Epidermis

Question: How to tell which is upper epidermis and lower epidermis? How do you tell which is the upper and which is the lower epidermis when looking at a microscope drawing of a leaf cross section?

Answer: If the cross section does not include any stomata, the lower epidermis of a dicot is the layer closest to the spongy mesophyll, so you will see large air spaces. The layer next to the upper epidermis has no air spaces and consists of closely packed cigar-shaped cells called the palisade layer. John H

Question: How is the lower epidermis adapted for the function of gas exchange in a leaf? How is the lower epidermis adapted for the function of gas exchange in a leaf? I have it as a biology question and I am so stuck! Many thanks

Answer: The lower epidermis is made out of guard cells and stomata. The guard cells are the cells that form the lower epidermis. The stomata, literally meaning 'mouth', are the openings in the bottom of the leaf. The stomata and their size is regulated by the movements of the guard cells. The CO2, carbon dioxide, needed for photosynthesis enters the stomata and the product O2, oxygen, exits from this opening.

Question: What is the function of the lower epidermis in leaf cells? What are the functions of the upper and lower epidermis in leaves? Thanks!

Answer: There are many stomata perforating the lower surface. Each stomata are surrounded by a set of guard cells that contain chlorophyll. Functions of the Epidermis : The cuticle prevents water loss. The epidermis protects the internal tissues from injury. The stomata allows for gaseous exchange for photosynthesis and respiration. Since the epidermis is translucent it allows light to reach the mesophyll tissue for photosynthesis.

Question: What type of pigment is present in the upper epidermis of the Rhoeo discolor leaf? How about in the lower epidermis?

Answer: Rhoeo discolor of family Commelinaceae is also known by other scientific names as - Tradescantia spathacea and Tradescantia discolor . Click on the link below to see the plant and confirm = http://upload.wikimedia.org/wikipedia/co… http://www.floraexotica.ca/images/Oyster… Question 1 )What type of pigment is present in the upper epidermis of the Rhoeo discolor leaf? Answer 1 ) The cells of the upper epidermis of this plant do not contain any pigment and are transparent . click on the link below to see that epidermis - http://www.lima.ohio-state.edu/biology/i… The tiny dots that you see in every cell are the nuclei of the respective cells that have been colored . The green color of the upper surface is due to the chloroplasts and chlorophyll that is present in the mesophyll cells near the upper epdermis . Click on the link below to see them= http://www.bio.miami.edu/~cmallery/150/c… Question 2 ) How about in the lower epidermis? Answer 2 ) The cells of the lower epidermis of Rhoeo discolor , on the other hand , contain Anthocyanin pigment that is dissolved in the cytoplasm . That is why the leaf surface appears magenta / purple color . click on the link below to see such cells = http://www.botany.hawaii.edu/faculty/Web… http://upload.wikimedia.org/wikipedia/co…

Question: Which 2 strata of the epidermis are most susceptible to cancer? Which 2 strata of the epidermis are most susceptible to cancer? I was thinking Stratum Basale ? and ?

Answer: Stratum basale and spinalis because they are mitotically active.

Question: Why are there chloroplasts in the guard cells of the lower epidermis only and not in the upper epidermis? I am not sure why this occurs and I can't figure it out. Basically why do the guard cells in the lower epidermis have chloroplasts and those in the upper epidermis do not? I think that possibly it could be that since there is more water loss on the upper surface due to direct sunlight, it would be less efficient to have chloroplasts there.

Answer: Chloroplast are present everywhere in the leaves but predominantly in the palisade mesophyll which is a layer of modified parenchyma cells underneath the upper epidermis. They are elongated and stacked closely to each other for efficient photosynthesis as the light penetrates the upper epidermis. The lower spongy mesophyll cells are scattered for gases to be stored there. There are chloroplast in the guard cells but the epidermal cells that are near the stomata have translucent leucoplasts. I think what you are thinking of are the subsidiary cells. Some leaves have them and some don't. They're located near the guard cells and help them with closing and opening and don't have chloroplasts. Most stomata remain on the bottom of leaves because of several reasons. They are shielded from the intense sunlight as well as heat. It is generally cooler and of course shaded on the bottom of the leaves. Stomata regulate gases but they can't filter them which means that when they're opened CO2 can come in and water can come out. The stomata don't want to remain opened too long for fear of loosing water but don't want to remained closed too long because they need CO2. Being on the bottom of leaves allow them to stay open as much as they can without loosing too much water from the heat. Also they're protected from the wind which can cause evaporation of water. In summary chloroplast are everywhere within the leaves. But they're focused on the top especially within the palisade mesophyll layer. This layer is shielded by the upper epidermal layer of cells. They are also located in guard cells.

Question: Where can I find staphylococcus epidermis bacteria? I'm working on a science project for school, and I need staphylococcus epidermis bacteria. Where exactly can I find it, or how can i get it?

Answer: S epidermidis is a normal inhabitant of human skin...

Question: Why do aquatic plants have stomates at the upper epidermis? Why do aquatic plants have stomates at the upper epidermis, while the terrestrial plants have more stomates at the lower epidermis?

Answer: Aquatic plants such as water lily that floats on the surface of water and therefore stomata are not found at the lower epidermis. Stomata are found on the upper epidermis because they allow direct exchange of gases between the leaf and the atmosphere. While the terrestrial plants such as sunflower have more stomata at the lower epidermis because this is an adaption to reduce the excessive loss of water through transpiration, which occurs through the stomata openings when the leaves are spread out to receive maximum amount of sunlight.

