(a) Define excretion. Name any two substances that are selectively reabsorbed.
(b) Draw and label the following parts in the human excretory system.
(i) Right kidney (ii) Urinary bladder (iii) Right renal artery

Draw a diagram of human excretory system and label the following : (i) Urinary bladder (ii) Left kidney (iii) Left ureter

Given below is a diagram of the human heart. Draw it in your notebook and label the following parts. right ventricle

Given below is a diagram of the human heart. Draw it in your notebook and label the following parts. right auricle

Draw the structure of the human ear and label the following parts: (i) tympanum, (ii) cochlea, (iii) pinna, (iv) malleus, (v) semi-circular canals, (vi) eustachian tube.

Mention the function of any two of the following used in communication system : (i) Transducer (ii) Repeater (iii) Transmitter (iv) Bandpass Filter

(a) Draw a diagrammatic sectional view of the female reproductive system of human and label the parts (i) where the secondary oocytes develop (ii) which helps in collection of ovum after ovulation (iii) where fertilization occurs (iv) where implantation of embryo occurs. (b) Explain the role of pituitary and the ovarian hormones in menstrual cycle in human females.

(a) Draw a diagrammatic sectional view of the female reproductive system of human and label the parts (i) where the secondary oocytes develop (ii) which helps in collection of ovum after ovulation (iii) where fertilization occurs (iv) where implantation of embryo occurs. (b) Explain the role of pituitary and the ovarian hormones in menstrual cycle in human females.

(a) Draw a labelled diagram of excretory system in human beings and label the following: (i) left kidney, (ii) renal artery, (iii) urinary bladder, (iv) urethra (b) Name the functional unit of kidney. (c) Name two nitrogenous wastes released from kidney.

The diagram given below is that of a structure present in a human kidney. Study the same and answer the questions that follows : (i) Name the structure represented in the diagram. (ii) What is the liquid entering part T called? Name two substances present in this liquid that are reabsorbed in the tubule. (iii) What is the fluid that comes to part '2' called? Name the main nitrogenous waste in it. (iv) Mention the three main steps involved in the formation of the fluid mentioned in (iii) above. (v) Name the substance which may be present in the fluid part '11 if a person suffer from diabetes mellitus.

(a) Name the hormone that initiates spermatogenesis in humans. Describe the process of spermatogenesis in spermatogenesis in sequence mentioning the ploidy of the cells at each step. (b) Draw the diagram of a mature human sperm and label the parts that : (i) helps it reaching to the ovum . (ii) providing energy for it to reach the ovum. (iii) helping it to gain entry into the ovum.