Hope it helps Related questions Why does photosynthesis need light? Why is photosynthesis referred to as a biochemical pathway? Why is photosynthesis important for plants?
How does photosynthesis store energy? How do photosystems 1 and 2 differ? How does color affect light absorption? How are pigments related to photosystems? How do chloroplasts and mitochondria work together? What are chloroplasts? What is the visible spectrum? Photosynthesis is essential to all life on earth; both plants and animals depend on it.
It is the only biological process that can capture energy that originates in outer space sunlight and convert it into chemical compounds carbohydrates that every organism uses to power its metabolism.
In brief, the energy of sunlight is captured and used to energize electrons, which are then stored in the covalent bonds of sugar molecules. How long lasting and stable are those covalent bonds? The energy extracted today by the burning of coal and petroleum products represents sunlight energy captured and stored by photosynthesis around million years ago.
Plants, algae, and a group of bacteria called cyanobacteria are the only organisms capable of performing photosynthesis Figure 1. Figure 2. Photoautotrophs including a plants, b algae, and c cyanobacteria synthesize their organic compounds via photosynthesis using sunlight as an energy source.
Cyanobacteria and planktonic algae can grow over enormous areas in water, at times completely covering the surface. H Psilotum whisk fern sporophyte with reduced leaves and spherical synangia three fused sporangia ; magnification x 0. I Equisetum horsetail sporophyte with whorled branches, reduced leaves, and a terminal cone; magnification x 0.
J Cycas seed plant sporophyte showing leaves and terminal cone with seeds; magnification x 0. Origin of land plants.
New York: J. Wiley and Sons, All rights reserved. Part B: courtesy of M. Feist, University of Montpellier. Coleochaete orbicularis. Both the gametophyte and the background are bright green. The gametophyte has an irregular circular shape and a scalloped edge. It is divided into many box-like segments cells , each with a visible, round nucleus inside. Panel b shows a Chara gametophyte. The organism has branching, tendril-like leaves reaching from a primary stalk.
The green leaves are punctuated with small, round, yellow structures. A green liverwort gametophyte, In panel c, is protruding from the soil. Its four primary stems each diverge into two halves and then branch again at their termini, so that each has a forked end. Panel d shows a hornwort gametophyte. Each green stem resembles a single blade of grass.
Panel e shows moss gametophytes with sporophytes protruding from the ground. The gametophytes have small green leaves, and the sporophytes are thin, unbranched, brown stalks. Each sporophyte has a fluorescent orange, oviform capsule called a sporangia perched on top of its stalk. Panel f shows six clubmoss sporophytes emanating from the ground. Some stand vertically out of the soil, and some curve or have fallen horizontally.
They have many stiff, protruding, spine-like, green leaves. The sporangia are small yellow balls at the base of the leaves. Panel g shows fern sporophytes with many stems covered with small, elongated, symmetrical green leaves.
Panel h shows a whisk fern sporophyte with long, straight, green stems beaded with yellow, round synangia along their lengths. In panel i, a horsetail sporophyte is shown. It has a single long stem, which is surrounded by a skirt of green leaves at its base and an elongated, yellow cone at the top.
In Panel j, a large Cycas seed plant sporophyte is shown. Long fronds emanate upwards from the plant's trunk, and in the center of them there is a large mass called the cone. Panel a is a photomicrograph of a gametophyte of a microscopic green alga called Coleochaete orbicularis. Most living things depend on photosynthetic cells to manufacture the complex organic molecules they require as a source of energy.
Photosynthetic cells are quite diverse and include cells found in green plants, phytoplankton, and cyanobacteria. During the process of photosynthesis, cells use carbon dioxide and energy from the Sun to make sugar molecules and oxygen. These sugar molecules are the basis for more complex molecules made by the photosynthetic cell, such as glucose.
Then, via respiration processes, cells use oxygen and glucose to synthesize energy-rich carrier molecules, such as ATP, and carbon dioxide is produced as a waste product. Therefore, the synthesis of glucose and its breakdown by cells are opposing processes. Figure 2 2 in the sky represents the process of photosynthesis. Two arrows are directed outwards from the trees towards the atmosphere. One represents the production of biomass in the trees, and the other represents the production of atmospheric carbon dioxide CO 2.
Arrows emanating from a tree's roots point to two molecular structures: inorganic carbon and organic carbon, which may decompose into inorganic carbon. Inorganic carbon and organic carbon are stored in the soil. This CO2 can return to the atmosphere or enter rivers; alternatively, it can react with soil minerals to form inorganic dissolved carbonates that remain stored in soils or are exported to rivers. B The transformations of organic to inorganic carbon through decomposition and photosynthesis continue in rivers; here, CO2 will re-exchange with the atmosphere degassing or be converted to dissolved carbonates.
These carbonates do not exchange with the atmosphere and are mainly exported to the coastal ocean. Organic carbon is also exported to the ocean or stored in flood plains.
C In the coastal ocean, photosynthesis, decomposition, and re-exchanging of CO2 with the atmosphere still continue.
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