INTRODUCTION/ DEFINITIONS.
Biodiversity refers to varieties of animals and plants.
Eukaryotes are organisms which have cells with well defined nucleus.
Autotrophs are organisms producing their own food.
Saprophytic are organisms that use decaying organic materials as food.
The systematic grouping of organisms into categories is called as classification.It helps in bringing out similarities and dissimilarities among the organisms.
Notochord is a long rod like support structure that runs along the back.
Organisms are unicellular in protista and multicellular in others.
A cell wall is absent in animals. Cell wall contains chitin in fungi and cellulose in plants.
Plastids occur in plant cells.
Perpetuate means the continuation of species by reproduction.
Cell structure is used as a criterion for placing an organism in monera or protista.
A cell wall generally containing cellulose occurs around cells.
Central Vacuole is a mature cell commonly possesses a single large central vacuole.
Gymnosperms are plants that bear naked seeds.
Vertebrata is divided into five classes—pisces, amphibia, reptilia, aves and mammalia
Monocots are plants which bear single cotyledon in their seeds. Dicots are the plants which bear two cotyledons in their seeds.
All Algae possess chlorophyll and have autotrophic mode of nutrition and their cell wall made of cellulose.
All Fungi lack chlorophyll, have heterotrophic mode of nutrition and their cell wall made of chitin.
Paramecium possesses two types of nuclei, micronucleus and macronucleus.
Bilateral symmetry means body can be divided into two exact halves from one plane only.
Radial symmetry means body can be divided into equal halves from any plane.
Phylum Echinodermata has organisms which have a spiny skin and water vascular system
Thallophyta, Bryophyla and Pteridophyta are considered as cryptogams
Bryophytes are called as ‘amphibians of plant kingdom’ because they live in moist, damp places in order to get water from soil. They are dependent on water for sexual reproduction.
Presence of hollow bones is an adaptation in birds which helps them to keep low body weight which is helpful in flight.
Lichen is formed by symboitic association between an algae and a fungus.
External ears occur in mammals.Mammals generally show vivipary or give birth to young ones.
Some plastids possess photosynthesis pigments. They are called chloroplasts.