<h3>Phototropism</h3>
Yes, the given activity is a correct example which describes phototropism
Phototropism is an adaptation or a survival mechanism undertaken by some plants to receive maximum sunlight in order to prepare more food and energy through photosynthesis.
Explanation:
Phototropism takes place through receptor proteins called phototropins which act as blue light photoreceptors.
Phototropic activity:
Phototropism can best be observed by planting few plants including phototropic plants in pots and keeping them near the window to receive sunlight.
The natural bending of phototropic plants towards the window denotes their inclination towards sunlight.
The growth of sunflower plants facing towards the sun and blooming of lotus flower under sunlight are all examples of phototropism.
Other plants which are phototropic are Phalaenopsis, azuki beans, fungus of Phycomyces species, etc.
<span>Discovery</span>
The operon model (Lac operon) of the regulation
of gene expression in bacteria was proposed by Jacob and Monod and hey got
noble prize in 1965 in Physiology and Medicine for this discovery.
Definition
<span> “</span><span>Operons are cluster of coregulated bacterial
genes which regulate other genes responsible for protein synthesis” </span>
Explanation
<span>Operons were first studied
in the bacterium E.coli, and they
involve the enzyme of lactose metabolism and tryptophan biosynthesis. </span>
Structure of Operon
<span> </span>Operon is generally
composed of three basic DNA components:
1. Promotor:
<span> It is a nucleotide sequence which is
recognized by RNA polymerase and initiate transcription.</span>
2. Operator:
It is a segment of DNA
that is present between the promotor and other genes to be transcribed. In presence
of repressor, RNA polymerase is physically obstructed and cannot transcribe the
genes. In the absence of repressor, operator is active and start transcription
of other proteins.
3. Structural genes:
<span>These genes are
responsible for synthesis of targeted proteins under the influence of operator<span>. </span></span>
Example of operon model:
<span> In bacteria two operon model have been
extensively studied, these are:</span>
<span> a. Lac Operon, and</span>
<span> b. Tryptophan operon</span>
Answer:
- the arrow between the kit fox and a coyote.
- the arrow between the grasshopper mouse and the red-tailed hawk.
- the arrow between the grasshopper mouse and the rattlesnake.
- the arrow between the grasshopper mouse and the coyote.
- the arrow between the rattlesnake and a red-tailed hawk.
Explanation:
All of the options show matter moving from secondary consumers to tertiary consumers.
Hope it helps.