CATTLE |40 LACK | |PIG |12.5 LACK | |HUMAN |10 LACK | |DOG |4.15 LACK | |CAT |1.9 LACK | Note Diagram Tubular System 1) Renal Tubule 2) Loop of Henli a. Descending Lymph b. Thin segment of Ascending Lymph c. Thick segment of Ascending Lymph 3) Collecting Tubule form Collecting Duct 4) Capillary unit work around the structure is known as peritubular...
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...Thesis Statement Writing Tuesday, Jun. 8th 2010 Before you familiarize yourself with thesis statement writing, you need to know what the statement is in the first place. This sentence basically sums up your main objective for writing the term paper, creates a simple guide for the reader and provides the basis for your argument. All in all thesis statement writing is quite simple, as long as you keep some tips and techniques in mind. The first thing you need to do is put together one question which is only possible if you compress the entire thesis. A great way to do this is examine the main topic and create a question out of it. It will give you a basic idea of what the statement should look like and how you should answer that question. The first sentence should introduce the topic and the objective and the next few should spell out how you plan to support your argument. Thesis statement writing, therefore, is about asking yourself the fundamental question that forms the essence of your paper. When you are done writing the statement, step back and examine in from another point of view to determine whether it is strong or weak. A strong statement is one which sparkles with confidence and focuses on one and only one aspect of the issue. This means that you can’t be vague or off-hand about the topic. If you have selected a theme, you should be ready to stand up for it- now is not the time to be diplomatic or meek. In addition to that, it should also spell out the basis for...
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...and examine the effect of substrate concentration on catalase activity. Introduction All chemical reactions require a catalyst. A type of catalyst that exists is an enzyme, which acts to bring out a specific biochemical reaction. At all times, all work inside a cell is being performed by enzymes (Brian, 2000). The purpose of an enzyme is to help the cell carry out reactions very quickly. An interaction must be made for a reaction to become catalyzed. The active site is where this interaction between the enzyme and the reactant and/or reactants takes place. In order for the enzyme to work efficiently and properly, the reactant (or substrate) must position itself perfectly within the active site. Most enzymes usually only can catalyze a single chemical reaction, which is called specificity (Introduction To Enzymes, n.d.). Enzymes can also operate to an optimal extent where chemical reactions can occur rapidly and with the upmost efficiency, under certain conditions known as the enzyme’s optimum activity (Boli, 2012). The many different conditions include environmental, such as pH and temperature, or concentrations of the substrates and enzymes. In this experiment, we examined a substance called catalase. Catalase is the isolated cells from potatoes and beef liver. As the substrate for the experiment, hydrogen peroxide was used at various different amounts. The goal of the experiment was to see if the concentration of the substrate played a role in the amount of enzyme activity...
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...regardless of the presence or absence of metastases.(1) Epidemiology: There was only 104 reported cases of ameloblastic carcinoma (all types) between 1984 and 2009.(1) A number of authors have performed literature reviews pertaining the secondary type, yielding significantly varying aggregates, reflecting the inconsistency and paucity in classification. Compared to the primary ameloblastic carcinoma which arises de novo,...
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