HSEB General characteristics of phylum Chordata

The General characteristics of phylum Chordata are as follows :

1. Presence of Notochord : It is stiff, flexible and solid rod like structure which helps in supporting the internal body . It is situated between the alimentary canal and nerve chord. It may be present in the embryonic stage only or throughout the life.  Later on in an adult it is replaced by vertebral column or backbone.

2. Presence of Nerve chord : It is hollow , tubular nerve tissue. It is situated dorsally above the nerve chord. It is later on replaced into brain and spinal chord.

3. Presence of Gill slit : It is paired lateral gill opening situated in both side of pharynx. It is respiratory opening that take part in the exchange of gases.

4. They have closed circulatory system with RBC.

5. Presence of post anal tail.

6. Presence of ventrally situated heart.

7. They are triploblastic, bilaterally symmetrical and coelomate.

HSEB notes | Difference between gram +ve and gram -ve bacteria.

The difference between gram +ve (positive) and gram -ve (negative) bacteria are as follows : 

Gram +ve bacteria	Gram –ve bacteria
1. Their cell wall is 100-200 A thick       and homogenous.	1. Their cell wall is comparatively thin i.e 170-120 A and heterogenous.
2. They do not bear fimbriae or sex pilli.	2. They bear fimbriae or sex pilli
3. Peptidoglycan consists of about     70% of the cell wall.	3. Peptidoglycan consists of about 30% of the cell wall.
4. They retain deep blue or purple colour with crystal violet and subsequently with Potassium Iodide and alcohol.	4. They retain deep blue or purple colour with crystal violet and lost colour when treated with  Potassium Iodide and alcohol.
5. Mesosome is present.	5. Mesosome is absent.
6. They do not have resistant to Lysozome or antibiotics.	6. They show resistance with Lysozome or antibiotic due to the presence of lipid rich layer.

Solanaceae | Family Description | Biology - HSEB Notes

Distribution : They are distributed widely in the temperate and tropical region. Most of the plants belonging to this family are mesophytes. They are cultivated for vegetables , as They are cultivated for vegetables , as ornamental plant etc.

Habit :Most of them are annual herbs , rarely trees.

Vegetative characters

-  Root : Tap root system with lateral branches.

-  Stem : Erect , herbaceous , aerial , branched , solid or fistular , cylindrical. In some the stem is modified into tubers as in Solanum tuberosum.

-  Leaves : Cauline ,ramal, pertiolate or sessil or sub sessile , exstipulate , simple ,ovate , margin : dentate or entire , unicostate, reticulate venation

Floral characters

-  Flowers : Ebracteate , pedicellate , complete ,actinomorphic , rarely zygomorphic ,bisexual, pentamerous , hypogynous

- Inflorescence : Cymose , generallyaxillary but sometime extra-axillary or terminal cyme

-  Calyx : Sepal - 5 , gamosepalous , hairy , campanulate , inferior, valvate aestivation

- Corolla : Petal - 5 , gamopetalous , infundibuliform or tubular , inferior , valvate aestivation,

- Androceium : Stamen - 5, polyandrous , epipetalous , alternate to petal, anther : basifixed , dithecous ,introse

- Gynoceium : Carpel - 2 , bicarpellary , syncarpous , ovary superior and obliquely placed, bilocular with many ovaries on swollen placenta , sometime tetralocular due to development of false septum , aile placentation , style simple , stigma : capitate or bilobed

-  Pollination : Cross , entomophilous

-  Fruit : A many seeded berry or capsule

-  Seed : Albuminous or endospermic which is curved or straight

HSEB botany notes | Economic importance of family Solanaceae

HSEB biology , botany notes : 

Economic importance of family Solanaceae are as follows: 

1. Vegetables : Most of the plant belonging to this family are cultivated for vegetable purpose. Some of them include Solanum tuberosum , Capsicum annum , Solanum melonfena , lycoprsicum esculentum etc. Tomoatos' is also used in making sauce.

