The Influence of Light on Chloroplast Development and Movement
Light is an important regulator of both chloroplast development and
chloroplast movement in plants. In terms of chloroplast development,
light regulates the biogenesis of the photosynthetic apparatus in
chloroplasts and the adaptation of that apparatus to the environment
so as to maximise photosynthesis. In terms of chloroplast movement,
weak light induces chloroplasts to undergo accumulation movement,
while strong light induces avoidance movement. In this way,
chloroplasts are able to move within cells to positions where they can
obtain higher efficiency of photosynthesis while avoiding
photo-damage. In this essay, I will review the role that light plays
in the regulation of both chloroplast development and chloroplast
movement.
(1) Chloroplast development
(a) The development of chloroplasts from proplastids is regulated by
light
Meristematic cells in the shoot and root apices and leaf primordia
contain low numbers of small, undifferentiated proplastids. The
ultrastructure of these non-green proplastids is simple and consists
of the envelope, often with some invaginations from the inner
membrane, and a stroma with some ribosomes, nucleoids, plastoglobuli,
sometimes some inner membranes, and a limited amount of prokaryotic
type DNA [1].
In those tissues and organs destined to become green and
photosynthesising in light, the proplastids develop into etioplasts in
darkness. Etioplasts are the end product of a differential route in
dark-grown angiosperm seedlings that begins with the proplastid stage.
A characteristic feature of the etioplast is the ...
... middle of paper ...
...ight) by modulating the
composition of their photosynthetic membranes to enhance
photosynthesis.
Chloroplast movement is also regulated by (mainly blue) light. Under
weak light conditions, chloroplasts undergo accumulation movement
whereby they move into the illuminated area in order to obtain higher
efficiency of photosynthesis. In contrast, under strong light
conditions, chloroplasts undergo avoidance movement whereby they move
away from the illuminated area, therefore avoiding photo-damage.
Response to the light environment is mediated through photoreceptors
(protochlorophyllide, phytochrome, and UV blue light receptors) that
are already present at the earliest stages of development. Activation
of these photoreceptors initiates and continuously regulates the
structure, function, and movement of chloroplasts.
stems of Ivy, one from the part of the garden that is exposed to lots
Investigating the Effect of Light Intensity on Photosynthesis in a Pondweed Aim: To investigate how the rate of photosynthesis changes at different light intensities, with a pondweed. Prediction: I predict that the oxygen bubbles will decrease when the lamp is further away from the measuring cylinder, because light intensity is a factor of photosynthesis. The plant may stop photosynthesising when the pondweed is at the furthest distance from the lamp (8cm). Without light, the plant will stop the photosynthesising process, because, light is a limited factor. However once a particular light intensity is reached the rate of photosynthesis stays constant, even if the light intensity is the greatest.
... in the chloroplasts in some of their cells. Chlorophyll allows the energy in sunlight to drive chemical reactions. Chloroplasts act as energy transducers, converting light energy into chemical energy. So as the plant has more light the chlorophyll inside the chloroplasts can react faster absorbing in more light for food and energy.¡¨ So this shows my prediction was correct for in my experiment and shown in my result table and graph the more light intensity there is on a plant the higher the rate of my photosynthesis will be. My prediction is very close to what I said the results will be so my prediction was correct and has been proven to be correct in my result table, graph and now explained again in my conclusion.
Investigating the Effect of Light Intensity on the Size of a Plantain Leaf Title: To investigate the effect of light intensity on the size of a plantain leaf. Hypothesis: I predict that the size of the plantain leaves would increase as the light intensity decreases. Therefore, plantain leaves found in the shade will have larger surface areas than leaves found in an open area. Theory: Sunlight is an essential factor need to complete the process of photosynthesis.
The Effect of Light on the Organic Plant Elodea Aim: To calculate the rate of photosynthesis from the number of oxygen bubbles produced by the plant. Photosynthesis: The process by which green plants use the sun's energy to build up carbohydrate reserves. Plants make their own organic food such as starch. Plants need Carbon dioxide, water, light and chlorophyll in order to make food; and starch and oxygen are produced. Carbon dioxide and water are the raw materials of photosynthesis.
The Effect of Light Intensity on the Rate of Oxygen Production in a Plant While Photosynthesis is Taking Place
The Effect of Wavelength on Photosynthesis Rate Aim: To be able to To investigate how different wavelengths (colors) of light affect the photosynthetic rate of the synthetic. I will use a pant that is a pond weed called elodea. I will measure the rate of photosynthesis by measuring the amount of o2 given off in bubbles per minute from the elodea. I will do this by placing the Elodea in a test tube with sodium hydrogen. carbonate then I will vary the light wavelength (color) using colored.
