Biology: STRUCTURAL ORGANISATION IN ANIMALS

STRUCTURAL ORGANISATION IN ANIMALS

Tissues – a group of similar cells which perform same function together.

Types of tissues are – Epithelial tissue, Connective tissues, Muscular tissues and Nervous tissues.

1.Epithelial tissues:

 

·         Covers external surface and lines internal surface

·         Three specialized junctions are tight junction, adhering junction and gap junction

·         Non cellular basement membrane

·         No blood vessels

·         Receives nutrients from underlying connective tissues

Classification :

a)Simple epithelial  (one layer) –

·         Squamous epithelium

·         Cuboidal epithelium

·         Columnar epithelium

·         Pseudo stratified epithelium

b)Compound epithelium  (many strata) –

·         Stratified compound epithelium (squamous, cuboidal, columnar)

·         Transitional epithelium (urinary bladder)

2.Muscular tissues :

·         Striated muscle / Striated muscle / Voluntary muscle

·         Unstriated muscle / Smooth muscle / Involuntary muscle

·         Cardiac muscle (heart)

3.Neural tissue – longest cell – neuron

Structure of neuron: Dentrite – Cyton – Axon with myelinated sheath with node of ranvier – axon ending


Organ and organ system:

Cockroach

Class: insect

Phylum: arthropoda

Morphology:

·         1/4   -3  inches

·         nocturnal omnivorous

·         body- head, thorax and abdomen

·         body is covered with chitinous exoskeleton with hardened plates. Plates are called  sclerites (tergites and sternites ) connected by arthrodial membrane.

·         Compound eyes. Antennae, bitting and chewing mouth parts.

·         Mouth part consists of a labrum ( upper lip ), a pair of mandible, a pair of maxillae and a

·         Labium ( lower lip ) and a tongue called hypopharynx.

·         Throax  consists of three parts- prothorax, mesothorax, metathorax ( each has a pair of legs )

Anatomy :

 

a)Digestive system. Mouth-oesophagus-crop-gizzard-hepatic caecae- midgut-hind gut- rectum-anus

b)Circulatory system. Open blood vascular system- blood (haemolymph) - Pumped in to space (haemo coel ) blood (plasma + haemocytes ) heart is elongated muscular tube in dorsal line, heart is opening called ostia (blood enters pumped anteroirly.

c)Respiratory system.  Tracheary  system. (net work of trachea) - External opening called spiracles – trachea – tracheoles – blood.

d)Excretory system. Malphigian tubules - Collect uric acid -  Uricotelic – in  addition fat bodies, nephrocytes and Urecose glands.

e)Nervous system. Ganglian - 3 pair in thorax and 6 pair in abdomen.

f)Sense organs. Antennae, compound eyes, maxillary palps, labial palps and  anal cerci - Eye is compound, made of 2000 ommatidium (mosaic vision)

g)Reproductive system. 

·         Male. Testes. (4-6 ) vas deferens- seminal vesicle - ejaculatory duct.

·         Female- ovaries (2-6) oviduct- vagina – genital chamber - fertilized egg – ootheae ( 9-10 oothecae) development is paurometabolous, devevelopmrnt Is through nymphal stage. It looks like adult grows of moulting 13 times.