2. Capsicum annum is used as condiment , in spices and beverage pungent.

3. Medicine : Dried leaves , stem and roots of Atropa belladona yield atropin which is relieve. Dried leaves and roots of Datura metel is used for treatment of asthama.

4. Edible fruit are obtained  from some species of this family like Rhasbari (from Physalis sp).

5. Nocotiana tobaccum is famous for chewing and for smoking but it's excess use can harm the body.

6. Ornamental purpose :  Cestrum diurnum , Cestrum , nocturnal , Cestrum elegans is used in garden as ornamental plant.

Cruciferae (Brassicaceae) | Family Description | Biology - HSEB Notes

This family comprises about 365 genera and 3250 species. 94 species of 38 genera have been reported in Nepal.

 Distribution : The family Cruciferae is cosmopolitan in distribution. Primarily, it is found in temperate zone of northern hemisphere. The plant of this family are cultivated for vegetables, oil yielding seed , ornamental purpose.

Habit : They are mostly herbs which may be annual , perennial , biennial and rarely small shrubs. The plant posses pungent sap having sulfur containing glucoside.  

Vegetative characters :

- Root : Tap root and branched. In some species , tap root is modified into napiform(Raphana      sativum) and fusiform (Brassica rapa).

- Stem : Erect , herbaceous rarely wooded , branched or unbranched , solid , cylindrical, hairy. The main stem is condensed   very much in some sepecies like Brassica rapa , Raphana sativum etc.

- Leaves : Radical , cauline , ramal, alternate , petiolate or sessile , simple , lyrate , unicostate ,      reticulate venetion , hairy.

Floral characters :

- Inflorescence : Racemose type , generally raceme or corymb or corymboseraceme.

- Flower - Ebracteate , pedicellate , complete , bisexual , actinomorphic and rarely zygomorpohic, tertramerous , cruciform , hypogynous.

- Calyx : Sepal - 4, polysepalous , arranged in two whorls 2+2, inferior , petalloid , imbricate aestivation.

- Corolla : Petal - 4 ,polypetalous, each alternating with carpel , cruciform , valvate aestivation , inferior.

-  Androcieum : Stamen - 6, arranged in two whorls 2+4,  polyandrous , tetradynomous, outer two short and inner 4 long stamen, green nectrarial gland is present at the base of stamen,  anther is dithecious, basifixed, introse.

- Gynoceium : Carpel - 2 , bicarpellary , syncarpous , ovaries : superior , unilocular in the early stage and become bilocular  due to developmebt of false septum called replum, style is short and simple , stigma : capitate.

- Pollination : Cross , entomophilous , self sometime.

- Fruit : Siliqua or Silicula.

- Seed : Small , non-endospermic with curved embryo , cotyledon is oily. 

Picture from biologydiscussion.com

HSEB botany notes | Economic importance of Family Cruciferae or Brassicaceae

The economic importance of Family Cruciferae or Brassicaceae are as follows : 

1. Vegetables : The plant belonging to family cruciferae like Brassica rapa , Raphana sativum , Brassica juncea are used as vegetables. 

2.Condiments : Seeds of plants like Brassica nigra , Brassica juncea are used as spices and condiments.

3. Fodder : The mustard cake (remain of seed after extraction of oil, leaves of some plant of family is used as fodder.

4.Oil : Oil is extracted from seed of plants like Brassica campestris, Brassica juncea . This oil is used for cooking and burning purpose.

5. Ornamental purpose : Iberis amara , Lunaria is grown as ornamental plant.

6. Medicine : The seed of candytuft is used for treatment for gout and asthma. The root of Lepidium sativum is used against syphilis.

