1) What is classification ? Why is it necessary?
Answer :-
Classification:- The systematic arrangement of properly identified and classified organisms is called classification.
NEED:
1) There are millions of plants and organisms inworld.They varies in shape,size,structure and habitat.
2) To study different kinds of plants and animals ,they are classified into convenient groups.
3) They are classified according to their similarities , differences and evolutionary relationship.
2) State Aims of classification:
1) It helps us to identify the organisms by a definite scheme.
2) It reveals the varying degree of resemblances(similarities) and differences among organisms.
3) It provide framework for the mental storage of vast information.
4) The modern classification reveals the evolutionary relation of origin of organisms.
3) Define Taxonomy ? Describe objectives or significance of taxonomy.
Answer
Taxonomy :- (Taxa -arrangement norms - rules)
It is branch of Biology which deals with the study of collection , identification , nomenclature classification of organisms or plants.
When it is concern with plants it is called systematic Botany.
When it is concern with animals it is called systematic Zoology.
Significance:
1) To understand the characters of plants and identify the plants.
2) To fix scientific name definite to plants which are universally accepted.
3) To classify the plants by putting them in definite groups and subgroups.
4) To understand the phylogenetic relationship of the plants with respect to other groups.
4) Define Taxon and category with example.
Answer:
1) Taxon :- Ti is a group of organisms in classification example dicotyledons, monocotyledons, phenerogamas, etc.
2) Category :- Is a rank or level of taxon in classification.
Example :Species -lower rank, kingdom - highest rank spices and kingdom are category.
3) Species , genus , family order, class, division, kingdom are the categories or rank in the hierarchy.
5) Describe different units of classification or category in classification.
Answer:-
The different units of classification are as follows :-
Species , genus, family , order ,class , division, kingdom.
I) Species: -
1) The species is the smallest unit of classification.
2) It is a group of interacting and interbreeding individuals or organisms and breed truly to produce fertile offspring.
3) All species of plants are supposed to have been derived from a common ancestor.
4) Example All Banyan trees from one species i.e. benghalensis .
All rubber trees from one species i.e. elastica.
Peepul tree from another species i.e religousa.
II) Genus :-
1) The genus is a unit of classification higher than species.
2) The genus is a group of related species which shows similarities in their reproductive structure and differs in their vegetative structure.
3) Example :- Banyan tree and peepul are two different species belonging to the same genus ficus.
III) Family:-
1) It is unit of classification higher than genus .
2) The family is collection of genera showing similar reproductive characters.
3) Example :- Hibiscus and Ceda are two different genera showing similarities in reproductive characters belongs to their same family Malvacae
IV) Order :-
1) It is unit of classification higher than family .
2) Order includes closely related families.
3) For example family Malvacae and Tiliacae belongs to the same order Malvales.
V) Class:-
1) It is unit of classification higher than order.
2) Class includes all sub-classes.
3) For example Class dicotyledons consist of sub-classes like polypetalae ,gamopetalae , petalae.
VI) Division/ Phylum (for animals):-
1) The division or phylum is the largest unit of classification .
2) The division consists of closely related classes.
3) example Division angiosperms includes classes like dicot and monocot.
VII) Kingdom :-
1) It is the highest classification.
6) What is Hierarchical level of class and explain with suitable example.
Answer:-
1) Hierarchy means a group of organisms ranked one above the other.
2) Species , genus, family , order , series, class , division, kingdom.are the categories with their taxon - called hierarchical level of classification.
3) Thus according to Hierarchical level of classification the common Hibiscus plant is classified as below:-
Kingdom - Plantae
Division - Phenerogams
Sub-division - Angiospermae
Class - Dicotelydonae
Sub-class - Polypetalae
Series - Thalamiflorae
Order - Malvales
Family - Malvacae
Genus - Hibiscus
Species - Rosa - sinenansis
7) Write a note on Binomial nomenclature.
Answer :-
1) Nomenclature is the process of giving definite and scientific names to the plants.This system was proposed by Carls Linnaeus.
2) According to this system every organisms are given scientific name consists of two parts.
3) The first part of the name indicate the genus
The second part indicate the species.
4) Generic name is always noun and begins with capital letter while the specific name is an adjective and begins with small initial letter.
5) Example :- Mangifera indica is scientific name of mango plant .In this name Mangifera indicate the genus while indica indicate the species.
8)Earthworm Characteristics:
It can be divided in three parts :
1.Structural Characteristics
2.Physiological Characteristics
3.Behavioral Characteristics
Earthworms help to fertilise the soil by bringing nutrients closer to the surface.
1.Structural Characteristics:
1.An earthworm's body is streamlined and every segment contains a number of bristles called setae.
2.The streamlined shape helps the earthworm travel through soil, and the bristles improve grip if the soil is wet.
3.Circular muscles surround every segment of an earthworm's body.
4.These muscles work alongside another group of muscles running down its entire body to help the earthworm move.
2.Physiological Characteristics:
1.Some earthworm characteristics have evolved to help it regulate its bodily functions, like breathing, and protect itself, such as by excreting chemicals.
2.Many earthworms release mucus to help them move more smoothly through soil.
3.To survive changing environmental conditions, like hot or dry soil, an earthworm sometimes goes through diapause or hibernation.
4.It becomes inactive, travels deeper into the soil, rolls itself into a tight ball, releases protective mucus, and its metabolic rate drops to lower water loss.
5.The earthworm stays like this until its environment becomes more habitable.
3.Behavioral Characteristics:
1.An earthworm can't see or hear, but it is sensitive to vibration and light.
2.Most species stay in soil, burrows or piles of leaves during daylight and on the surface of the ground during the night and early morning.
3.An earthworm absorbs and loses moisture through its skin and migrates or reproduces when the ground is wet with dew.
4.An earthworm can live under submerged conditions if the oxygen content of the water is high enough, but it moves to the surface to avoid suffocation when soil is extremely wet.
5.An earthworm is a hermaphrodite, meaning it has both female and male reproductive systems. Mating earthworms exchange sperm by lying side by side.
