Zoology MCQs for NEET — Practice Questions with Answers

Once neurotransmitters are released into the synaptic cleft due to the fusion of vesicles with the pre-synaptic membrane, they diffuse across the cleft and bind to specific receptors present on the post-synaptic membrane to induce a response.

As per the NCERT text, 'mammals is unique in possessing hair.' While other options are also true for mammals, they are not unique to them among all animals. For example, birds also have a four-chambered heart and are homoiothermous, and many vertebrates respire by lungs.

The NCERT text lists 'Oviparous- Ornithorhynchus (Platypus)' as an example. The other options are listed under viviparous mammals.

The NCERT text states, 'They are viviparous with few exceptions and development is direct. Examples: Oviparous- Ornithorhynchus (Platypus)'. Therefore, Ornithorhynchus is the mentioned exception.

From the section '1.2.5 Class', it is stated: 'For example, order Primata comprising monkey, gorilla and gibbon is placed in class Mammalia along with order Carnivora...'

The table 'Salient distinguishing features of all phyla under animal kingdom' shows that 'Organ-system level' is characteristic of Chordata, under which Mammalia falls. The general description of vertebrates also includes 'organ-system level of organisation'.

The NCERT text states: 'Classes, Amphibia, Reptilia, Aves and Mammalia have two pairs of limbs and are thus grouped under Tetrapoda.' Mammary glands are unique to mammals, egg-laying with calcareous shells is characteristic of birds/some reptiles, and poikilothermous is for fishes, amphibians, and reptiles, not mammals or birds.

The NCERT excerpt on mammals mentions, 'Heart is four-chambered.' Additionally, the Vertebrata section states, 'vertebrates have a ventral muscular heart with two, three or four chambers', and mammals specifically have four.

The context states: 'Sexes are separate and fertilisation is internal. They are viviparous with few exceptions and development is direct.' Also, 'Different types of teeth are present in the jaw.' Scales are characteristic of reptiles and some other groups, but not generally mammals according to the provided text which highlights unique features like hair.

The NCERT text explicitly 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. Thus all vertebrates are chordates but all chordates are not vertebrates.' Protochordates, for example, retain the notochord or have it only in larval stages without replacement by a vertebral column.