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✅ Vocabulary |
1. HUDDLE (VERB):crowd
Synonyms: gather, throng
Antonyms: disperse
Example Sentence:They huddled together for ensuring warmth.
2. BANDY (ADJECTIVE): bowed
Synonyms: curved, bent
Antonyms: straight
Example Sentence:She had legs that were bent and slightly bandy.
3. MARSHAL (VERB): gather
Synonyms: assemble, collect
Antonyms: disperse
Example Sentence:The general marshalled his troops for an important task.
4. FIERCE (ADJECTIVE): powerful
Synonyms: strong, violent
Antonyms: mild
Example Sentence:Fierce storms lashed throughout the country.
5. SHED (VERB)dismiss
Synonyms: let go, discharge
Antonyms: hire
Example Sentence:Many firms use relocation as an opportunity to shed jobs.
6. ILLICIT (ADJECTIVE): illegal
Synonyms: unlawful, illegitimate
Antonyms: licit
Example Sentence:She was in possession of illicit drugs.
7. DESTRUCTIVE (ADJECTIVE) negative
Synonyms: hostile, antagonistic
Antonyms: constructive
Example Sentence:One should never practice destructive criticism.
8. REPREHENSIBLE (ADJECTIVE) deplorable
Synonyms: disgraceful discreditable
Antonyms: creditable
Example Sentence:His complacency and reprehensible laxity.
9. ZEAL (NOUN)passion
Synonyms: ardour, love
Antonyms: apathy
Example Sentence:He has a lot of zeal for privatization.
10. INTERDICT (VERB): prohibit
Synonyms: forbid, ban
Antonyms: permit
Example Sentence:Society will never interdict morality.
💙 Vocabs 💙
﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏
🔴 DILIGENT
Syno-- Assiduous, Tireless
Anto-- lazy, Torpid
﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏
🔴 PANDEMONIUM
Syno-- Ruckus, noise
Anto-- calm, silence
﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏
🔴 BUSTLE
Syno-- Hurry, Scoot, Scuttle
Anto-- peace, stillness
﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏
🔴 RESILIENT
Syno-- Bouncy, Springy
Anto-- rigid, inflexible
﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏
🔴 MINGY
Syno-- Cheapskate, Stingy, ungenerous
Anto-- Openhanded, Generous
﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏
🔴 ADIPOSE
Syno-- Obese, Fat, Portly
Anto-- Lean, Stringy
﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏
🔴 BEGUILE
Syno-- Cheat, Mislead, Deceive
Anto-- Expose, Reveal
﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏
🔴 Destitute
Syno-- poor, beggared
Anto-- rich
﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏﹏
✅ Vocabulary
1. UNDERPIN (VERB): promote
Synonyms: nurture, encourage
Antonyms: hinder
Example Sentence: The theme of honour underpinning the two books.
2. IMPRUDENT (ADJECTIVE) unwise
Synonyms: injudicious, incautious
Antonyms: prudent
Example Sentence: It would be imprudent to leave her winter coat behind.
3. INCURSION (NOUN): attack on
Synonyms: assault on, raid on
Antonyms: retreat
Example Sentence: Soldiers went for incursions into enemy territory.
4. EXACERBATE (VERB) aggravate
Synonyms: worsen, inflame
Antonyms: calm
Example Sentence:The exorbitant cost of land in urban areas only exacerbated the problem.
5. CATASTROPHE (NOUN)/disaster
Synonyms: calamity, cataclysm
Antonyms: salvation
Example Sentence: An environmental catastrophe has hit the country.
6. SLENDER (ADJECTIVE)meagre
Synonyms: limited, slight
Antonyms: considerable
Example Sentence: He helped people of slender means.
7. DIGNIFIED (ADJECTIVE)stately
Synonyms: noble, courtly
Antonyms: undignified
Example Sentence: She maintained a dignified silence.
8. PROFOUNDLY (ADVERB) extremely
Synonyms: very, deeply
Antonyms: superficially
Example Sentence:He profoundly altered the whole course of my life.
9. OPPRESSIVE (ADJECTIVE )harsh
Synonyms: cruel, brutal
Antonyms: lenient
Example Sentence: They survived an oppressive dictatorship.
10. RETREAT (VERB)go out
Synonyms: ebb, recede
Antonyms: come in
Example Sentence: It becomes so hot that the lizards retreat into the shade.
