Zoology MCQs for NEET — Practice Questions with Answers

The NCERT states, 'we have learnt the lesson of transferring genes into plants and animals from bacteria and viruses which have known this for ages – how to deliver genes to transform eukaryotic cells... For example, Agrobacterium tumifaciens... is able to deliver a piece of DNA known as ‘T-DNA’ to transform normal plant cells...'

The NCERT specifies, 'In another method, suitable for plants, cells are bombarded with high velocity micro-particles of gold or tungsten coated with DNA in a method known as biolistics or gene gun.'

As per the NCERT text, 'Classes Chondrichthyes and Osteichthyes bear fins for locomotion and are grouped under Pisces.' Further, Chondrichthyes are described as having a cartilaginous endoskeleton, while Osteichthyes are fishes with a bony endoskeleton (implied by contrast with Chondrichthyes, though not explicitly stated as 'bony endoskeleton' in this specific excerpt, it is a fundamental characteristic of the class Osteichthyes, or bony fish).

The NCERT states, 'The members of subphylum Vertebrata possess notochord during the embryonic period. The notochord is replaced by a cartilaginous or bony vertebral column in the adult.'

The NCERT defines common chordate features: 'Other common features observed in the chordates are the dorsal, hollow nerve cord and paired pharyngeal gill slits.' While other options can be found in some chordates, they are not universal to all chordates, unlike the dorsal, hollow nerve cord and pharyngeal gill slits.

According to the NCERT, 'Gnathostomata has two super classes, Pisces and Tetrapoda. Classes Chondrichthyes and Osteichthyes bear fins for locomotion and are grouped under Pisces.'

The NCERT explicitly states, 'Thus all vertebrates are chordates but all chordates are not vertebrates.'

The NCERT states, 'Besides the basic chordate characters, vertebrates have a ventral muscular heart with two, three or four chambers, kidneys for excretion and osmoregulation and paired appendages which may be fins or limbs.' Protochordates (Urochordata and Cephalochordata) also possess notochord, gill slits, and post-anal tail at some stage but lack a complex ventral muscular heart and kidneys for osmoregulation as distinguishing features of vertebrates.

The NCERT states 'Vertebrates have a ventral muscular heart with two, three or four chambers' and earlier, common to all Chordates (which includes Vertebrates) is 'a closed circulatory system'.

The NCERT mentions, 'Some of the vertebrates do not possess jaws (Agnatha) whereas most of them possess jaws (Gnathostomata). Agnatha is represented by the class, Cyclostomata.' Therefore, Gnathostomata is distinguished from Cyclostomata by the presence of jaws.