To make the test fair I will use the same amount of water and the leaf
This organelle is the site of photosynthesis in plants and other organisms. In the structure, the chloroplasts has a double membrane, the outer membrane has a continuous boundary. This organelle can be found in a vast group of organelles called the plastid, chloroplasts are usually found in many plant cells but never in animal cells. Chloroplasts organelles are large; they are 4-10um long and 2-3um wide. They are very important to plants because chloroplasts are what plants use to create food from sunlight. Chloroplasts are not found in humans.
[IMAGE]Carbon dioxide + water Light Energy glucose + oxygen Chlorophyll [IMAGE]6CO2 + 6H20 Light Energy C6 H12 O6 + 6O 2 Chlorophyll Photosynthesis occurs in the leaves of the plant in the palisade layer. Chlorophyll in the cells in the palisade layer absorb light for photosynthesis. The plant releases the oxygen created in photosynthesis back into the air but it uses or stores the glucose for energy, respiration, growth and repair. The leaves and plants are also specially adapted for photosynthesis in their structure and cell alignment. Preliminary Experiment Apparatus * Piece of Elodea Canadensis * Bulb * Voltmeter * Test tube * Beaker * Box *
The Effect of Light Intensity on the Rate of Photosynthesis in an Aquatic Plant Introduction The input variable I will be investigating is light, as light is just one of the 4 factors required in the green-plant process of photosynthesis. Photosynthesis is the process by which green-plants use sunlight, carbon dioxide, water & chlorophyll to produce their own food source. This process is also affected by the temperature surrounding the plant (the species of plant we experimented with, pond weed, photosynthesised best at around 20 degrees centigrade.) Light, temperature & CO2 are known as limiting factors, and each is as important as the next in photosynthesis. Light is the factor that is linked with chlorophyll, a green pigment stored in chloroplasts found in the palisade cells, in the upper layer of leaves.
Photosynthesis in simpler turns is the ability of a live plant to carry on its chemical process by the use of light energy. Photosynthesis can not take place when there is absolutely no light, instead it stores the light it captures during the day, and uses it when needed. Photosynthesis can take place in land plants and aquarian plants such as algae. There are many factors that influence the ability of a plant to go through photosynthesis, such as light, the color of light and amount of water and or light.
An Experiment to Investigate the Effect of Light Intensity on the Rate of Photosynthesis. Introduction Photosynthetics take place in the chloroplasts of green plant cells. It can produce simple sugars using carbon dioxide and water causing the release of sugar and oxygen. The chemical equation of photosynthesis is: [ IMAGE ] 6CO 2 + 6H20 C 6 H12 O 6 + 6O2 It has been proven many times that plants need light to be able to photosynthesize, so you can say that without light the plant would neither photosynthesize nor survive.
The structure of chlorophyll involves a hydrophobic tail embedded in the thylakoid membrane which repels water and a porphyrin ring which is a ring of four pyrrols (C4H5N) surrounding a metal ion which absorbs the incoming light energy, in the case of chlorophyll the metal ion is magnesium (Mg2+.) The electrons within the porphyrin ring are delocalised so the molecule has the potential to easily and quickly lose and gain electrons making the structure of chlorophyll ideal for photosynthesis. Chlorophyll is the most abundant photosynthetic pigment, absorbing red and blue wavelengths and reflecting green wavelengths, meaning plants containing chlorophyll appear green. There are many types of chlorophyll, including chlorophyll a, b, c1, c2, d and f. Chlorophyll a is present in all photosynthetic organisms and is the most common pigment with the molecular formula C55H72MgN4O5. Chlorophyll b is found in plants with the molecular formula C55H70MgN4O6, it is less abundant than chlorophyll a. Chlorophyll a and b are often found together as they increase the wavelengths of light absorbed. Chlorophyll c1 (C35H30O5N4Mg) and c2 (C35H28O5N4Mg) are found in algae, they are accessory pigments and have a brown colour. Chlorophyll c is able to absorb yellow and green light (500-600nm) that chlorophyll a
Photosynthesis is a process in which plants and other organisms convert the light energy from the sun or any other source into chemical energy that can be released to fuel an organism’s activities. During this reaction, carbon dioxide and water are converted into glucose and oxygen. This process takes place in leaf cells which contain chloroplasts and the reaction requires light energy from the sun, which is absorbed by a green substance called chlorophyll. The plants absorb the water through their roots from the earth and carbon dioxide through their leaves.