🚨 Vocabulary 🚨
1. DISCLOSURE (NOUN)revelation
Synonyms: divulgence, declaration
Antonyms: concealment
Example Sentence:
A judge ordered the disclosure of the government documents.
2. BAR (VERB) prohibit
Synonyms: debar, preclude
Antonyms: admit, accept
Example Sentence:
Journalists had been barred from covering the elections.
3. SANCTIFY (VERB): consecrate
Synonyms: bless, ordain
Antonyms: deconsecrate
Example Sentence:
He was consecrated bishop of York.
4. FURNISH (VERB): supply
Synonyms: equip, provide
Antonyms: divest
Example Sentence:
Fish furnish an important source of protein.
5. INCONSPICUOUS (ADJECTIVE): unnoticeable
Synonyms: unobtrusive, unremarkable
Antonyms: conspicuous, noticeable
Example Sentence:
That was an inconspicuous red-brick building.
6. ADHERE (VERB)abide by
Synonyms: stick to, hold to
Antonyms: flout, ignore
Example Sentence:
All drivers must adhere to speed limits.
7. CONTEND (VERB) face
Synonyms: cope with, grapple with
Antonyms: surrender, allow
Example Sentence:
She had to contend with his uncertain temper.
8. VINDICATE (VERB) justify
Synonyms: warrant, substantiate
Antonyms: disprove
Example Sentence:
More sober views were vindicated by events.
9. STAMPEDE (NOUN)panic
Synonyms: rush, flight
Antonyms: retreat, standing
Example Sentence:
The herd was fleeing back to the high land in a wild stampede.
10. DISCOURSE (NOUN): discussion
Synonyms: conversation, talk
Antonyms: silence
Example Sentence:
They understand the language of political discourse only.
●▬▬▬▬⚜۩۞۩⚜▬▬▬▬●
✅ Vocabulary
1. VAUNT (VERB)acclaim
Synonyms: esteem, revere
Antonyms: criticize
Example Sentence: He was initially vaunted by the West for his leadership of the country.
2. UNSEEMLY (ADJECTIVE): indecorous
Synonyms: improper, inappropriate
Antonyms: seemly
Example Sentence:The discussion led to nothing but an unseemly squabble.
3. CATHARSIS (NOUN): purging
Synonyms: purgation, purification
Antonyms: repression
Example Sentence: Music is a means of catharsis for many of us.
4. INFANTILE (ADJECTIVE): childish
Synonyms: babyish, immature
Antonyms: mature
Example Sentence: The point about fairies etc. is so infantile in logic I can barely contain my disbelief.
5. INGRAINED (ADJECTIVE): entrenched
Synonyms: established, fixed
Antonyms: transient
Example Sentence: She wanted to wake up with his scent ingrained in her skin.
6. CELLAR (NOUN): basement
Synonyms: vault, crypt
Antonyms: attic
Example Sentence: The servants led us down into a cellar.
7. OMINOUS (ADJECTIVE):
threatening
Synonyms: menacing, baleful
Antonyms: promising
Example Sentence: My ominous tone didn’t register with him.
8. MALAISE (NOUN) unhappiness
Synonyms: restlessness, uneasiness
Antonyms: comfort
Example Sentence: An infected person will feel a general malaise.
9. STRICKEN (ADJECTIVE)troubled
Synonyms: affected, afflicted
Antonyms: unaffected
Example Sentence: The pilot landed the stricken aircraft.
10. OSTENSIBLE (ADJECTIVE):apparent
Synonyms: seeming, outward
Antonyms: real
Example Sentence: The real dispute which lay behind the ostensible complaint.
*💤Homonyms*
*Homonyms are words in the English language that have the same spelling, and even the same (or very similar) pronunciation, but has two distinctly different meanings. The origin and the syntax of the words will also differ, while the spelling remains the same. You can see how this can be confusing, right?*
*Let us take an example to showcase this confusion. One just funny sentence, often attributed to American writer and comedians Groucho Marx is as follows, “time flies like an arrow; fruit flies like a banana.” The first ‘flies’ here is a verb and implies the act of flying away fast. The second ‘flies’ is a noun, as in fly the insect*.
