Assertion (A): The SA node (sino-atrial node) is the natural pacemaker.

Reason (R ): Generates the action potentials in the conducting system.

The tricuspid valve is present between

Mechanism of regulation, between the organism and its environment of solutes and the loss and gain of water is known as

Most of the marine invertebrates are _______.

Assertion (A):During heavy exercise the anabolic process of carbohydrate occurs in our body

Reason (R ): Heavy exercise  needs more energy so glucose is converted into pyruvic acid.

In a 28 days menstrual cycle, the ovulation occurs on the ________ th day.

Seasonal breeders exhibit oestrous cycle throughout their life

Metabolic end products and other waste products from the fetal body are excreted into

the mother’s blood through placenta

Which male hormone is responsible for secondary sexual characters?

Which hormone is responsible for parturition?

A process by which urine is voided from the urinary bladder is __________.

The normal urinary output is 3L/day

A tuft of capillaries enclosed by Bowman capsule is called ___________.

The primary function of kidney is homeostasis

The total number of alveoli present in the human lungs is estimated to be around ______.

A.Oxidative Phosphorylation- 1) Breathing between the atmosphere and the alveoli

 B.Internal respiration             - 2) Exchange of gases between the bloodstream and tissue cells

C.External respiration    - 3) Production of ATP

D.Expiration                           - 4) Exchange of gases between alveoli and the bloodstream

 5) Taking in of oxygen