Register Login

Introduction to kingdom animalia

Subject: Biology

Find Your Query

Overview

An animal kingdom is a group of many-celled organisms which cannot manufacture their own food. This note contains detail information about its habitat, symmetry, body plan, excretion, nutrition, fertilization, development etc
Introduction to kingdom animalia

An animal kingdom is a group of many-celled organisms which cannot manufacture their own food.

Habit

Animals may be motile, sedentary or sessile. They may occur singly, solitary, gregarious or colonial. They show a great diversity in heterotrophic modes i.e. herbivores, carnivores, omnivores, parasite, predator, sanguivorous, coprophagous.

Habitat

Daphnia
source:www.youtube.com
fig:Daphnia in water
Aquatic:

Live in water. On the basis of distribution in water, aquatic animals are of following types:

Planktons: Daphnia

Nectons: Fishes

Benthes: Sycon

Terrestrial:

Live on land. On the basis of distribution, it is of following types:

Subterranean: Earthworm

Curssosial: Cockroach

Arboreal: Monkey

Aerial: Bird

Cellularity

Unicellular: Protozoa

Multicellular: remaining all metazoans from protozoa to chordata.

Body layer

  1. Diploblastic: Having two germ layer i.e. ectoderm and endoderm.eg. protozoa, Porifera, Coelenterata.
  2. Triploblastic: Having three germ layer i.e. ectomeso, ectoderm, endoderm.eg. Platyhelminthes to Chordata.

Protozoa
source:www.abpischools.org.uk
fig:Protozoa

Level of body organisation

Protoplasmic: Protozoa

Cellular: Porifera

Tissue: Coelenterata

Organ system: Platyhelminthes to Chordata

Body symmetry

a) Asymmetrical body:

The body which cannot be divided into two equal halves from any plane is called an asymmetrical body. eg: Amoeba, Paramecium.

b) Symmetrical body:
  • The body which can be divided into two equal halves from one or more than one planes is known as a symmetrical body.Body symmetry is of following types:
  • Spherical or universal symmetry: The body which can be divided into two equal halves from more than one plane passing through the centre of the body. eg: Volvox.
  • Radial symmetry: The body can be divided into two equal halves from many radial planes passing through the central axis.eg; starfish.
  • Bilateral symmetry: The body can be divided into two equal opposite halves from only one median longitudinal plane. One-half of the body is a mirror image of another. eg; butterfly.
Diagram showing body symmetry A- Bilateral symmetry, B- Radial symmetry, C- Asymmetry.
source:www.kullabs.com
fig:Diagram showing body symmetry A- Bilateral symmetry, B-Radial symmetry, C-Asymmetry.

Coelom

The body cavity found in between body wall and gut wall is called coelom. Coelom is of following types:

  1. True coelom:The body cavity found in between body wall and the gut wall formed by splitting of the mesodermal layer is called true coelom. eg; annelids and higher animals.
  2. Pseudocoelom: Body cavity filled with muscles. eg; nematodes.
  3. Haemocoelom: Body cavity filled with blood. eg; Arthropoda and Molluscans.
  4. Acoelom: Body without any cavity. eg; Poriferan, Coelenterataand Platyhelminthes.
Different types of coelom in animals
source:www.kullabs.com
fig:Different types of coelom in animals

Body plan

a) Cell aggregate form: If the elementary canal is absent than such body is called cell aggregate form. eg; Sycon.

b) Blind sac form: The alimentary canal has only one opening called mouth for both ingestion and egestion. eg.Hydra.

c ) Tube form: If elementary canal has both mouth for ingestion and anus for egestion it is called tube form.It has two types:

  • Protostromous: Mouth develops earlier than the anus. eg; roundworm, earthworm, arthropods, molluscans.
  • Deuterostromous: Anus develops earlier than the mouth. eg; Echinodermata and Chordata.

Nutrition

Holozoic: Animals

Holophytic: Green plants

Saprozoic: Earthworm

Saprophytic: Fungus

Parasite: Liver fluke

Mixotrophic: Euglena

Digestion

Intracellular: Protozoa

Extracellular: All higher animals

Respiration

Anaerobic: In the absence of oxygen. eg; protozoans.

Aerobic: In the presence of oxygen.eg; higher animals.

Circulation

  1. Open type: Blood flows in a body cavity. eg; Arthropods and Molluscans.
  2. Close type: Blood flows within blood vessels. eg; Human

Excretion

Contractile vacuole: Protozoa

Flame cells: Helminthes

Malphigian tubules: Arthropods

Nephridia: Annelids

Kidney: Higher vertebrates

Reproduction

Asexual

Sexual

  • Hermaphrodite or monoecious or bisexual. eg; earthworm
  • Unisexual or Dioecious: eg; Human
  • Sexual dimorphism: Male and female individuals can be distinguished by external features. eg; human

Fertilization

External: frog

Internal: Human

Development

  1. Direct development: Without larval stage. eg; human
  2. Indirect development: With larval stage. eg; insects
Things to remember
  • An animal kingdom is a group of many-celled organisms which cannot manufacture their own food.
  • If elementary canal has both mouth for ingestion and anus for egestion it is called tube form.
  • If the elementary canal is absent than such body is called cell aggregate form. 
  • The body cavity found in between body wall and the gut wall formed by splitting of the mesodermal layer is called true coelom. eg; annelids and higher animals.
  • The body which can be divided into two equal halves from one or more than one planes is known as a symmetrical body.

 

  • It includes every relationship which established among the people.
  • There can be more than one community in a society. Community smaller than society.
  • It is a network of social relationships which cannot see or touched.
  • common interests and common objectives are not necessary for society.

© 2019-20 Kullabs. All Rights Reserved.