🔥 *Homographs and Homophones*🔥
*There are actually two types of homonyms. When the words have the same spelling, and yet have different meanings we call them homographs. here the pronunciations may also differ. Take for example the word “lead”. It can mean to guide or pilot someone or something. It can also be the noun form, lead as in the metal.*
*Then we have the Homophones. These words have the same sound (pronunciation) but their spellings are slightly different. And they obviously have different meanings. Take for example the word desert and dessert. “Desert” is the barren land or to abandon something. And “dessert” is the sweets we eat at the end of a meal.*
*Synonyms*
*A synonym is a word, or in some cases a phrase that has the same meaning as another word with regards to the same language. If the meaning is not exactly the same, the words have very similar meanings in the context.*
*When two words are synonyms of one another, we call them synonymous words. Let us take the example of the word “jump”. The words leap, bounce, hop are all synonymous to jump, i.e. they have the same (or very similar) meanings*
*Antonyms*
*Now as opposed to a synonym, an antonym is a word whose meaning is exactly opposite to another word, in the same language. It originates from the Greek word “anti” which stands for opposite and “onym” which stands for “name”. For example the antonym for hot is cold, and the antonym for up is down.*
*Antonyms are actually quite useful in the English language. At times it is easy to understand the meaning and the context of a difficult word, by knowing what the opposite of the word means. Take for example the word “mundane” whose synonym is “humdrum”. The antonym for mundane is “extraordinary” or “imaginative”. Now the word mundane has much better clarity.*
*
*Now a gerund is a word that invariably ends with “-ing”, without exception. So a gerund phrase is a phrase that contains an ‘ing” word, with some modifiers in some cases. But participle phrases also have a similar pattern (-ing words), so how do you tell the difference between the two?*
*Well while participle phrases function as adjectives, Gerund Phrases exclusively function as nouns. Let us look at some examples,*
*She is currently writing her memoir.*
*Washing the dishes is Alex’s chore*
*Waking up before sunrise had become his habit*.*
*7] Absolute Phrase*
*An absolute phrase will contain a noun or a pronoun with a participle. Again it may also contain additional associative words and modifiers. An absolute participle will modify a whole clause, or even a whole sentence, not only one word. However, it does not constitute a complete sentence or a clause. Generally, an absolute phrase is separated by commas. Let us take a look at a few examples,*
*He looked towards the beggar, his face* *expressing pity*
*We were glued to the* *match, our eyes always following the ball.*
*He sat on the bed, his clothes neatly folded by his side*.*
EXAMGOD:
*Types of Phrases*
*As we know a complete sentence in grammar is made up of units. One such unit is a phrase. Let us learn about phrases, their meaning, syntax and some types of phrases that we see in English grammar like noun phrases, verb phrases, prepositional phrase etc.*
*Phrases*
*A phrase is a group or combination of two or more words. It is a unit of a complete sentence. By itself, a phrase is not a complete sentence, as it does not relay a complete thought. It does not contain the subject and the predicate both, so it is not a clause either.*
*The length of the phrase may differ from two words to many more words. This does not have any connection to whether it is a phrase or a sentence. For example “old dog” is a phrase. So is “the old, smelly, shivering dog” is also a phrase*.
*Types of Phrases: Noun Phrase, Verb Phrase, Prepositional Phrase etc.*
*Explanation of Types of Phrases*
*1] Noun Phrases*
*These are the phrases contains a noun- name, place or things and at least one modifier associated to the noun. The modifier can prefix or suffix the noun. The entire phrase will act as a noun for that particular sentence. Here are some examples,*
*He was wearing a black linen shirt.*
*They lived in a small, tidy cottage*
*Alex rode her old bicycle to their shiny new school*
*The black car got* *towed*.
