Cockroach(1) Flashcards
give the taxonomy of a cockroach
Phylum- Arthropoda (jointed appendages and and chitinous skeleton)
Class - Insecta (3 pairs of jointed legs)
Order- Dictyoptera
Genus- Periplaneta
Species- americana
explain some features about cockroach
Cockroach is omnivorous, cursorial (fast runner) and
nocturnal animal. It also exhibits Cannabalism.
Parental Care does not found in Cockroach.
Cockroach chromosome no. = 34.
how are the three segments of coackroach divided
Body of cockroach is divided in to 3 parts called →Tegmata. They are-
HEAD, THORAX AND ABDOMEN.
In Embryo stage head (6) + thorax (3) + abdomen(11) = 20 segments
In Adult stage head (1) + thorax (3) + abdomen(10) =14 segments
Sclerites of head fused fully to form head capsule (formed by the
fusion 6 segments).
name of different chitinous plates
Exoskeleton of chitin plates occurred in each segment. Chitin plates called
“sclerites”.
Sclerites of dorsal side - tergum or tergite.
Sclerites of ventral side - sternum or sternite.
Sclerites of lateral side - pleurons or pleurites.
Sclerites joined each other by “membrane” called “articular or arthrodial
membrane.”
explain the mouth parts of the cockroach
A cavity formed due to presence of mouth parts called pre-oral
cavity. 5 types of mouth parts-
Labrum or Upper Lip - Dorsally overhangs the mouth. Holds the
food for feeding & has gustato-receptor (tasting).
- Mandibles or Jaw (1-pair) - They form the lateral wall of pre-oral
cavity. Grinding of food. - First maxillae (1-pair) - Putting the food in oral cavity. Also used
as brush to clean antenna and wings. - Second Maxillae or Labium or lower lip - It forms the floor of
pre-oral cavity and covers ventral side. - Hypopharynx or lingua or tongue - Non-chitinous flexible
structure. Common salivary duct opens at the base.
where are the legs present and what are their parts?
5 segments are present in legs known as Podomeres
(i) coxa
(ii) trochanter
(iii) femur
(iv)tibia
(v) tarsus
(vi) pretarsus
(vii) claw
what are th 2 types of wings
Forewing or Mesothoracic
wing or Elytra or Tegmina-
long, narrow, thick, leathery,
dark, opaque, covers body.
Hindwing or Metathoracic
wings- small, broad, thin,
membranous, transparent,
helpful in flight
what are the abdomen
10 segments are present in male and female.
10th tergum bowl shaped and bifurcated and has 1 pair
”Anal cerci - Sound receptor” bear in both male and
female.
7th tergum is largest in male and female and covers 8th
and 9th tergites.
Stink gland present in between 5th and 6th tergum its
smell repels enemies.
Sternum : In male- 9 sternum and in female- 7 sternum.
Anal or caudal style – 1 pair from 9th sternum only in male,
non segmented structures → Help in copulation.
what is haemocoel
Also known as Haemocoel
Haemocoel is not true coelom
All arthopodes are true coelomates but coelom is highly
reduced and found only in the form of the cavity of gonads
called Gonocoel.
Lagre fat bodies (corpora adiposa) present in haemocoel
Fat bodies are analogous to liver of higher animals
what are the salivary glands
Consists of salivary glands and alimentary canal
Salivary glands secretes → Saliva
which contain amylase, cellulase,
chitinase.
It is attached to crop
3 parts of the alimentary canal
A) FOREGUT-Ectodermal in origin- cuticle layer present
B) MIDGUT-Endodermal in origin- cuticle layer absent
C) HINDGUT-Ectodermal in origin- cuticle layer present
foregut parts:
(i)- gizzard: helps in grinding of food with cuticular teeth/ cavity is called armarium
(ii) sieve platE: filtering of food due to cuticular hair
(iii)stomodeal valve: prevent backflow of blood/ junction of fore and midgut
foregut is formed by invagination of body wall. the cuticle is present in the inner wall/
midgut or mesenteron parts:
(i) Anterior top part: cardia- secrete peritropic memebrane m/o glyocgen and protein beacsue midgut do not have cuticle layer
stomodeoal valve opens onto cardia into the midgut
bacetria and symbiotic protozoa present whichhelp in the digestion
mesenteron is muscular
Hepatic caeca is derives from mesenteron
hind gut parts
(a) 100-150 yellow colored thin tubules attached at the junction of
hind gut and mid gut called “Malpighian tubules” → Removal
of excretory products from haemolymph)
(b) Hind gut has three parts :
(i) Ileum - Its wall is thin and internally folded. Its cuticle bears
minute spines, which serve to break the peritrophic
membrane.
(ii) Colon - Longest and broader part
(iii) Rectum - Last part, oval shaped. Its wall has 6 folds - called
Rectal papillae which absorb water.
Anus - At the end of 10th abdominal segment.
wat are some other excretory structure except malphigiain tubules
Urate cell : Storage excretion
Nephrocytes and fat bodies: Storage excretion
Body wall : Absorbs excretory materials from Haemocoel and store in
cuticle. Then at the time of moulting excretory substances and cuticle
separate out from body
Uricose glands : These help in excretion in male cockroach.