We are caught up, as organic beings, in the naturalprocess through which the earth accepts energy from the sun andthen releases it. There has been life on Earth for at least threeand a half billion years, and over this time there has been aclear and constant evolution in the way energy is used. The firstliving things may have obtained energy from organic moleculesthat had accumulated in their environment, but photosyntheticautotrophs, able to capture energy from sunlight, soon evolved,making it possible for life to escape this limited niche. Theexistence of autotrophs made a place for heterotrophs, which useenergy that has already been captured by autotrophs.
It is not clear how photosynthesis got started,although it is a combination of two systems that can be foundsingly in some life forms that still exist. But blue-green algae,which are among the earliest organisms documented in the fossilrecord, already employed the two-stage process that waseventually handed down to green plants. This is a complexsequence of events that has a simple outcome. Carbon dioxide (ofwhich there was an abundance in the earth's early atmosphere)reacts with water through energy from light, fixing carbon andreleasing oxygen, and a portion of the energy remains captive aslong as the carbon and the oxygen remain apart. Plants releasethis energy when and where necessary to conduct their metabolicbusiness (Starr & Taggart, 1987).
Naturally occurring food and fuel contain complex carbon-based molecules, chiefly derived from plant matter that has been formed by photosynthesis. The chemical reaction of these molecules with oxygen releases energy; such reactions provide energy for most animal life and for residential, commercial, and industrial activities.
The result of two light reactions is a total of six oxygen molecules (6 O2) released into the air as byproducts and 12 NADPH2 (24 H) carried over to the dark reaction of photosynthesis....
The energy released by burning fuel or digesting food was once energy from the sun that was captured by plants in the chemical process that forms plant matter (from air and water). (Boundary: The fact that plants capture energy from sunlight is introduced at this grade level, but details of photosynthesis are not.)
Any chemical process involves a change in chemical bonds and the related bond energies and thus in the total chemical binding energy. This change is matched by a difference between the total kinetic energy of the set of reactant molecules before the collision and that of the set of product molecules after the collision (conservation of energy). Some reactions release energy (e.g., burning fuel in the presence of oxygen), and others require energy input (e.g., synthesis of sugars from carbon dioxide and water).
During the process of photosynthesis, carbon dioxide plus water in the presence of sunlight, enzymes and chlorophyll produce glucose and oxygen as waste product.
The occurrence of photosynthesis is very important to us as humans, because it provides us with the oxygen we need to breathe and plants are at the bottom of every food-chain and so without them, I would collapse....
Understanding chemical reactions and the properties of elements is essential not only to the physical sciences but also is foundational knowledge for the life sciences and the earth and space sciences. The cycling of matter and associated transfers of energy in systems, of any scale, depend on physical and chemical processes. The reactivity of hydrogen ions gives rise to many biological and geophysical phenomena. The capacity of carbon atoms to form the backbone of extended molecular structures is essential to the chemistry of life. The carbon cycle involves transfers between carbon in the atmosphere—in the form of carbon dioxide—and carbon in living matter or formerly living matter (including fossil fuels). The proportion of oxygen molecules (i.e., oxygen in the form O2) in the atmosphere also changes in this cycle.
It will be very interesting to see how light will influence the rate of photosynthesis in plants and what will happen if they do not get the required light in order to produce starch .
I believe this will happen because when the light source is nearer to the plant more of the plants surface area is coming in to contact with the light from the desk lamp therefore more photosynthesis will occur which will mean more oxygen will be produced which will create more bubbles....
The existence of atoms, now supported by evidence from modern instruments, was first postulated as a model that could explain both qualitative and quantitative observations about matter (e.g., Brownian motion, ratios of reactants and products in chemical reactions). Matter can be understood in terms of the types of atoms present and the interactions both between and within them. The states (i.e., solid, liquid, gas, or plasma), properties (e.g., hardness, conductivity), and reactions (both physical and chemical) of matter can be described and predicted based on the types, interactions, and motions of the atoms within it. Chemical reactions, which underlie so many observed phenomena in living and nonliving systems alike, conserve the number of atoms of each type but change their arrangement into molecules. Nuclear reactions involve changes in the types of atomic nuclei present and are key to the energy release from the sun and the balance of isotopes in matter.
Like letters of the alphabet that can be rearranged to form new words with very different meanings, atoms move around during chemical reactions, and they form new compounds with vastly different personalities.When we burn sugar (a compound made of the elements hydrogen, oxygen, and carbon) in our bodies, the elements are reorganized into water and carbon dioxide.