*2] Verb Phrases*
*Every sentence will generally contain a verb. But sometimes the action being described requires a more nuanced multi-words verb phrase. The phrase consists of the main verb/verbs and then auxiliary verbs, i.e. helping verbs. Some such verb phrases are as follows,*
*The teacher is writing the answer*
*They have been playing since the last two hours*
*You must call your mom at once*
*He has taken the dog along*
*3] Prepositional Phrase*
*Any phrase that consists of a preposition, and the object of the preposition, which will be a noun or a pronoun s what we call a prepositional phrase. Such a phrase also at times consists of other modifiers describing the object of the prepositional phrase. Let us look at some examples,*
*Students are advised to be on time*
*Please turn towards the right at the intersection*
*Now there are certain times where a prepositional phrase will act as an adjective for a sentence. It will be the answer to the question* *“which one?”. For example,*
*Please get the book above the cupboard. (Which book?)*
*The student at the end of the line is misbehaving again. (Which student?)*
*And then the prepositional phrase can be seen as the adverb of a sentence. How? Where? or When? are the questions that it answers.*
*The cat is hiding behind the tree. (Where is the cat?)*
*The family headed to church after breakfast. (When did the family leave*
[1/31, 10:57 PM] EXAMGOD: *4] Infinitive Phrases*
*A phrase that includes an infinitive along with a simple verb is an infinitive phrase. There may also be modifiers attached to the object in the phrase, It contains a verb, so it plays the role of expressing an action in the sentence. Infinitive phrases can act as a noun, adjective or adverb in a complete sentence.*
*Alex likes to read comics (functions as a noun here)*
*To attend the morning lecture, I set my alarm for 6 am.* *(noun form)*
*To keep his dogs calm,* *Alex turned on the radio. (functions as an adverb here)*
*5] Participle Phrases*
*A participle phrase will begin with a participle, which can be a present participle (ending with -ing) or a past participle (ending with -ed). There may be a few modifiers and associated words included in the phrase. One thing to remember is that a participle phrase always takes the form of an adjective in a sentence. Some examples of the participle phrase are,*
*We got a call from my aunt today telling us the good news.*
*The house was severely damaged by the flood.*
*Please sit down without making a sound*
*6] Gerund Phrases*
✅ Control and Coordination
✍️Introduction
➖In multicellular organisms, following the general principles of body organization, some specialized tissues are used to provide the control and coordination activities.
✍️Nervous System
➖Nervous system is specialized system that provide control and coordination in animals.
➖All information, coming from our environment is detected by the specialized tips of some nerve cells, which are usually located in sense organs.
➖The information, acquired at the end of the dendritic tip of a nerve cell, sets off a chemical reaction that creates an electrical impulse.
➖This (electrical) impulse, which travels from the dendrite tip to the cell body, and then along the axon to its end of the axon, sets off the release of some chemicals. These chemicals cross the gap, or synapse, and create a similar electrical impulse in a dendrite of the next neuron.
➖Likewise, the nervous tissue is made up of an organized network of nerve cells or neurons, and is dedicated for carrying information via electrical impulses from one part of the body to another.
✍️Reflex Actions
If the nerves that detect heat, cold, or any such kind of more sensational element move muscles in a simpler way; so, the process of detecting the signal or the input and responding to it by an output action, is known as reflex action and such connection is known as a reflex arc.
✍️Human Brain
➖The communication between the central nervous system and the other parts of the body is established by the peripheral nervous system.
➖Peripheral nervous system consists of cranial nerves, which arise from the brain and spinal nerves.
➖The brain facilitates us to recognize, think, and take actions accordingly.
➖The brain is categorized into three major parts or regions, namely the fore-brain, mid-brain, and hind-brain.
➖Among these three parts (of the brain), fore-brain is the main thinking part of the brain; further, fore-brain are specialized for hearing, smell, sight, etc.
➖When brain gives command, muscle moves – it happens because muscle cells have special proteins that change both their (muscle’s) shape and arrangement in the cell in response to nervous electrical impulses.
MUSCULAR SYSTEM:-❤️
• Muscle is a specialised tissue of mesodermal origin that has special properties like excitability, contractility,extensibility and elasticity. ❤️
Based on their location, three types of muscles are identified.❤️
Types of muscle:-❤️
Skeletal muscles:-❤️
These are closely associated with the
skeletal components of the body. They have a striped appearance under the microscope and hence are called striated muscles. As their activities are under the voluntary control of the nervous system, they are known as voluntary muscles too. They are primarily involved in locomotory actions and changes of body postures.❤️
Visceral muscles:-❤️
These are located in the inner walls of hollow visceral organs of the body like the alimentary canal, reproductive tract, etc. They do not exhibit any striation and are smooth in appearance.❤️
Hence, they are called smooth muscles. They are not under the voluntary control of nervous system,hence are also called involuntary muscles. They assist, for example, in the transportation of food through the digestive tract and gametes through the genital tract.❤️
Cardiac muscles:-❤️
These are the muscles of heart.Many cardiac muscle cells assemble in a branching pattern to form a cardiac muscle. Based on appearance, cardiac muscles are striated. They are involuntary in nature as the nervous system does not control their activities directly.❤️
🌟Cultivable species of fresh water fishes 🌟 -
Indigenous species :
💫1. Catla catla (Catla)
💫2. Labeo rohita (Rohu) – Most common carp
💫3. Labeo calbasu (Calbasu)
💫4. Cirrhinus mrigala (Mrigal)
💫5. Clarius batrachus (Magur)
🌟Exotic species 🌟:
-Cyprinus carpio (Common carp)
- Ctenopharyngodon idella (grass carp)
- Hypopthalmicthys molitrix (chinese carp/silver carp)
🌟 Marine fishes 🌟- are generally rich in Omega-3-fatty acids.
