Reflex Action

Consider the following four statements (a-d) and select the option which includes all the correct ones only :- (a) Faecal accumulation in the rectum initiates a neural reflex causing an urge for its removal. (b) Reflex action for vomiting is controlled by medulla. (c) Irregular bowel movements causeconstipation (d) Bowel movement cause "Vomiting is the ejection of stomach contents through Anus.

A cylindrical structure P in our body begins in continuation with medulla and extends downwards. It is enclosed in a bony cage Q and surrounded by membranes R. As many as x pairs of nerve arise from the structure P. The structure P is involved in the reflex actions of our body and conduction of nerve impulse to and from another organs S of our body with which it forms CNS. (a) Name the structure P. (b) Name (i) bony cage Q, and (ii) membranes R. (c) How much is x? (d) Name the organ S. (e) What are the reflexes involving structure P only known as?

Assertion :- Conditioned reflex is not present at birth. Reason:- Initially these action require learning and after perfection these become involuntary action.

Give an example of a relation.Which is ( i Symmetric but neither reflexive nor transitive. (ii) Transitive but neither reflexive nor symmetric.(iii) Reflexive and symmetric but not transitive.(iv) Reflexive and transitive but not symmetric.(v) Symmetric and transitive but not reflexive.

The relation R is such that a Rb o*|a|>=|b Reflexive,not symmetric,transitive Reflexive, symmetric,transitive Reflexive,not symmetric,not transitive none of above

Conditioned reflex can be differentiated from unconditioned reflex as the former

Read the following statements(A-D) 1. Hypothalamus controls body temperature,eating and drinking 2.The midbrain receives and integrates visual,tactile and auditory inputs 3.The medulla contains centres,which control respiration,cardiovascular reflexes and gastric secreations 4. The entire process of involuntary response to a peripherical nerve stimulation is called reflex action. How many of the above statements are true?

Differentiate among conditioned reflexes and unconditioned reflexes.

Read the following statement (A–D) : (A) The cerebral hemisphere are connected together by Grey collagen fibre called corpus callosum (B) Limbic system along with hypotyhalamus regulate sexual behaviour and emotions (C) Corpora quadrigemina is found at the dorsal portion of mid brain (D) Medulla contain the involuntary centre which controls the reflex action of cardiovascular system How many of above statements are incorrect ?