Insights Learning (I-Learning) TEST 26 : 25 February – 04 March 2018
- Types of roots
There are two main types of roots according to origin of development and branching pattern in the angiosperms: taproot system and fibrous system.
The taproot system enables the plant to anchor better to the soil and obtain water from deeper sources.
In contrast, shallow-rooted plants are more susceptible to drought but they are quick to absorb surface and irrigation water and thus have the ability to respond quickly to fertilizer application. The table below precisely captures the differences.
|BASIS FOR COMPARISON
|FIBROUS (ADVENTITIOUS) ROOT
|Such roots which develop into primary root arising from radicle (embryonic root), these become the main root of the plant,with secondary, tertiary and other lateral branches.
|Such roots that arise from other parts of the plants like stems, or leaves other than roots are called fibrous or adventitious root.
|It develops from the radicle of the embryo.
|It develops from the stem, leaves or places other than radicle.
|Features of root
|Consist of a persistent primary root.
|Consist of the short-lived root.
|These are deep-rooted.
|Can be either underground or aerial.
|Taproot consists of only one long and main root.
|Multiple root systems.
|It can be the surface feeder or deep feeder.
|The root system of this type is the surface
|Can survive in the drought area.
|Cannot survive in drought and will dry out easily, but quick in absorbing surface and irrigation water.
|The tap root systems occur in dicots plants.
|The fibrous or adventitious root system occurs in monocots.
|Leaves have reticulate venation.
|Leaves have parallel venation.
|Carrot, Reddish, Beets.
|Onion, Grass, Wheat, Coconut palm.
Q Source: Additional Research: Chapter 7: 6th Science NCERT
They are macromolecular biological catalysts. Enzymes accelerate chemical reactions.
- Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life.
- Some enzymes are used commercially, for example, in the synthesis of antibiotics.
- Some household products use enzymes to speed up chemical reactions: enzymes in biological washing powders break down protein, starch or fat stains on clothes.
Most enzymes are proteins, although a few are catalytic RNA molecules.
Enzyme activity can be affected by other molecules: inhibitors are molecules that decrease enzyme activity, and activators are molecules that increase activity.
Many therapeutic drugs and poisons are enzyme inhibitors. An enzyme’s activity decreases markedly outside its optimal temperature and pH.
Source Additional Research: Based on reactions in plants in Chapter 7: 6th NCERT: Science
- The Global Alliance for National Human Rights Institutions (GANHRI)
Formerly known as the International Coordinating Committee of National Human Rights Institutions, sometimes shortened to the International Coordinating Committee (ICC), is a global network of national human rights institutions (NHRIs) – administrative bodies set up to promote, protect and monitor human rights in a given country.
The GANHRI accreditation system has evolved and been strengthened over past years by which NHRIs are reviewed on periodic basis of 5 years.
The ICC (now GANHARI):
- Facilitates and supports NHRI engagement with the UN Human Rights Council and Treaty Bodies
- Encourages cooperation and information sharing among NHRIs, including through an annual meeting and biennial conference
- Undertakes accreditation of NHRIs in accordance with the Paris Principles
- Promotes the role of NHRIs within the United Nations and with States and other international agencies
- Offers capacity building in collaboration with the Office of the High Commissioner for Human Rights (OHCR)
- Assists NHRIs under threat
- If requested, can assist government to establish NHRIs
The National Human Rights Commission (NHRC) has retained its ‘A’ status of accreditation of GANHRI for fourth consecutive term
It refers to the beneficial or harmful effects of one plant on another plant, both crop and weed species, from the release of biochemicals, known as allelochemicals.
- It is a process by which a plant releases chemicals that can inhibit its competitors.
- Soil sickness, a general term for a problem that may well be caused by residues of allelochemicals that persist in the soil after the plant is gone, may make some sites unsuitable for growing other plants.
- Allelopathic chemicals can be present in any part of the plant. They can be found in leaves, flowers, roots, fruits, or stems.
- They can also be found in the surrounding soil. The toxic chemicals may inhibit shoot/root growth, they may inhibit nutrient uptake, or they may attack a naturally occurring symbiotic relationship thereby destroying the plant’s usable source of a nutrient.
Source Additional Research: Chapter 7: 6th NCERT: Science
- Algal Bioreactor (PBR)
PBR is an enclosed, lighted, algal culture vessel designed for controlled production of algae.
Photo bioreactors, have several major advantages over open ponds, they can:
Prevent contamination: One of the biggest problems with opens ponds (in my view anyway) is they are susceptible to contamination from invading and/or native species. In a PBR all inputs are completely controlled by you, not chance or nature. This is a HUGE advantage.
Allow you to grow algae in any climate: This is one of the main reasons for a PBR. It allows you to grow algae easily and cheaply in almost any climate. Open ponds are an unacceptable alternative in many colder climates.
Bioreactors offer better control over existing conditions: Since you’re controlling all the inputs, you can also (better) control the existing conditions of your algal experiments. Meaning climate, light, temperature, Ph balance, nutrients, etc.
Permit higher cell concentrations: Because you’re controlling the parameters of the PBR, you can also control the density of your cell colonies. While possible in an open pond, it is much easier in a PBR.
However, it is costly, difficult to set up and requires technical expertise which is not easy to come by for an ordinary algae farmer with limited resources.
Source: https://en.wikipedia.org/wiki/Algae_bioreactor : It is an important topic.