🌟1. Hilsa (Hilsa)
🌟2. Salmo (Salmon)
🌟3. Sardinella (Sardine)
🌟4. Harpodon (Bombay duck)
🌟5. Stomaleous (Pomfret) - Introdued in Indian sea by foreigners
🌟6. Rastrelliger (Mackerel)
⭕️Endoplasmic Reticulum⭕️
(1) Definition: It is well developed electron microscopic network of interconnected cisternae, tubules and vesicles present throughout the cytoplasm, especially in the endoplasm.
(2) Discovery: Garnier (1897) was first to observe the ergastoplasm in a cell. The ER was first noted by Porter, Claude, and Fullman in 1945 as a network. It was named by Porter in 1953.
Golgi Complex
(1) Definition: Golgi complex is made up of various membranous system e.g. cisternae, vesicles and vacuoles.
(2) These are also called golgi bodies, golgisomes, lipochondrion, dictyosomes, Dalton complex, idiosomes or Baker’s body.
(3) These are also called “traffic police” of the cell.
(4) Discovery: First observed by George (1867) but it’s morphological details were given by Camillo Golgi (1898), in nerve cells of barn fowl and cat .
♨️Mitochondria♨️
(1) Definition: (Gk – mito = thread ; chondrion = granule) Mitochondria are semi autonomous having hollow sac like structures present in all eukaryotes except mature RBCs of mammals and sieve tubes of phloem.
(2) These are absent in all prokaryotes like bacteria and cyanobacteria.
(3) Mitochondria are also called chondriosome, chondrioplast, plasmosomes, plastosomes and plastochondriane.
Plastids
(1) Definition: Plastids are semiautonomous organelles having DNA, RNA, Ribosomes and double membrane envelope which store or synthesize various types of organic compounds as ATP and NADPH + H+ etc.
(2) These are largest cell organelles in plant cell.
(3) History: Haeckel (1865) discovered plastid, but the term was first time used by Schimper (1883).
Notes on Plant Growth and Development
(d) Bolting and Flowering: Gibberellins induce stem elongation in ‘rosette plants’ e.g., cabbage, henbane, etc. Such plants show retarded internodal growth and profuse leaf development. In these plants just prior to the reproductive phase, the internodes elongate enormously causing a marked increase in stem height. This is called bolting.
(e) Enzyme formation: One of the most dramatic effects of GA is its induction of hydrolytic enzymes in the aleurone layer of endosperm of germinating barley seeds and cereal grains. GA stimulates the production of digestive enzymes like proteases, a-amylases, lipases which help to mobilise stored nutrients.
(f) Breaking of dormancy: Gibberellins overcome the natural dormancy of buds, tubers, seeds, etc. and allow then to grow. In this function, gibberellins act antagonistically to abscisic acid (ABA).
(g) Parthenocarpy: Gibberellins have been considered to be more effective than auxins for inducing parthenocarpy in fruits like apple, tomato and pear. GA application has also resulted in the production of large fruits and bunch length in seedless grapes.
(h) Sex expression: Gibberellins control sex expression in certain plants. In general, gibberellin promotes the formation of male flowers either in place of female flowers in monoecious plants such as cucurbits or in genetically female plants like Cannabis, Cucumis.
(3) Cytokinins (Phytokinins):
(i) Cytokinins are plant growth hormones which are basic in nature, either aminopurine or phenyl urea derivatives that promote cell division (cytokinesis) either alone or in conjugation with auxin.
(ii) Functions of cytokinins
(a) Cell division: Cytokinins are essential for cytokinesis and thus promote cell division. In presence of auxin, cytokinins stimulate cell division even in non-meristematic tissues.
(b) Cell enlargement and Differentiation: Under some conditions cytokinins enhance the expansion of leaf cells in leaf discs and cotyledons. These cells considered to be mature and under normal conditions do not expand.
(c) Delay in senescence: Cytokinin delay the senescence (ageing) of leaves and other organs by controlling protein synthesis and mobilization of resources (Disappearance of chlorophyll). It is called Richmond Lang effect.
