Page
  1. 1
    1
  2. 2
    2

Comparison between photosynthesis and respiration

Extracts from this essay...

Introduction

Comparison between photosynthesis and respiration Photosynthesis and respiration are both processes that are necessary for the survival of organisms. However, in many ways these two processes are very different as they are responsible for contrasting necessities. Therefore they have both similarities and differences. One major difference between the two is that photosynthesis occurs wholly in plants while respiration occurs in both plants and animals. This is because plants are autotrophic so have to produce their own food while animals are heterotrophic as they obtain food by consuming it in the form of other animals or plants. Plants produce their own food via photosynthesis and as animals do not need to produce their own food they have no need for photosynthesis. Both plants and animals require respiration because it is the process in which food is converted into energy in the form of ATP, which is used for many processes within all organisms.

Middle

Respiration and photosynthesis need coenzymes that can be reduced to carry hydrogen. In photosynthesis the coenzyme present is NADP which becomes reduced NADP when it accepts a hydrogen. This is used to oxidise glycerate 3-phosphate into triose phosphate which then proceeds to become glucose and then starch. In respiration two such enzymes are used; NAD and FAD. All of these coenzymes are used to transport hydrogen to where it is needed in the process. A basic difference between the two is the actual reactants and products formed. In respiration the reactants are oxygen and glucose. The oxygen is the final acceptor of the hydrogen atoms in a reaction catalysed by cytochrome oxidase forming water. Oxygen is essential for the whole aerobic process - everything after glycolysis - and if not present will cause a back up through the electron transport chain up to glycolysis. The glucose is used to produce pyruvate which commences the Kreb's cycle.

Conclusion

In photosynthesis there is the light dependent reaction in the thylakoid and the light independent reaction in the stroma. Another similarity in respect to different parts of each process is the actual location of each part. Anaerobic respiration occurs in the cytoplasm and aerobic respiration occurs in the mitochondria. The difference in location mirrors that of photosynthesis although within photosynthesis the whole process takes place within the chloroplasts; anaerobic respiration takes place outside the mitochondria. In conclusion, although respiration and photosynthesis are fundamentally very different processes with regards to purpose and the products and reactants involved they are still strikingly similar in many respects. This is due to the fact that both are essentially organic processes that involve very similar carbon based molecules as well as a number of other molecules such as ATP and the coenzymes. Both processes are ultimately concerned with provided the organism with energy and a source of energy to enable it to carry out other necessary processes.

The above preview is unformatted text

Found what you're looking for?

  • Start learning 29% faster today
  • Over 150,000 essays available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Over 180,000 student essays
  • Every subject and level covered
  • Thousands of essays marked by teachers

Related AS and A Level Energy, Respiration & the Environment

  1. Marked by a teacher

    'An investigation into the ability of two strains of the yeast Saccharomyces cerevisiae to ...

    4 star(s)

    lactose and galactose), the level of wine yeast respiration that was brought about, was less than when no substrate was supplied, as in the control (see table 3 and table 4). This was also the case when the respiration substrate given to baking yeast was galactose.

  2. How ATP is produced in both the chloroplast and mitochondria.

    Figure 1 shows a mitochondrial ETC. It consists of three protein complexes - complex I is the dehydrogenase complex, III the b-c1 complex and IV the cytochrome oxidase complex`. Each contains multiple oxidation-reduction centres. In I the main redox couple is NAD+/NADH, in III it is Fe3+/Fe2+, and in IV it is Cu2+/Cu+.

  1. Explain the basis of ATP generation in mitochondria and chloroplasts. How does this differ ...

    This mechanism was first proposed by Mitchell in 1961, and was called the chemiosmotic hypothesis. The electrochemical gradient that drives ATP synthesis can be produced by the photolysis of water (in chloroplasts only) or by the energetically favourable oxidation of the highly reduced compound NADH (and FADH2).

  2. Investigating how prolonged exposure to its optimum temperature affects the respiration of yeast.

    the following guidelines have to be followed: In order to protect the yeast, the operator will have to ensure that an excess is not used, and that only the necessary amount of yeast is used and no more. This makes sure that it is treated with respect as an organism.

  • Over 180,000 essays
    written by students
  • Annotated by
    experienced teachers
  • Ideas and feedback to write
    your own great essays

Marked by a teacher

This essay has been marked by one of our great teachers. You can read the full teachers notes when you download the essay.

Peer reviewed

This essay has been reviewed by one of our specialist student essay reviewing squad. Read the full review on the essay page.

Peer reviewed

This essay has been reviewed by one of our specialist student essay reviewing squad. Read the full review under the essay preview on this page.