2. c. Dense regular.
4. Yes. All vertebrates have notochord which is replaced by vertebral column. But there are chordates other than vertebrates (Urochordates and Cephalochordates).
5. (a) Tidal volume: Volume of air inspired or expired during a normal respiration.
Residual volume: Volume of air remaining in lungs after a forcible expiration.
(b) Vital capacity: Volume of air that can breathe in after a forced expiration.
Total lung capacity: Total volume of air in the lungs after a maximum inspiration.
6. (a) Hippocampus (Seahorse).
(c) Bony fishes, scales are cycloid, ctenoid etc., gills covered by operculum.
7. a) i. Salivary amylase (Ptyalin). ii. Lysozyme.
b) i. Small Intestine. ii. Stomach.
8. a) AB blood group has no antibodies. So AB group persons can receive blood from other groups.
b) Hypertension, Coronary artery disease.
9. (a) Gnathostomata
10. a) i. Glycosuria. ii. Ketonuria
b) Diabetes mellitus
11. (a) A= Actin, B= Myosin
(b) A= G- actin, B= Meromyosin (HMM + LMM)
12. (a) Glucagon
13. (a) A= Secondary structure of protein, B= Tertiary structure of protein.
(b) Primary structure and quaternary structure.
15. (a) Dog fish. It is true fish. Others are not true fishes and are invertebrates.
(b) Saw fish. It comes under class chondrichthyes. Others belong to osteichthyes.
(c) Sea hare. It belongs to Mollusca. Others are echinoderms.
17. (a) Electrocardiograph
(b) P wave: Depolarization of atria.
T wave: Ventricular repolarization.(c) It is used to diagnose heart diseases.
18. (a) Walls of blood vessels and lung alveoli.
(b) Cuboidal (cubical) epithelium.
(c) Secretion and absorption.
(d) Lining of stomach and intestine.
(e) Ciliated epithelium.
(f) Movement of particles.