(d) Counteraction of apical dominance: Auxins and cytokinins act antagonistically in the control of apical dominance. Auxins are responsible for stimulating growth of apical bud.
(e) Breaking of dormancy: Cytokinins breaks seeds dormancy of various types and thus help in their germination.
(f) Accumulation and Translocation of solutes
(4) Ethylene:
(i) Ethylene is a gaseous hormone which stimulates transverse growth but retards the longitudinal one.
(ii) Functions of ethylene
(a) Fruit growth and Ripening: Ethylene promotes fruit growth and its ripening. The harmone is used in the artificial ripening of climacteric fruits (e.g., Apple, Banana, and Mango).
(b) Transverse growth: Ethylene inhibits longitudinal growth but stimulates transverse growth so that stem looks swollen.
(c) Epinasty (leaf bending): Epinasty represents more growth on upper surface of leaf than on lower surface. Epinasty is said to be controlled by ethylene in many plants.
(d) Abscission: Ethylene stimulates formation of abscission zone in leaves, flowers and fruits.
(e) Apical dominance: Ethylene inhibits the growth of lateral buds and thus causes apical dominance (in pea). It is believed that auxin might be functioning partly through synthesis of ethylene in causing apical dominance.
(f) Root initiation: In low concentration, ethylene stimulates root initiation and growth of lateral roots and root hair.
(g) Flowering: Ethylene stimulates flowering in pineapple and related plants though in other cases, the hormone causes fading of flowers.
Notes on Plant Growth and Development
(1) The analysis of growth curve shows that it can be differentiated into three phases:
(i) Lag phase: It represents initial stages of growth. The rate of growth is very slow in lag phase. More time is needed for little growth in this phase.
(ii) Log phase (Exponential phase): The growth rate becomes maximum and more rapid. Physiological activities of cells are at their maximum. The log phase is also referred to as grand period of growth.
(iii) Final steady state (Stationary phase) or Adult phase: When the nutrients become limiting, growth slows down, so physiological activities of cells also slows down. This phase is indicated by the maturity of growth system. The rate of growth can be measured by an increase in size or area of an organ of plant like leaf, flower, fruit etc. The rate of growth is called efficiency index.
(2) Phytohormones:-
(i) Growth hormones also called phytohormones
(ii) Term given by Thimann (1948),
(iii) It can be defined as ‘the organic substances which are synthesized in minute quantities in one part of the plant body and transported to another part where they influence specific physiological processes’.
Growth Hormones and Growth Regulators
(1) Auxins:
(i) Auxins (Gk. auxein = to grow) are weakly acidic growth hormones having an unsaturated ring structure and capable of promoting cell elongation, especially of shoots (more pronounced in decapitated shoots and shoot segments) at a concentration of less than 100 ppm which is inhibitory to the roots. Among the growth regulators, auxins were the first to be discovered.
(ii) Types of auxins: There are two major categories of auxins natural auxins and synthetic auxins:
(a) Natural auxins: These are naturally occurring auxins in plants and therefore, regarded as phytohormones. Indole 3-acetic acid (IAA) is the best known and universal auxin. It is found in all plants and fungi.
(b) Synthetic auxins: These are synthetic compounds which cause various physiological responses common to IAA. Some of the important synthetic auxins are 2, 4-D (2, 4-dichlorophenoxy acetic acid) is the weedicide. IBA is both natural and synthetic auxin.
(iii) Functions of auxins: Auxins control several kinds of plant growth processes. These are as follows:
(a) Cell elongation: Auxins promote elongations and growth of stems and roots and enlargement of many fruits by stimulating elongation of cells in all directions.
(b) Apical dominance: In many plants, the apical bud grows and the lower axillary buds are suppressed. Removal of apical bud results in the growth of lower buds. The auxin (IAA) of the terminal bud inhibits the growth of lateral buds. This phenomenon is known as apical dominance.
(c) Weed control: Weeds are undesirable in a field with a crop. By the spray of 2, 4-D, broad-leaved weeds can be destroyed but 2, 4-D does not affect mature monocotyledonous plants.
(d) Root differentiation
(e) Control of lodging
(f) Parthenocarpy: Parthenocarpy can be induced by application of IAA in a paste form to the stigma of a flower or by spraying the flowers with a dilute solution of IAA.
(2) Gibberellins:
(i) Gibberellins are weakly acidic hormones having gibbane ring structure which cause cell elongation of intact plants in general and increased internodal length of genetically dwarfed plants (i.e., corn, pea) in particular.