HSEB notes Scientific name or zoological name of kingdom Animalia

The scientific or zoological name of the organic of Kingdom Animalia are as follows :

Porifera

1.Venus flower basket sponge                          -  Euplectella
2.Glass rope sponge                                          - Hyalonema
3.Bath sponge                                                   - Euspongia
4.Largest sponge                                               - Spheciospongia
5.Smallest sponge                                             - Leucosolenia

Coelenterata

1.Jellyfish                                                           - Aurelia
2.Sea anemone                                                   - Metridium

Platyhelminthis

1.Liverfluke                                                       - Fasiola hepatica
2.Tapeworm                                                      - Taenia solium

Nemathelminthes

1.Round worm                                                  - Ascaris lumbricoides

Annelida

1.Earthworm                                                     - Pheritima posthuma

2.Leech                                                             - Hirudinaria

3.Clamworm                                                     - Nerei
4.Living fossil                                                  - Polygordius

Arthopoda

1.Prawn                                                             -  Palaeomon

2.Centipede                                                       - Scolopendra
3.Milipede                                                         - Julus 

4.Cockroach                                                     - Periplaneta americana
5.Silkworm                                                       - Bombyx
6.Grasshopper                                                  - Melanopus
7.Butterfly                                                         - Pieris
8.Housefly                                                        - Musca domestica
9.Honey bee                                                      - Apis
10.Crab                                                             - Cancer
11.Water flea                                                    - Daphnia
12.Scorpion                                                      - Palamnaeus
13.Spider                                                          - Aranea

Mollusca

1.Land or garden snail                                     - Helix
2.Cuttle fish                                                     - Sepia
3.Devil fish                                                      - Octopus

Echinodermata

1.Starfish                                                        - Asterias
2.Sea cucumber (Cucumaria)                        - Holothuria
3.Sea lily                                                        -Antedon
4.Brittle star                                                   - Ophioderma
5.Sea urchin                                                   - Echinus

Chordata

1.Rohu                                                           - Labeo rohita

 2.Dog fish                                                     - Scoliodon
3. Electric fish Torpedo
4.Sea horse                                                    - Hippocampus
5.Flying fish                                                  - Exocoetus
6.Frog                                                             - Rana tigrina
7.Tree frog                                                      - Hyla
8.Toad                                                            - Bufo
9.Wall lizard                                                   - Hemidactylus
10.Garden lizard                                             - Calotes
11.Green turtle                                                - Chelone 
12.Cobra                                                         - Naja naja
13.Sparrow                                                     - Passer domesticus
14.Pigeon                                                        - Columba livia
15.Parrot                                                         - Psittacula psittacula
16.Crow                                                           - Corvus
17.Ostrich                                                        - Struthio
18.Rabbit                                                         - Oryctolagus cunicalus
19.Squirrel                                                      - Funambulus
20.Bat                                                              - Pteropus
21.Monkey                                                      - Macca
22.Tiger                                                          - Panthera tigris
23.Human                                                       - Homo sapeins sapeins
24.Lion                                                           - Panthera leo
25.Kangaroo                                                   - Marcopus
26.Elephant                                                     - Elephas maximum
27.Gorilla                                                        - Gorilla gorilla
28.Dog                                                            - Canis familiaris
29.Horse                                                          - Eqqus eqqus

HSEB zoology notes | General characteristic of Aves

The general characteristic of Aves are : 

1. The body of aves is covered by feather and they are adapted to for aerial mode of life.

2. Body form : Their body is streamed lined and divided into head, tail ,trunk and neck. Head is small and round , neck is flexible and monocondylic (can rotate 360 degree) and tail is short and stumpy.

3. Locomotion : Locomotion is aves is served by two pair of limbs. fore limbs are modified into wings for flying and hind limb to support  the body, for piercing mechanism , swimming and walking purpose. There are four fingers. 3 fingers are directed forward and one is directed backward called hallux. Thus it shows bipedal.

4. Respiration : They respire through spongy and inelastic lungs. It consists of many air sac.

5. Nervous System : Their consists of 12 pair of cranial nerve.

6. To reduce their body weight their bone is hallow , pneumatic , porous without bone marrow.

7. Skin : Their skin is dry and without gland. However oil gland or peer gland is which is present at the root of tail secrete oil to soften and greasy the feathers.

8. Excretion : They perform excretion by metanephric kidney. Urinary bladder is absent. They are ureotelic(those who excrete uric acid) .

