1. Amphibians have two auricles and one ventricle and no inter ventricular septum whereas reptiles except crocodiles have two auricles and one ventricle and an incomplete inter ventricular septum.
2. Thus mixing of oxygenated and deoxygenated blood takes place in the ventricles.
3. This type of circulation is called incomplete double circulation.

1. Chymotrypsin occurs in an inactive form called chymotrypsinogen which is activated by Trypsin.
2. Chymotrypsin hydrolyses peptide bonds associated with specific amino acid.
3. It is a pancreatic enzyme and is proteolytic in nature. It plays a role in digestion of food in the duodenum.

(i) Animals exclusively live in marine.
(ii) They lead burrowing mode of life.
(iii) They resemble fishes.
(iv) Presence of notochord, dorsal tubular nerve cord and pharyngeal gill slits are persistant.
(v) Closed circulatory system is found lacking of heart.
(vi) Protonephridia aid in excretion.
(vii) Unisexual and fertilization is external.
(viii) Development is indirect.
Eg: Branchio stoma (Amphioxus or Lancelet).

1. The Hemichordates have both invertebrate and vertebrate characters.
2. They are worm like, tubicolous animals.
3. They are bilaterally symmetrical, triploblastic coelomate animals with organ system level of organisation.
4. They body is divided into proboscis, collar and trunk.
5. They are ciliary feeders.
6. Circulatory system is simple and open.
7. Excretion is by a single proboscis gland or glomerulus situated in the proboscises.
8. Sexes are separate.
9. Fertilization is external.
10. Development is indirect with tornaria larva. e.g., Balanoglossus.

1. These are bilaterally symmetrical, triploblastic, schizocoelomate, segmented animals.
2. They have organ system grade of organization.
3. They have jointed appendages.
4. Body is covered by chitinous exoskeleton. The body is divided into head, thorax, and abdomen.
5. Body cavity is filled with colorless blood. It is called hemocoel.
6. Respiratory organs are gills, book gills, book lungs, trachea.
7. Open-type circulation is seen.
8. Sense organs are present.
9. Fertilization is internal. e.g., humulus, insects.

ALIS: Automated leaf hopper identification system.
DAISY: Digital automated identification system.
ABIS: Automatic Bee identification system.
SPIDA: Species Identified Automatically (spiders, wasp, bee wing characters)
Draw wing: Honeybee wing identification

Herbarium and Botanical garden may be used as tools for the plant taxonomy. Museum, Taxonomical keys and Zoological parks are Classical tools for animal studies. Field visits, survey, identification, classification, preservation and documentation are the important components of taxonomical tools.

The body wall of the earthworm is very moist, thin, soft, skinny, elastic and consists of the cuticle, epidermis, muscles and coelomic epithelium. The epidermis consists of supporting cells, gland cells, basal cells and sensory cells. A spacious body cavity called the coelom is seen between the alimentary canal and the body wall. The coelom contains the coelomic fluid and serves as a hydrostatic skeleton, in which the coelomocytes are known to playa major role in regeneration, immunity and wound healing. The coelomic fluid of the earthworm is milky, which consits of granulocytes or eleocytes, amoebocytes mucocytes and alkaline, leucocytes.

Frontal lobe - Behaviour, Intelligence, Memory, Movement
Temporal lobe - Speech, Hearing, Memory

A- Rod cell, B- Cone cell
A- Rods are photoreceptor cells responsible for vision in dim light in the human eye.
B- The cones are photoreceptor cells responsible for colour vision in the human eye

Lobes of cerebral hemisphere
A- Parietal lobe
B- Cerebellum
C- Frontal lobe
D- Temporal lobe

Melanocytes are the cells responsible for-producing the skin pigment, melanin, which gives skin its colour and protects it from the sun's UV rays.

The parietal cells in the wall of the stomach secrete an intrinsic factor called castle's intrinsic factor. It is responsible for the absorption of vitamin B₁₂.

1. Elastic fibres allow the artery to stretch and recoil as blood passes through it.
2. Arteries closer to the heart experience more pressure than arteries further away from the heart.
3. Therefore arteries close to the heart have more elastic fibres in their walls to cope with high pressure of blood coming from the heart.

Mouth parts of cockroach
A- Maxilla
B- Labium

1. White fat is said to be 'Bad fat' since it hoards calories and contributes to obesity.
2. Brown fat is said to be 'good fat' which helps burn calories.
3. Research has proved that this conversion of white fat to brown fat is possible, so that calories will be burnt and accumulation of fat leading to obesity and related health issues can be avoided.

a) Cockroach    -Chitinous outer covering exoskeleton
b) Human being - Epidermal hair, nails
c) Garden lizard - Epidermal scales
d) Snail              - Calcareous Shell
e) Dog                - Epidermal hair, nails, hoofs.

1. All chordates possess a notochord.
2. All chordates possess a dorsal, hollow, nerve cord.
3. All chordates possess pharyngeal gill clefts in some stage of their life cycle.
4. Possess a post-anal tail.

Saving Endangered Species:
1. The greatest threat to survival is destruction of habitat. It is important to conserve the habitat or the special places where the species live.
2. The animals must have places to find food, shelter, and care for their young ones.
3. Setting up Zoological parks and nature reserves will help to conserve the species.
4. Mutual agreement between countries can help to save forests and species in coastal waters.
5. Scientists are setting up gene banks to conserve animals of a species.
6. Several organisations are also working for the protection of endangered species.
7. Hot spots/areas with high biodiversity must be protected from human intervention to conserve the animal and plant species.

1. Purple pig-nosed Frog was discovered in the Western Ghats.
2. It has shiny purple skin and spends its entire adult life underground.
3. It is called Bhupathy's purple frog by the scientists in memory of Subramaniam Bhupathy a respectable herpetologist who lost his life is the Western Ghats.

The naming of an organism is followed by the three words 1^st word is genus (starts with the capital letter) 2^nd word is species (starts with the small letter) and 3^rd word is sub-species (starts with the small letter).