(ii) Functions of gibberellin
(a) Stem elongation: The gibberellins induce elongation of the internodes.
(b) Leaf expansion: In many plants leaves become broader and elongated when treated with gibberellic acid.
(c) Reversal of dwarfism: One of the most striking effects of gibberellins is the elongation of genetic dwarf (mutant) varieties of plants like corn and pea.
💥⟨⟨HORMONES & THEIR FUNCTIONS ⟩⟩💥
1. Growth hormone (GH) Or somatotropic hormone (STH)
Function ~ stimulates growth by stimulating protein synthesis.
2. Thyroid stimulating hormone (TSH)
Function ~ stimulates thyroid secretion.
3. Adrenocorticotropic hormone (ACTH)
Function ~ stimulates the production of of steroids by adrenal cortex.
4. Gonadotropic hormones
(i) follicle stimulating hormone (FSH)
Function ~ stimulates gamate, production, secration of sex hormones, development of follicles.
(ii) interstitial cell stimulating hormone ( ICSH) or luteinising hormone (LH)
Function ~ stimulates the leydig cells of testis and induces secretion of testosterone. stimulates development of Corpus luteum and ovulation in female.
5. Luteotropic hormone ( LTH) or prolactin
Function ~ stimulates the growth of mammary glands, lactation and maintenance of Corpus luteum.
6. Melanocyte stimulating hormone
Function ~ controls dispersal of melanophores , in man it is doubtful.
7. Oxytocin
Function ~ stimulates secretion of milk from mammary glands ; causes contraction of uterus at the time of child birth.
8. Antidiuretic hormone or ADH (vasopressin)
Function ~ stimulates the nephrons for reabsorption of water.
Stimulates contraction of smooth muscles , blood vessels and causes rise in blood pressure.
9. Thyroxine (T4) and triiodothyronine (T3)
Function ~ control metabolism , regulate body temperature by calorigenic action.
10. Thyrocalcitonin (TCT)
Function ~ controls calcium (Ca++) level in blood , Check osteoporosis .
11. Parathormone
Function ~ maintains proper level of calcium and phosphorus by regulating renal action , thus , controlling calcium and phosphate amount in bones.
12. Insulin (from β cells)
Function ~ stimulates metabolism of carbohydrates. Influences the storage and utilization of sugar , inhibits hepatic gluconeogenesis stimulates glycogenesis.
13. Glucagon (from α cell)
Function ~ influences the enzymatic action of phosphorylase , controlling glycogenolysis in tha liver and muscles ; increases the amount of sugar in blood.
Antagonistic to insulin , inhibits glycogenesis.
14. Somatostatin(ss)
Function ~ suppresses the release of hormones from the pancrease and digestive track.
15. Pancreatic polypeptide
Function ~ inhibits the release of digestive secretion of the pancrease.
16. Adrenaline (epinephrine) and noradrenaline (Norepinephrine)
Function ~ Regulates heart beat , blood pressure , sympathetic nervous system , contraction of involuntary muscles of lung , eyes , gut etc. , Production of blood , flow of saliva and sweat under emotional state.
17. Adrenocorticoids
Function ~ regulate water and electrolyte balance, regulate fat, protein and carbohydrate metabolism; stimulate development of male and female secondary sexual characters.
18. Testosterone (leydig's cells)
Function ~ affects the normal development and functions of secondary sexual organs and characters in male.
~ stimulate formation of sperms.
19. Estrogen (graafian follicles )
Function ~ Affects development and maintenance of secondary sexual characters in female.
~ stimulate maturation of ova.
20. Progesterone ( ovary and Corpus luteum )
Function ~ stimulates uterus for pregnancy, implantation and formation of placenta, also stimulates mammary glands.
21. Relaxin ( Corpus luteum )
Function ~ relaxes ligaments of pelvic girdle at the time of birth.
22. Human chorionic gonadotropin or HCG (placenta)
Function ~ pravints disintegration of the Corpus luteum and maintains progesterone production.
23. Serotonin
Function ~ Helps in vasoconstriction of blood vessels.
24. Melatonin
Function ~ Reduces quantity of FSH and LH, Acts as anti gonadotropic hormone.
25. Thymosin
Function ~ regulates growth, stimulates proliferation of lymphocytes and also hastens sexual maturity.
