Life Science(Biology)

      Stem cutting is the simplest way of artificial vegetative plant propagation in which 4"--30" long stem piece with two nodes  is cut off just below the leaf-node and transferred to rooting media , after which planted with new roots .    Stem are of four types: (i) Hardwood cuttings    (a) Mature hardwood of woody species is selected as mother plant.    (b)  Season : Late fall to early spring for deciuous plants and late fall to late winter for evergreen plants .    (c) Stem length : 4"--30" in case of deciduous plants and 4"--8" in case of evergreen plants.   For deciuous plants cuttings may be of mallet   , heel  or straight  .      In straight only the reguired stem is cut off . A mallet is the required stem with short section of older stem but in heel entire section of old wood is kept .  e.g. Roses, Apple,Pear, Thuja etc. (ii) Semi-hardwood cuttings   (a) Stem is s...

Unit l 1. Define saltatory conduction .                                                 2, 2016,2019 2. Two important properties of reflex action .      3, 2016 3. Origin, course, termination of Gall and Burdech tract.  5, 2016                       ************** 4 What is Oligodendroglia ? Mention its function .   1+2 ,2016 5 Define chronaxic & rheobase . 1+1, 2016 6. Histological structre of skin with labeled diagram.        5, 2016                        ************** 7. What is EPP & MEPP ? 1+1, 2016 8. Differentiate between synaptic  and neuromuscular junction .   3, 2016 9. What is neurotransmitter ? Name two amino acids that acts as neurotransmitter.       ...

  The imbalance between free radicals and antioxidants in the human body results in oxidative stress.   Oxidative stress and benifits : * During exercise free radicals formed in high amount  which resulted in temporary oxidative stress   in the muscle . These free radicals regulate tissue growth and also stimulate antioxidant production.   * Mild oxidative stress protect us from many infections & diseases.    Oxidative stress and harmful activities: * Inflamations:  When there is any bacterial infection macrophages involved in the  fight with the microbes   release free radicales which damage healthy cells to cause inflammation. If there is any kind of oxidative stress during inflammation it causes more release of free radicals to make further oxidative stress & if it is in chronic state then results in diabetes, cardiovascular disorders, arthritis ,etc. *Neurodegeneration & oxidative stress:    Generally ...

(1)Define  cistron .         Cistron  is a segment of DNA coding for a polypeptide .        (It is a segment of DNA containing the genetic information for the sequence of amino acids of a  polypeptide chain i.e. the blueprint of a protein is actually stored in DNA as a cistron). (2)Define  intron and exon .           In Eukaryotes, the structural gene is monocistronic and coding sequences are interrupted by intervaining sequences.       Coding sequences are expressed as exons and intervaining sequences  are expressed as introns in pre -mRNA/ hn RNA during transcription process .Introns are excised by spliceosome at  processing time and only exons are appeared  and joined to make a mature/processed RNA.  The monocistronic structural genes are also known as  split gene. (3)  Define transcription .         The process of copying/transfer of g...

(1)  *What is neurotransmitter?        * Name 2 amino acids act as transmitter agents .       2+(1+1),2016 (2) Write down the biosynthetic pathway of ACh .                           3, 2017 (3) Name 1 exeitatory and 1 inhibitory neurotransmitter.            1+1, 2017 (4) Name 2 inhibitory neurotransmitter and 1 chemical agent that blocks neuromuscular transmission .   1+1, 2015 (5) What is Serotonin? State its role as a neurotransmitter .                        1+2,2018          Neurotransmitters  are the chemical substances released at  the nerve endings to transmit nerve impulse to a muscle fibre / postsynaptic neurone/a gland from the presynatic neurone .       A few neurotransmitters : (1) Biogenic amines     ...

(1) What is Neuroglia ?Mention its function .                      5+2=7,2017 Neuroglia is the supporting/interstitial and insulating tissue present in the both the grey and white matter of Central Nervous System (CNS) and composed of three types of cells : (1) Astrocytes                        *Fibrous and                        *Protoplasmic  (2) Oligodendroglia or       Oligodendrocyte and (3) Microglia .     Number of neuroglia is 10--15 times than the neurones of CNS. Astrocytes    (i) Star shaped cells with many radiating cytoplasmic processes. (ii)Fibrous types have more intermediate filaments and present in white matter . (iii) Protoplasmic types are resent on the grey matter . (iv) Cytoplasmic processes may attach to capillaries , neurones and synapse . ...

Paper lll ,FM..40,Time..2 hours Ans any 4, selecting 2 from each unit            Unit....l 1 (a) Define Systematics.    (b) What do you mean by binomial      nomenclature ? Give one example .    (c) What is Linnaean Hierarchy? Discuss biological species concept in short .                                       2+(2+1)+(2+3)=10 2 (a) Define adaptation .What do you mean by secondary aquatic adaptation?    (b) Describe the structural and  physiological adaptations in Camel.                                         (2+2)+(3+3)=10 3. Write short notes on / Answer any two of the following:.   5X2=10 (a) Bayesian and Mullerian mimicry with examples (b) Classify Phylum Annelida upto subclass with examples. (c)Pre-zyg...