Hello Students Day 1 - Evening Coffee with NEET

HELLO STUDENTS: DAY-1 Evening

1.Minerals Deficiency Diseases in Plants:

*Die back of Citrus - Copper

*Reclamation disease -Copper

*Yello tip of Oat-Copper

*Exanthema in Citrus-Copper

*Hooked leaf tip -Calcium

*Little leaf of grape veins- Zinc

*Mottle leaf of Citrus-Zinc

*Rosette of Apple-Zinc

*Khaira disease of Rice-Zinc

*Brown Heart rot of Turnip-Boron

*Internal Cork of Apple-Boron

*Whiptail of Cauliflower -Molybdenum

*Whiptail of Cabbage- Molybdenum

*Curled leaf margin-Potassium

*Yellow disease of Tea- Sulphur

*Chlorosis of Pine apple -Iron

2.Facts on Plant Hormones or Phytohormones:

*Gaseous plant hormone is Ethylene(a liquid called ETHEPHON is used to release Ethylene).

*Artificial ripening of fruits is done by Ethylene.

*Epinasty is caused by Ethylene.

* Stress hormone in plant(Stress phyto hormone) is Abscisic acid.

*Plant hormone promote abscission and senescence is ABA.

*Closing of the stomata is caused by a plant hormone Abscisic acid (ABA)

*Examples for Natural Auxin : Indole Acetic acid (IAA),Phenyl Acetic acid(PAA),Indole Butyric acid (IPA)

*Examples for Synthetic Auxin:2,4-Dichloro Phenoxy Acetic acid (2,4-D),Napthalene Acetic acid (NAA),2,4,5-Trichloro Phenoxy Acetic acid (2,4,5-5)

*Apical dominance is by Auxins

*Auxins used to eradicate weeds(weed killer).

*Avena seedlings curvature Test is a Bioassay for Auxin (or)IAA.

*Bolting (sudden elongation of stem followed by flowering) is caused by Gibberellins

*Bakanae disease or Foolish Seedling disease is caused by a fungus ,Gibberella fujikurai.(Studied in Japan by Eiichi Kurusowa in1926)

*Abscission is prevented by Auxin.

*Anti-gibberellin and Anti- auxin hormone is Abscisic acid.

*Substitute for low temperature for flowering is given  by Gibberellins.

*Gibberellin breaks dormancy in potato tubers.

*Auxins were isolated initially from human urine.

*GA3 is the first discovered gibberellin.

*Gibberellin was crystallized by Yabuta and Suniki in 1938.

*Gibberellin  initiates to produce male flowers in Cucurbits.

*Gibberellin called as gibberellic acid by Brain et al.

*Richmond Lang Effect (delaying the process of ageing in plants) is promoted by Cytokinin.

*Cytokinin  promotes cell division .

*Auxin (IAA) and Cytokinin (Kinetin) collectively initiates bud and root development in Callus(unorganised mass of undifferentiated tissue in tissue culture).

*Cytokinin found in Zea mays is called Zeatin.

*The plant hormone found in endosperm of coconut is Cytokinin.

*The hormone abundantly found in embryos ,developing fruits and roots is Cytokinin.

*Cytokinin was first isolated from Herring fish sperm DNA by Miller and Skoog.

*Chemical name of Kinetin is 6- Furfuryl Amino acid .

*Free auxin is IAA.

*Bound auxin is IAA-Aspartic acid .

*Precursor of IAA is amino acid Tryptophan .

*Zinc is essential for synthesis of Tryptophan.

*Anti- auxins are 2,4,5-Tri Iodine Benzoic Acid(TIBA) and Napthylpthalamine.

*The term auxin is first used by F.W.Went in 1926 and isolated auxin from Oats(Avena).

*The unilateral growth and curvature of Canary grass (Phalaris canariensis) coleoptile to light is observed in 1880 by Charles Darwin.

*Mixture of two Phenoxy herbicides 2,4-D and 2,4,5-T is given the name "AGENT ORANGE" which was used by USA in Vietnam War for defoliation of forest (Chemical warfare).

3.Important Vital Stains used in Cytological Techniques:

*EOSIN is used to stain Cytoplasm (Pink).

*FEULGEN'S STAIN is used to stain DNA(Purple).

*JANUS GREEN B is used to stain Mitochondria and Fungi(Green).

*METHYLENE BLUE is used to stain Golgi bodies and Yeast (Blue).

*TOLUDINE BLUE is used to stain RNA(Blue).

*HEMATOXYLINE is used to stain Nucleus and Cell Wall (Violet).

4.Absent (devoid of / lack of /not found )cases in plants :

*Phloem parenchyma, Phloem fibres Vascular cambium, Secondary growth and Shoot hairs( Trichomes) are absent in MONOCOTS.

*Xylem vessels or Trachae are absent in Gymnosperms EXCEPT Gnetum ,Ephedra and Welwitschia.

* Xylem fibres , Companion cells and Sieve tubes are absent in GYMNOSPERMS.

*Phloem fibres,Xylem fibres and Tracheids are absent in Dicot leaves.

* Vessels are absent in few angiopermic families Winteraceae,Tetracentraceae and Trochodendracae.

By

Mr.R.Soundarapandian, MSc, MEd, MPhil, 

PG Asst Zoology Sir 

MCTM Boys Higher Secondary School, 

Purasawalkam Chennai-84.