Only the top layer of skin cells are alive. true or false?
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False, only the top layer are dead.
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biologically speaking...an organism is said to be alive if\n1. they  grow\n2. they undergo metabolism\n3.they respond to stimuli\n4.they reproduce\n5.they have an organised cell
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Some cells don't regenerate ever (nerve cells).  Some cells are constantly regenerating (red blood cells).  Red blood cells only have a lifespan of a week.
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No.  Only in plant cells.
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OK dead tissue is gone  but you can skin graft body tissue from one to another as they are living like grafting skin tissue to burned Vitim's living to living!!!!!!!!~~~~~~ dead not~~~~~~\nCOME ON MR. FRANKENSTEIN
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1. Eukaryotes can be multicellular or unicellular.  Prokaryotes (bacteria) are single celled organisms.\n2. Mitochondria and golgi apparatus can be found in skin cells.
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Its definately the skin. C'mon ppl, Biology 101.
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Ermm, the fact that cells are the smallest building blocks of life is the reason that we see things as they are.\n\nThe basis is that all cells contain life and they make what is specified in their DNA/RNA. Heart cells make hearts, lung cells -> lungs, blood cells -> red or white, skin cells -> skin..you get the idea.\n\nI hope I have answered your question, or at least to a certain extent.
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That would be epithelial.
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I know of two kinds of cells that are not regenerated: Brain cells (neurons) and if you are female, eggs cells in the ovary.  The ones you are born with are still with you.
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It's generally considered the skin.  The largest internal organ is the liver.
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Inside the body, the liver.\n\nSome would say in general it's the skin (which is made of several tissues).
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Hello,\n\n-The epithelial tissue or epithelium in dermatology is a tissue composed of a layer of cells. In humans, it is one of four primary body tissues. Epithelium lines both the outside (skin) and the inside cavities and lumen of bodies. The outermost layer of our skin is composed of dead stratified squamous epithelial cells, as are the mucous membranes lining the inside of mouths and body cavities. Other epithelial cells line the insides of the lungs, the gastrointestinal tract, the reproductive and urinary tracts, and make up the exocrine and endocrine glands.\n\nFunctions of epithelial cells include secretion, absorption, protection, transcellular transport, sensation detection, and selective permeability. Endothelium (the inner lining of blood vessels) is a specialized form of epithelium.\n\n\n-Connective tissue: is one of the four types of tissue in traditional classifications (the others being epithelial, muscle, and nervous tissue.) It is largely a category of exclusion rather than one with a precise definition, but all or most tissues in this category are similarly:\nInvolved in structure and support. \nDerived from mesoderm (there are exceptions). \nCharacterized largely by the traits of non-living tissue. \nBlood, cartilage, and bone are usually considered connective tissue, but because they differ so substantially from the other tissues in this class, the phrase "connective tissue proper" is commonly used to exclude those three. There is also variation in the classification of embryonic connective tissues; on this page they will be treated as a third and separate category. Also, labrums, facia, tendons, & ligaments are connective tissues.\n\n\nMuscular tissue: provides for all body movement. Contracting  muscles  cause  body  parts  to  move.  The three types of muscle tissue are skeletal, smooth, and cardiac. Skeletal Muscle  Tissue Skeletal  (voluntary)  muscle  fiber  is  striated,  or striped, and is under the control of the individual's will (fig. 1-9). For this reason, it is often called “voluntary” muscle   tissue.   Skeletal   muscle   tissues   are   usually attached to bones. When muscle fibers are stimulated by an action of a nerve fiber, the fibers contract and relax.  This  interaction  between  muscle  and  nervous fibers produces movement\n\nSmooth Muscle Tissue These  muscle  fibers  are  smooth,  or  nonstriated, and are not under the control of the individual's will . For this reason, this type of muscle tissue is called “involuntary.” Smooth muscle tissue is found in the   walls   of   hollow   organs,   such   as   the   stomach, intestines, blood vessels, and urinary bladder. Smooth muscle  tissues  are  responsible  for  the  movement  of food through the digestive system, constricting blood vessels, and emptying the bladder. \n\nGeneral \nAll living cells have the ability to react to stimuli. Nervous tissue is specialised to react to stimuli and to conduct impulses to various organs in the body which bring about a response to the stimulus. Nerve tissue (as in the brain, spinal cord and peripheral nerves that branch throughout the body) are all made up of specialised nerve cells called neurons. Neurons are easily stimulated and transmit impulses very rapidly. A nerve is made up of many nerve cell fibres (neurons) bound together by connective tissue. A sheath of dense connective tissue, the epineurium surrounds the nerve. This sheath penetrates the nerve to form the perineurium which surrounds bundles of nerve fibres. blood vessels of various sizes can be seen in the epineurium. The endoneurium, which consists of a thin layer of loose connective tissue, surrounds the individual nerve fibres. \n\nAlthough the system forms a unit it can be divided into the following parts: the central nervous system (CNS) which consists of the brain and spinal cord, the nervous system consists of the nerves outside the CNS which connect the brain and spinal cord to the organs and muscl
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All human tissue and body parts are made of cells. They are the building blocks of all living creatures.
