1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Grace [21]
3 years ago
5

Plants maintain higher levels of phytochrome at their growing tips where phytochrome plays important roles in growth responses t

o light. Phytochrome levels are also high in areas of the plant that are "greening". What does this suggest about the role of phytochrome in these "greening" zones?
Biology
1 answer:
Naddika [18.5K]3 years ago
6 0

Explanation:

Phytochrome is a protein with kinase activity present in plant organisms, whose function is to act as a photoreceptor mainly of red light (600-700nm) and distant red light (700-800nm), thanks to its chromophore. The phytochrome depending on the type of light detected can trigger different responses in the plant, such as flowering, germination, growth as an escape response to the shadow -development of epicotyls at night and cotyledons during the day-, regulation of expression of metabolic activity during day and night (circadian rhythms).

Phytochromes were discovered in the fifties as part of an investigation on the effect of light on the germination of lettuce seeds. It was observed that the seeds that germinated in the dark did not reach 20%; On the contrary, the germination percentage was maximum when the seeds were irradiated with a pulse of red light (R). It was also found that subsequent irradiation with a pulse of distant red light (RL) nullified the inducing effect of red light, preventing germination.

Alternating irradiation with light R and RL (R, R + RL, R + RL + R, R + RL + R + RL, etc.) showed that the last color applied determined the germination of the seeds and that the light red was the stimulating factor of the process and, its inhibitor, the distant red light.

In search of an explanation of such phenomena, the existence of a pigment was proposed, which they called phytochrome, which absorbed the red light. The phytochrome in question, after absorbing red light, became a way capable of absorbing distant red radiation; form that turned to its initial condition after performing said absorption. The hypothesis found experimental support in the early sixties with the purification, from extracts of cereal seedlings, of a protein endowed with the predicted characteristics. Phytochromes are soluble proteins found in the seeds, leaves, stems, roots and other organs of the plant.

Biochemically, phytochrome is a protein with a Bilin chromophore.

You might be interested in
Ally thinks she is pregnant because she has not had her period in two months. the hormone responsible for her lack of menstruati
Delvig [45]
The menstrual cycle is regulated by two hormones secreted from the pituitarygland, follicle stimulating hormone (FSH<span>) and luteinizing hormone (LH).</span>
8 0
3 years ago
i need someone that knows history and everything about slavery to repsond ASAP will give branliest for the best answer
Alborosie

Answer:

i know some whatcha need?

Explanation:

8 0
2 years ago
Phenylketonuria is a(n) _______ disorder, meaning that it is passed from generation to generation via DNA.
dimaraw [331]

Answer:

inherited

Explanation:

Phenylketonuria is a(n) inherited disorder, meaning that it is passed from generation to generation via DNA.

6 0
1 year ago
How will the diversity of species differ between early and late succesion areas?
Vesnalui [34]
You could argue that in early succession areas species may have not been adapted or evolved. In Darwin's theory, life began in a shallow, warm pond. If that is the case, species would then venture deeper when their area they are in is suitable and having success
4 0
3 years ago
Explain how contact lenses can be a source of DNA.
sergejj [24]

Answer:

A contact lens (CL) can act as a vector for microorganisms to adhere to and transfer to the ... Thus, this detailed understanding of lens-related bioburden is important in the ... There are many other speculative causes of inflammation (lens deposits or ... Silver ions interact with the DNA of bacteria preventing cell reproduction, ...    

A contributor to this problem has been our sketchy understanding of the normal ... and of the microbes that are leading causes of contact lens-associated infection, ... During contact lens wear microbes can enter the eye from the wearer's lid ... Lessons from DNA microarray analysis: the gene expression profile of biofilms.

Explanation:hope this helps

4 0
2 years ago
Read 2 more answers
Other questions:
  • By signing the Kyoto Protocol, a country commits to decrease its greenhouse gas emissions. Which ecological issue does this prot
    6·1 answer
  • The term used to describe a cluster of spherical bacteria is
    5·1 answer
  • The total amount of organic matter present in any trophic level is called A) bioassay. B) biodiversity. C) biomass. D) detritus.
    11·1 answer
  • 1. The Devonian period is considered the Age of Fishes. Would you expect
    9·1 answer
  • Why is food, water, clothing and shelter consider to be a measurement of need?
    13·1 answer
  • Which of the following is a monosaccharide?
    5·2 answers
  • Please help ASAP !! <br><br> punnet squares- biology
    9·1 answer
  • Think of some traits in people, plants, or animals. Describe one trait and tell whether you think the trait is a dominant/recess
    5·1 answer
  • Scientists think that red pandas and raccoons share a more recent common
    14·1 answer
  • 3.<br> What two molecules are produced during Photosynthesis?
    15·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!