9. Reproduction System : Sexes are separate in them. Sexual dimorphism is usually distinct. Male have paired testes. Female have only one ovary.

10. Fertilization is internal preceded by courtship (attracting female) and copulation and they are oviparous (egg laying) and development is direct.

HSEB zoology notes | General characteristics of Reptile

The general characteristics of reptile are as follows:

     1.       Habitat : They are mostly terrestrial and some are aquatic. They are cold blooded (poikilothermic) animal.

    2.       Body form : Their body is elongated and cylindrical and divided into head ,trunk , neck and tail. Skin is dry , rough and non-glandular. It is covered by scales or bone plates. 

    3.  Locomotion: Locomotion in amphibian is carried out by two pair of pentadactyle limbs. Horny claws are present aquatic form, digits in terrestrial form.

   4.       Respiration : They respire through lungs. In turtle, gaseous exchange take place through cloaca.

   5.       Nervous System : They have 12 pair of carnial nerve arising from brain.

   6.       Reproduction : Sexes are separate and they are oviparous. Eggs are covered by CaCO3.

Eg : Hemidactylus (wall lizard) , turtle etc

HSEB zoology notes | General characteristics of Amphibians

    HSEB notes

    The general characteristics of Amphibian are as follows:

1.  Habitat: They live both in land and water. They are cold blooded (poikilothermic) animal.

     2.       Sleeping period: They undergo hibernation (winter sleep) and aestivation (summer sleep) period during unfavorable condition.

     3.     Body : Their body is cylindrical and divided into head trunk and mobile neck. Their head is triangular and bears pair of eye, external nosestril and tympanum. Eyes are protected by nictitating membrame.

  

    4.     Locomotion: It takes place by pentadactyle fore and hind limbs. Claws are absent. Fore limbs has 4 fingers and hind limb has  5 fingers with webbed and longer toes.

  

    5.     Nervous System: They have 12 pair of carnial nerve arising from brain.

7

    6.       Reproduction system :  Sexes are separate in them(diocious) .

    7.    Development is indirect and fertilization is external.

    Eg : Hyla, Rana(frog) , Toad(bufo) etc.

HSEB zoology notes | General characteristic of Pisces

The general characteristics of Pisces are as follows :

1.  Habitat : They are completely aquatic found in marine or freshwater. They are cold blooded (poikilothermic) animals.

2.  Body form : They have streamlined body or boat shaped and laterally compressed. Body is covered by cycloid or placetoid scales.

3.  Locomotion : Locomotion in Pisces is performed by paired fins (pelvic, pectorial fins) and unpaired fins (anal , dorsal , caudal fins).

4. Respiration : They respire through gills. Gills may or may not be covered by operculum.

5. Swim bladder may or may not be present and they two chambered heart.

6. Reproduction system : Sexes are separate in them (diocoius) and some show sexual dimorphism like cartilaginous fish and some don't like bony fish. Those who show sexual dimorphism have clasper for transferring sperm to female genital tract.

7. Development is direct and fertilization in Pisces is both internal and external.

HSEB zoology notes | Difference between cartilaginous fish and bony fish

The difference between Chondrichthyes (cartilaginous fish) and Osteichthyes (bony fish) are as follows: 

Chondrichthyes (cartilaginous fish)	Osteichthyes   (bony fish)
1.       They are marine.	They are both marine and fresh water.
2.       Swim bladder is absent.	Swim bladder is present.
3.     Endoskeletion is cartilaginous.
4.   Endoskeletion is bony.	No operculum. Spiracles are present.
5.  Gills are enclosed by operculum.	Mouth is at the presnt at the ventral region.
6.  Mouth is present at the terminal region of the     body.	Fertilization is internal.
7. Sexual dimorphism is distinct. They have clasper for transferring sperm to female genital tract. eg : Scoliodon , Torpedo (electric fish) etc	Sexual dimorphism is not distinct. Clasper are absent. eg : Labeo (rohu) ,  Exocoetus (flying fish) etc