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A  Epidermis \n\nThe blade consists of an upper and lower epidermis and a spongy layer of tissue, called the mesophyll. Running through the mesophyll is a branching system of veins.\n\nThe epidermis is the leaf blade's skin. It is a thin, usually transparent, colorless layer of cells that covers both the upper and lower surfaces of the blade. The epidermis prevents the leaf from losing excessive amounts of water and protects it against injury.\n\nIn most plants the epidermis is covered with cutin, a waxy substance secreted by the epidermal cells. The layer of cutin, called the cuticle, is responsible for the glossy appearance of some leaves. The cuticle gives the leaf additional protection by slowing down the rate at which water is lost. Generally, the cuticle is thinner on the epidermis on the underside of the leaf than on the upper epidermis, which is exposed to the sun.\n\nIn many kinds of leaves, hairs grow from the epidermis. The soft hairs of plants such as the mullein give the leaves a woolly or feltlike texture. In some plants the epidermal hairs secrete fluids. For example, in geraniums and petunias the hairs secrete a fluid that gives the leaves a clammy texture. The strong-smelling oils of the peppermint and spearmint plants come from epidermal hairs. In other plants, such as the nettle, the epidermal hairs are stiff and contain a poisonous fluid that produces a skin irritation when a person is pricked by them.\n\nB  Guard Cells \n\nScattered throughout the epidermis are pairs of bean-shaped cells, called guard cells. Guard cells contain chloroplasts, which are tiny granules filled with the green pigment chlorophyll. Chlorophyll gives leaves their characteristic green color. Chloroplasts enable leaves to carry on photosynthesis because they are able to absorb carbon dioxide and sunlight, which are required for the food-making process. In response to heat and light, each pair of guard cells pulls apart, and a tiny pore forms between them. The pores, called stomata, open to the outside atmosphere.\n\nWhen the stomata are open, carbon dioxide and oxygen pass either in or out—when carbon dioxide enters, it takes part in photosynthesis, the food-making process that releases oxygen as a waste product. This oxygen passes out of the leaf. At the same time, oxygen also enters the leaf, where it takes part in respiration, a process that forms carbon dioxide as a waste product. This carbon dioxide passes out through the stomata. Water also passes out of the open stomata in the form of a vapor. This process is called transpiration. Generally, there are more stomata on the under surface of a leaf than on the upper surface. This prevents water from evaporating too quickly or in excessive amounts from the leaf's upper side, which is exposed to the sun. Stomata close at night, providing another level of water conservation.\n\nC  Water Pores \n\nIn addition to the stomata, many kinds of leaves have large specialized water pores in their epidermis. These pores, called hydathodes, permit guttation, the process by which a plant loses liquid water. Unlike the stomata, hydathodes remain open all the time.\n\nGuttation takes place only when water is being rapidly absorbed by the roots, such as after a heavy rainfall, and when transpiration slows down, as on cool, humid nights. When these conditions occur together, droplets of water can be seen on the leaf early in the morning before they evaporate in the heat of the day. Unlike dew, which condenses on leaves from water vapor in the air and covers the entire leaf surface, guttation droplets form only on the edges and tips of leaves. Generally, the droplets are noticeable only on the leaves of strawberries and a few other kinds of plants.\n\nD  Mesophyll \n\nThe mesophyll, sandwiched between the upper and lower epidermis, consists of many thin-walled cells that are usually arranged in two layers. The palisade layer is next to the upper epidermis. It consists of cylindrical cells t
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The skin is composed of two main layers: the outer epidermis and the inner dermis.The epidermis is epithelial tissue and is avascular, meaning that it does not have any blood vessels,therefore no blood supply. However, the dermis which is underneath the epidermis and part of the skin is vascular. It contains blood vessels, therefore blood supply. So, when the cut is superficial and goes only through the epidermis, thee is no bleeding. But if it is a deeper cut reaching the dermis, we will of course bleed because of the presence  of blood vessels in this region of the skin.
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Ok  each cell has its own wall, think of it like a water balloon.  now take a whole bunch of these water balloons and stack them together,  say thats you skin holding all your blood in, ahh but your blood is made up of cells as well.  now when there is a break in the skin blood pours out, why not water? because the water is still contained within each individual cell.  The cells themselves are not broken only pushed apart by whatever is poking you.  that make sense?