🔰 Role of nutrients and their deficiency Symptoms 🔰
#Nitrogen
▪️Impart green colour to plant encourages vegetative growth
▪️ Nitrogen is essential constituent of protein
▪️ Constituent of Protoplasm of chlorophyll and coenzyme.
▪️ Play important role in
synthesis of auxin
#Deficiency
▪️ Lower leaves become yellow and dries.
▪️V shaped chlorosis on older leaves or yellowing at tip.
#Disease
▪️Starvation disease due to nitrogen deficiency.
▪️Buttoning in cauliflower.
#Phosphorous
▪️Increase the disease resistance.
▪️ Enhance new cell formation and necessary for root development.
▪️Required for grain formation and maturity of grains.
▪️Phosphorus is essential constituent for nucleic acid and phytin.
▪️Most essential functions are energy storage and transfer energy act as "energy currency".
#Deficiency
▪️Due to deficiency of single element the life cycle of plant can't be completed hence (Agricultureexamslibrary) Phosphorus is called " key of life "
▪️Deficiency imparts dark green colour in leaves.
▪️Later develops red purple colourration.
#Disease
▪️Sickle leaf diseases.
#Potassium
▪️Most essential function of K+ is stomata regulation.
▪️Provides disease resistance in plants.
▪️Cofactor for enzymes.
▪️Formation and translocation of Sugars.
▪️Helps in chlorophyll formation.
#Deficiency
▪️Spot of dead tissue at tips.
▪️Scorching and burning on margins of autumn leaves.
#Disease
▪️Rottle/ dieback disease.
#Calcium
▪️ It is constituent of cell wall
▪️ Calcium is a mobile in plants and deficiency symptoms appear on Meristem tip portion.
# Deficiency
▪️ Terminal bud die
#Disease
▪️Tip hooking.
▪️ Blossom end rot of tomato(BER).
▪️Popping in groundnut.
#Magnesium
▪️ Essential constituent of chlorophyll.
▪️ Magnesium is a constituent of chlorophyll.
▪️Chlorosis between veins.
#Disease
▪️Sand -drown disease of tobacco.
#Sulphur
▪️ Sulphur oxidizing Bacteria is Thiobacillus.
▪️Sulphur is essential for oil seed and pulses because it improves oil content and protein content in oil seeds and pulses, respectively.
#Disease
▪️Akiochi disease of rice due to Excess of hydrogen sulphide.
▪️Tea yellow disease of tea.
#Iron
▪️Fe is the component of nitrate reductase.
▪️Required for nitrogen fixation.
▪️During respiration act as O2 carrier.
#Deficiency
▪️Interveinal complete chlorosis.
▪️Scorching of leaf margin.
▪️Yellowing of iron chlorosis in groundnut.
#Manganese
▪️Formation of chlorophyll.
▪️Co-factor of enzyme.
▪️Mn toxicity causes crinckle leaf of cotton.
#Deficiency
▪️Dead spot on leaves.
#Desease
▪️Marsh spot of pea.
▪️Pahala blight of sugarcane.
#Copper
@agricultureexams2020
▪️Compound of plastocyanin.
▪Essential for photosynthesis/ respiration.Agriexams library
▪️Dieback and reclamation disease of cereals.
#Boron
▪ Necessary for Pollen germination.
▪️Boron is the only non-metal element among the micronutrient.
▪️It is necessary for translocation of Sugars and is involved in reproduction and germination of pollen.
#Disease : due to deficiency
▪️Browning of cauliflower is caused by Boron deficiency.
▪️Top sickness of tobacco.
▪️Fruit cracking of tomato.
▪️Hard fruit of citrus.
▪️Hen and chick disease of grape.
#Zinc
▪️In plants it is required for biosynthesis of hormones.
▪️Zn deficiency causes-
-White bud of maize.
-Khaira disease of rice.
-Little leaf of cotton.
-Mottled leaf of citrus.
-Rosette formation.
#Cobalt
▪️It is component of Vitamin B
▪️It is essential for formation of type of hemoglobin in N-fixing nodule tissue known as leghaemogloin.
▪️Act as O2 carrier in roots.
▪️Also known as animal protein factor.
#Molybdenum
▪️Mo: absorbed as molybdate MoO4-2 forms.
▪️Mo is important component of enzyme: Nitrate reductage.
▪️N-fixation in pulses.
▪️Whiptail of cauliflower is due to deficiency of Mo.
▪️Mo is required for carrot & raphanus for sweetness.
