Frog morphology and anatomy : Frog morphology and anatomy Frogs are amphibians in the order Anura (meaning "tail-less", from Greek an-, without + oura, tail).
Formerly referred to as Salientia (Latin salere (salio), "to jump").
Most frogs are characterized by a short body, webbed digits (fingers or toes), protruding eyes and the absence of a tail.
Slide 2 :
Slide 3 :
Slide 4 :
Slide 5 :
Slide 6 :
Slide 7 :
Slide 8 :
Slide 9 :
Slide 10 :
Slide 11 : Cockroaches are insects of the order Blattaria or Blattodea, of which about 30 species out of 4500 total are associated with human habitations. About four species are well known as pests.
Among the best-known pest species are the American cockroach, Periplaneta americana, which is about 30 millimetres (1.2 in) long, the German cockroach, Blattella germanica, about 15 millimetres (0.59 in) long, the Asian cockroach, Blattella asahinai, also about 15 millimetres (0.59 in) in length, and the Oriental cockroach, Blatta orientalis, about 25 millimetres (0.98 in).
Slide 12 :
Slide 13 :
Slide 14 :
Slide 15 :
Slide 16 : ESOPHAGUS: A cockroach esophagus (a fancy word for throat) isn't as long as a human's, but it gets the job done. Food travels from the mouth, through the esophagus to the stomach. CROP: The crop is a section at the end of the esophagus used to store food for a while. If a cockroach doesn't chew its food properly, a second set of teeth in its digestive tract, also called a gizzard, gives it another chance.
GASTRIC CAECEA: If cockroaches couldn't digest their food, they'd explode! The gastric caecea are little sacks inside a cockroach that keep germs and enzymes available to help a cockroach digest its food.
MIDGUT: The middle part of the intestine where the cockroach absorbs nutrients is called the midgut. MALPIGHIAN TUBULES: You say po-tay-toe, I say po-tah-to. You say malpighian tubules, I say cockroach kidney. Either way, it's the same thing! Malpighian tubules clean waste out of the blood. And when they do their job they wiggle like snakes in the "blood" that sloshes around the cockroach's digestive tract.
COLON: Cockroaches not only have a colon, but a rectum, too! Hooray! Special glands in the rectum reabsorb water used during digestion, leaving behind excrement (poop).
Slide 17 :
Slide 18 :
Slide 19 :
Slide 20 :
Slide 21 : Respiratory System: The respiratory system consists of a network of trachea, that open through 10 pairs of small holes called spiracles present on the lateral side of the body. Thin branching tubes (tracheal tubes subdivided into tracheoles) carry oxygen from the air to all the parts. The opening of the spiracles is regulated by the sphincters. Exchange of gases take place at the tracheoles by diffusion
Slide 22 : Blood Vascular System: Blood vascular system of cockroach is an open type. Blood vessels are poorly developed and open into space (haemocoel). Visceral organs located in the haemocoel are bathed in blood (haemolymph). The haemolymph is composed of colourless plasma and haemocytes. Heart of cockroach consists of elongated muscular tube lying along mid dorsal line of thorax and abdomen. It is differentiated into funnel shaped chambers with ostia on either side. Blood from sinuses enter heart through ostia and is pumped anteriorly to sinuses again.
Slide 23 : Male Reproductive System: Male reproductive system consists of a pair of testes lying one on each lateral side in the 4th -6th abdominal segments. From each testis arises a thin vas deferens, which opens into ejaculatory duct through seminal vesicle. The ejaculatory duct opens into male gonopore situated ventral to anus. A characteristic mushroomshaped gland is present in the 6th-7th abdominal segments which functions as an accessory reproductive gland. The external genitalia are represented by male gonapophysis or phallomere (chitinous asymmetrical structures, surrounding the male gonopore). The sperms are stored in the seminal vesicles and are glued together in the form of bundles called spermatophores which are discharged during copulation.
Female Reproductive System: The female reproductive sysytem consists of two large ovaries, lying laterally in the 2nd – 6th abdominal segments. Each ovary is formed of a group of eight ovarian tubules or ovarioles, containing a chain of developing ova. Oviducts of each ovary unite into a single median oviduct (also called vagina) which opens into the genital chamber. A pair of spermatheca is present in the 6th segment which opens into the genital chamber.
Fertilization: Sperms are transferred through spermatophores. Their fertilised eggs are encased in capsules called oothecae. Ootheca is a dark reddish to blackish brown capsule, about 3/8" (8 mm) long. They are dropped or glued to a suitable surface, usually in a crack or crevice of high relative humidity near a food source. On an average, females produce 9-10 oothecae, each containing 14-16 eggs. The development of P. Americana is paurometabolous, meaning there is development through nymphal stage. The nymphs look very much like adults. The nymph grows by moulting about 13 times to reach the adult form. The next to last nymphal stage has wing pads but only adult cockroaches have wings.