The respiratory system of cockroach is very well developed and consists of a network of branched closed tubes, called flame cells.

A well developed archegonium with neck consisting of 4 - 6 rows and neck canal cells , characterises

Assertion . In cymose tap root systemm the oldest branch lies very close to growing point of root while the youngest branch is farthest away from it Reason . In cymose tap root system, the primary roots itself stops growing after some time, but secondary roots carry on further growth of the system

Fill up the blanks in the following paragraph by selecting the correct option The vascular system of frog is well-developed ul("I") type. The blood vascular system involves heart, blood vessels and blood. Heart has 3 chambers, two atria and one ventricle and is covered by a membrane called ul("ii") . A triangular structure called ul("iii") joins the right atrium.

Which of these statements are fasle regarding the human respiratory regarding the human respiratory system ? (a) The nasal chamber opens into the pharynx . (b) Trachea, bronchus and initial bronchioles are supproted by complete cartilaginous rings. (c ) The branching network of bronchi, bronchioles and alveoli comprises the lungs. (d) Pleural fluid increase friction on the lung surface.

Select the option with a correct representation of phylum of animal to the below - mentioned features : I. The body is supported by a skeleton made up of spicules or spongin fibers with choanocytes line the spongocoel. II. Specialized cells called flame cells help in osmoregulation and excretion. III. The body bears eight rows of ciliated comb plates which helps in locomotion. IV. The alimentary canal is complete with the well developed muscular pharynx.

$ Mitochondria are called "Food-Factories" of a plant cell. A Plant cell is called as a closed system.

Identify correct pair of statements (i) Attraction between two molecules of water present in oxylen channel is adhesion (ii) Number of O_(2) molecules absorbed is more than number of CO_(2) molecules released when triolein is respiratory substrate (iii) Bacillus mycodies is nitrifying bacteria (iv) Continuous system of cell walls and intercullular spaces in plant tissues is called apoplast 1 ii and iii 2 iii and iv 3 ii and iv 4 I and iv.