STD 11 - 16. Excretory product and their elimination — NEET STD 11 Science — Question

Read the following statements.
(A) Fertilisation is external with direct development in echinoderms.
(B) Echinus is commonly known as sea urchin; Antedon as sea lily; and Cucumaria as sea cucumber.
(C) Asterias is commonly called star fish and ophiura as brittle star.
(D) The body of hemichordate is cylindrical and composed of anterior proboscis, a collar and a long trunk.
(E) In hemichordate respiration takes place through gills and excretory organ is proboscis gland.
(F) Fertilisation is external with direct development in hemichordates.
(G) Chordates are fundamentally characterized by the presence of a notochord, a dorsal hollow nerve cord and paired pharyngeal gill slits.
(H) Subphyla urochordata and cephalochordata are often referred to as protochordates and is exclusive marine.
(T) In urochordata, notochord is present only in adult tail.
(J) The notochord is replaced by a cartilaginous or bony vertebral column in the adult of vertebrata
(K) Cyclostomates are ectoparasites on some fishes. They have an elongated body bearing 6 - 15 pairs of gill slits for respiration.
(L) Chondrichthyes have sucking and circular mouth without Jaws. Their body is devoid of scales and paired fins.
(M) Cranium and vertebral column are cartilaginous in cyclostomes. After spawning, within few days they die.
(N) The mouth of cyclostomates is located ventrally and teeth are modified placoid scales which are backwardly directed.
(0) Due to the absence of air bladder chondrichthyes have to swim constantly to avoid sinking.
(P) Gill cover is known as operculum, which are absent in chondrichthyes.
(Q) In some species of chondrichthyes like torpedo have poison string and trygon have electric organ.
Choose the correct option given below :-

Fill in the blanks and choose the correct option given below.
(i) CO₂ + H₂O ⇔ H₂CO₃ The above reaction is catalyzed by enzyme A , which is present in higher concentration in B and in minute concentration in C of blood.
(ii) Every 100ml of deoxygenated blood delivers approximately D ml of CO₂ in alveoli.
(iii) Exchange of O₂ and CO₂ at the alveoli and tissues occur by E .
(iv) Respiratory rhythm is maintained by the respiratory centre in F region of brain.
(v) A G centre in pons region of brain and chemosensitive area in the medulla can alter respiratory mechanism.
(vi) The chemosensitive area in medulla is sensitive to H and I.
(vii) Receptors associated with aortic arch and J recognize changes in CO₂ and H concentration.
(viii) K is a difficulty in breathing causing wheezing due to inflammation of bronchi and bronchioles.
(ix) Emphysema is a chronic disorder in which L are damaged due to which respiratory surface is decreased.
(x) Long exposure to dust, in industries involving grinding or stone-breaking, can lead to inflammation leading to M and thus cause serious lung damage.

Lippe's loop is a typer of contraceptive used as:

Mineral present in red pigment of vertebrate blood is

What do you mean by the term spermateleosis

In Mendelism, linkage was not observed due to

Which of the following cells during gametogenesis is normally diploid ?

Identify the wrong statements for poriferans from given statements.
(i) Metameric segmentation present in poriferans
(ii) Notochord is a mesodermally derived in poriferans.
(iii) Poriferans are primitive multicellular and have cellular level of organisation.
(iv) Digestion is intracellular in poriferans
(v) Poriferans are hermaphrodite and fertilisation is internal.

Calcium is important in skeletal muscle contraction because it

The biggest phylum in regard to the number of species is