• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

What is a Plant?

Extracts from this document...

Introduction

What is a Plant? MOST PLANTS are green because they contain the substance chlorophyll. They use it to trap light energy; this is used during photosynthesis to make food. Plants are usually anchored in a growing medium such as soil. Some, such as mosses and liverworts, are small and delicate. Others, such as the giant redwood trees, are huge. Many plants, such as marigolds and sunflowers, are annuals, which means that they live for just a year. Perennials can live for many years: some bristlecone pine trees, for example, are nearly 5,000 years old. Rainforest vegetation Where a plant lives depends on its growing requirements. Plants of the rainforest, for example, need its humid climate in order to survive and grow. Flowering Plants FLOWERING plants, known as angiosperms, are the most widespread of all plants. Using flowers to reproduce has contributed to this success. Flowers carry the reproductive organs within a ring of petals. After pollination and fertilization, the flowers produce seeds, which are often enclosed and protected by fruits. There are two classes of flowering plants: monocots, such as grasses, in which the seed embryo has only one leaf; and dicots, such as oak trees, in which the seed embryo has two leaves. Flowering plants use a variety of ingenious ways to scatter their seeds. Non-flowering Plants PLANTS that do not use flowers for reproduction include conifers, ferns, and mosses. ...read more.

Middle

Anaerobic Respiration A modified form of respiration, anaerobic respiration, does not use oxygen. Anaerobic respiration gives less energy than aerobic respiration, producing a net gain of only two molecules of ATP for each molecule of glucose. It occurs in muscles when prolonged or hard exercise has used up their oxygen supply. It also occurs in many anaerobic microorganisms, such as the tetanus bacterium, and in yeast, which is a type of fungus. Yeast produces ethanol (alcohol) as a by-product of anaerobic respiration, a property exploited in the brewing industry to make wine and beer. Cell Processes THOUSANDS of complex chemical reactions take place inside living cells every second. For example, molecules such as proteins, lipids, and carbohydrates are made by joining smaller molecules together. In plant cells, food is made through a process called photosynthesis. In multicellular organisms, cell division produces cells that become specialized to carry out particular functions. The energy required to fuel all these processes is obtained from glucose molecules, through a process called respiration. Photosynthesis Photosynthesis is a chemical process used by plants and many microorganisms to convert the inorganic compounds carbon dioxide and water into organic compounds (carbohydrates), using the Sun's energy to drive the reaction. It is the most important synthetic process in the living world. About 50 billion tonnes of carbon are fixed into organic compounds by photosynthetic organisms each year, much of this by phytoplankton living in the surface of the oceans. ...read more.

Conclusion

The NADPH and ATP produced during the light reaction are then used to reduce these GP molecules to two molecules of a 3-carbon sugar, glyceraldehyde 3-phosphate (GALP). Some of the sugar molecules are removed to be converted into glucose, and the remainder are converted into new molecules of ribulose biphosphate, allowing the Calvin cycle to be repeated. The glucose molecules are then converted into starch for short-term storage. The products of carbon fixation are not only used for energy - they can also be converted into structural and genetic compounds, such as carbohydrates, proteins, lipids, and nucleic acids. Carbon Fixation in Tropical Plants Certain tropical plants, such as sugar cane and maize, can capture carbon dioxide with a substance called phosphoenol pyruvate (PEP), before releasing the carbon dioxide into the Calvin cycle. These plants are called C4 plants because the immediate product of carbon fixation is a 4-carbon compound. (Other plants are called C3 plants because the first stable product of fixation is the 3-carbon compound GP.) C4 plants have an exceptionally high affinity for carbon dioxide, which enables them to photosynthesize more effectively than C3 plants in very bright sunlight and at high temperatures - conditions often found in tropical environments. Certain desert plants use the C4 system to store carbon dioxide during the day and convert it into carbohydrates at night. This allows them to keep their stomata closed during the heat of the day, preventing water loss, and to open them at night, allowing gas exchange and the Calvin cycle to take place. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Energy, Respiration & the Environment section.

Found what you're looking for?

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

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Energy, Respiration & the Environment essays

  1. Marked by a teacher

    effect of temperature on the rate of respiration in yeast

    5 star(s)

    * After 5 minutes I will use thermometer to check the temperature again and it its decreased then I will add some more hot water. * When the temperature reaches 60 oC again I will take out the test tube.

  2. Marked by a teacher

    An investigation into the effect of different sugars on respiration in yeast.

    5 star(s)

    This is because the first stage of glycolysis (see diagram, page 1) begins with glucose, which breaks down into glucose 6-phosphate, which then breaks down into fructose 6-phosphate. Fructose would miss the first two stages of glycolysis, and break down straight into fructose 6-phosphate However this is a later stage

  1. Marked by a teacher

    To make sure we have plenty of energy in the future, it's up to ...

    4 star(s)

    She is the 1993 Presidential Award for Elementary Science Teaching recipient as well as winner of the 1994 Exemplary Elementary Science Teacher for the Council of Elementary Science International and the 1994 Conservationist Teacher of the Year for the Southeastern United States.

  2. Marked by a teacher

    ATP or Adenosine Triphosphate.

    3 star(s)

    This ratchet mechanism involves the use of ATP and is essential for muscle contraction. Locomotion is also a type of movement in living organisms such as sperm cells, which have an abundant supply of mitochondria in the middle piece allowing it to swim up the fallopian tube and eventually fuse

  1. Marked by a teacher

    The Role of the Respiratory and Circulatory Systems in the Provision of Oxygen and ...

    3 star(s)

    The trachea then connects the pharynx to the lungs. The trachea is composed of incomplete rings of cartilage and is lined with ciliated epithelium and goblet cells. As the cartilage rings are incomplete, it enables the trachea to be more flexible and thus facilitating the passage of food down the oesophagus.

  2. the effect of bile concentration on the activity of the enzyme lipase during the ...

    * http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2031934&dopt=Abstract - Used for background information on digestion of fats. The information from this website can be seen as accurate and reliable because it was obtained from a journal written by Department of Pediatrics, Georgetown University Medical Center, Washington, D.C.

  1. An investigation into the effects of temperature on the rate of anaerobic respiration of ...

    19 23 22 29 29 41 Length of bubbles 169 196 1296 441 361 529 484 841 841 1681 6839 683.90 To prove whether the above statement is also correct for the difference between means for 35 �C and 50�C, I will use the z test for the results at 25 minutes.

  2. Energy absorbed by a bouncing ball.

    I have also decided to plot a graph of the initial height and the fraction of energy absorbed by the ball after the bounce. Each graph will help me to identify any possible relationships between the data. For both graphs I have plotted my results for each ball onto the

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work