NEET Practice Questions (MCQs) with Answers & Solutions

The text clearly categorizes this under '(iii) Biological products: Medicines required to treat certain human diseases can contain biological products... Transgenic animals that produce useful biological products can be created by the introduction of the portion of DNA (or genes) which codes for a particular product such as human protein ($\alpha$-1-antitrypsin) used to treat emphysema.'

The NCERT states, '(i) Normal physiology and development: Transgenic animals can be specifically designed to allow the study of how genes are regulated, and how they affect the normal functions of the body and its development, e.g., study of complex factors involved in growth such as insulin-like growth factor.' This directly addresses the question.

According to the NCERT text, 'A specialised centre present in the medulla region of the brain called respiratory rhythm centre is primarily responsible for this regulation.'

The NCERT states, 'Another centre present in the pons region of the brain called pneumotaxic centre can moderate the functions of the respiratory rhythm centre. Neural signal from this centre can reduce the duration of inspiration and thereby alter the respiratory rate.'

The NCERT chapter mentions, 'A chemosensitive area is situated adjacent to the rhythm centre which is highly sensitive to CO2 and hydrogen ions.'

As per the NCERT text, 'Increase in these substances [CO2 and hydrogen ions] can activate this centre, which in turn can signal the rhythm centre to make necessary adjustments in the respiratory process by which these substances can be eliminated.'

The NCERT states, 'Receptors associated with aortic arch and carotid artery also can recognise changes...'

The NCERT states, 'Human beings have a significant ability to maintain and moderate the respiratory rhythm to suit the demands of the body tissues. This is done by the neural system.'

The neural signal from the pneumotaxic center 'can reduce the duration of inspiration and thereby alter the respiratory rate.' A reduction in inspiratory duration would lead to a more frequent cycle of breathing, thus increasing the respiratory rate.

The introductory part of the chapter mentions, 'This process of exchange of O2 from the atmosphere with CO2 produced by the cells is called breathing, commonly known as respiration.'