The skin of leeches is permeable. If salt is added, it creates an osmotic pressure. Water is pulled out from the body of leeches. It can lead to dehydration. Thus leeches immediately fall off when salt is applied.

Male Reproductive system
(i) Male reproductive system of rabbit consists of a pair of testes which are ovoid in shape.
(ii) Testes are enclosed by scrotal sacs in the abdominal cavity
(iii) Each testis consists of numerous fine tubules called seminiferous tubules
(iv) This network of tubules lead into a coiled tubule called epididymis, which lead into the sperm duct called vas deferens.
(v) Below the urinary bladder is the urethra. Vas deferens joins the urethra.
(vi) Urethra runs backward and passes into the penis.
(vii) There are three accessory glands namely prostate gland, cowper's gland and perineal gland. Their secretions are involved in reproduction.

(i) Canines are absent.
(ii) Hence, a gap is seen between the incisors and premolars.
(iii) This is called diastema.
(iv) It helps in mastication and chewing of food in herbivorous animals.

The leech, while making incision on the skin it also injects an anaesthetic substance that prevents the host from feeling the bite.

(i) The female reproductive system of rabbit consists of a pair of ovaries which are small ovoid structures. They are located behind the kidneys in the abdominal cavity.
(ii) A pair of oviducts opens into the body cavity by a funnel shaped opening from each side of the ovary.
(iii) The anterior part of the oviduct is the fallopian tube. It leads into a wider tube called the uterus.
(iv) The uterus join together to form a median tube called vagina.
(v) The common tube is formed by the union of urinary bladder and the vagina and is called the urinogenital canal or vestibule. It runs backwards and opens to the exterior by a slit-like aperture called vulva.
(vi) A pair of Cowper's gland and perineal gland are the accessory glands present in the female reproductive system

Yes. Hirudin is used as an anticoagulant in medical science.

Man is omnivorous in his food habit. He eats plant and animal food. Therefore he has well CI developed incisors and canines. Rabbits are herbivorous in mode of nutrition. They need sharp incisors only. Canines or tearing teeth are hence absent in rabbits.

i) The digestive system includes the alimentary canal and the associated digestive glands.
ii) The alimentary canal consists of mouth, buccal cavity, pharynx, oesophagus, stomach, small intestine, caecum, large intestine and anus.
iii) Mouth leads to the buccal cavity.
iv) Through the pharynx it reaches oesopbagus.
v) Oesophagus opens into the stomach followed by smallintestine.
vi) Caecum ispresent in between the snnall intestine and large intestine.
vii) Caecunm contains bacteria that helps in the digestion of cellulose.
viii) Large intestine has colon and rectum.
ix) It finally opens in to the anus.
x) The digestive glands are salivary glands, gastric glands, liver, pancreas and intestinal glands. The secretion of digestive glands help in digestion of food in the alimentary canal.


 

(i) The heart is pear shaped and lies in the thoracic cavity in between the lungs. It is enclosed by pericardium, a double layered membrane.

(ii) The heart is four chambered with two auricles and two ventricles. The right and left auricles are separated by interauricular septum, similarly right and left ventricles are separated by interventricular septum.
(iii) The right auricle opens into the right ventricle by right auriculoventricular aperture, guarded by a tricuspid valve.
(iv) The left auricle opens into the left ventricle by left auriculoventricular aperture guarded by a bicuspid valve or mitral valve.
(v) The opening of the pulmonary artery and aorta are guarded by three semilunar valves.
(vi) The right auricle receives deoxygenated blood through two precaval (superior vena cava) and one postcaval (inferior vena cava) veins from all parts of the body.
(vii) The left auricle receives oxygenated blood from the pulmonary veins from the lungs.
(viii) From the right ventricle arises pulmonary trunk which carries the deoxygenated blood to the lungs and from the left ventricle arises the systemic arch (aorta) which supplies oxygenated blood to all parts of the body.