Question: What are the ecological and medical significance of bacillus subtillus and staphylococcus epidermis? What are the ecological and medical significance of bacillus subtillus and staphylococcus epidermis?

Answer: Bacillus subtillus: not much medical significance, but is involved in some cases of food poisoning. Ecological significance involves is when it is used as a soil inoculant in horticulture and agriculture. Staphylococcus epidermis: can form a biofilm in catheters, and may cause of infection in patients whose immune system is compromised.

Question: why is the lack of chlorophyll in the lower epidermis important? why is the lack of chlorophyll in the lower epidermis important in allowing the guard cells to function correctly?

Answer: The function of guard cells is based on their turgor. to vary the osmotic pressure, in guard cells starch and soluble sugar are converted: Insoluble starch > low pressure > stomata closed; enzymatic reaction > soluble sugar > water is absorbed from lower epidermis cells > higher pressure > stomata open. If lower epidermis cells would contain chlorophyll as guard cells do, they also would contain sugar and osmotic pressure would hinder the guard cells to suck in water > they are not able to function properly.

Question: Besides the following functions, what other functions may the epidermis have? Knowing that on humans the epidermis is skin. --protects against water loss, regulates gas exchange, secretes metabolic compounds, and (especially in roots) absorbs water and mineral nutrients.

Answer: It also helps regulate body temperature and protect against disease and irritants. I'm a little curious where the roots are on humans, though...

Question: Factors affecting amount of water vapour produced by lower and upper epidermis of leaves? An experiment is carried out to determine the transpiration index of upper and lower epidermis of leaves both in light and dark. What could cause the transpiration index of lower epidermis to be higher than those of upper epidermis besides the number of stomata? And how does the light/ dark condition affect the amount of water vapor produced by plants?

Answer: answer for the first question has been answered.but for the light and dark one, it is due to different rates of photosynthesis and underlying metabolic activity which results in differential stomatal openings.The light effect is also regulated by several signal transduction mechanisms depending on blue as well as red light.

Question: Where on the root would you find the epidermis? What is it’s function? Where on the root would you find the epidermis? What is it’s function?

Answer: The epidermis is a single-layered group of cells that covers plants leaves, flowers, roots and stems. It forms a boundary between the plant and the external world. The epidermis serves several functions, it protects against water loss, regulates gas exchange, secretes metabolic compounds, and (especially in roots) absorbs water and mineral nutrients. basically, it is the outer most layer and it prevents water loss, regulates gas exchange and absorbs water and minerals.

Question: where do you find Staphylococcus epidermis bacteria ? Im doing a project, and I need to use Staphylococcus epidermis bacteria . I'm not sure what it is. Please help!

Answer: The word epidermis means skin. If this stuff isn't found on your skin, i'll eat my shirt.

Question: If a dysplastic mole has not gone into the epidermis, does that mean that it cannot turn into melanoma? My husband had a dysplastic mole removed and the doctor said that, although the mole was dysplatic and the cells were changing in the epidermis, it had not gone into the dermis or any lower. Does this mean we caught it before it has a chance of turning into melanoma?

Answer: if the mole is removed pror to chaqnging into a melanoma and its all removed its clear of cancer regardless of how deep it goes

Question: What is the significance of a coating of cutin on the epidermis of roots, shoot, and leaves? What is the significance of a coating of cutin on the epidermis of roots, shoot, and leaves

Answer: the cuticle is a water-impervious protective layer covering the epidermal cells of leaves and other parts and limiting water loss. It consists of cutin, a waxy, water-repellent substance allied to suberin, which is found in the cell walls of corky tissue.

Question: What is the structural component of epidermis of Human skin? I heard Cellulose is the structural component of the primary cell wall of green plants, many forms of algae and the emcees. Would you tell me what is the structural component of epidermis of Human skin? ---- is that melanin ??????? :-\

Answer: melanin is incorrect since it serves the function as to give the COLOURING of the skin The correct term would be keratin ^_^ The epidermal cells have 90% keratinocytes that produce keratin. Its function is tobe waterproof, and skin protection from microbes and heat ^_^

Question: What should I do if the first layer of my skin (epidermis) fell off my foot? I recently got new football cleats and while I was practicing I felt pain from the ball arch put into the shoe, I thought it was natural since I was breaking in the shoes, but when I checked it the epidermis of my right foots' arch fell off, now the second layer is showing and I don't know what I should do, I looked all over the internet and absolutely nothing. Please help.

Answer: Ouch. Try taping the area with athletic tape until the skin heals. You may need to do this for a week or two but it won't stop you from playing. Keep the tape on, even in the shower.

Question: From which human embryonic layer fo the epidermis of the skin and the nervous system develop? From which human embryonic layer fo the epidermis of the skin and the nervous system develop? 1) Ectoderm 2) Blastula 3) Mesoderm 4) Gastrula Please help!!

Answer: The purpose of gastrulation is to position the three embryonic germ layers, the endoderm, ectoderm and mesoderm. These layers later develop into certain bodily systems. The ectoderm develops into the skin, nails, the epithelium of the nose, mouth and anal canal; the lens of the eye, the retina and the nervous system. The endoderm develops into the inner linings of the digestive tract, as well as the linings of the respiratory passages. It also forms many glands, such as the liver and pancreas. The mesoderm forms the somites, the notochord, and the mesenchyme, which give rise to the muscles, circulatory and excretory systems of the body.

Question: Can you feel your epidermis with your finger? I'd like to know, can anyone feel their epidermis at anytime with their own hand. Thank you.

Answer: I love feeling my epidermis - it's quite stimulating.