KIDNEY

The juxtraglomerular cells of kidney secrete two hormone as renin and erythropoieten.
FUNCTION OF RENIN
-It operates RAAS system and brings about vasoconstriction resulting increased blood pressure and also increased salt and water retention.

FUNCTION OF ERYTHROPOIETIN

-It activates bone marrow cells to produce more RBC called erythropoiesis.

OVARY

Location-Primary sex organ of female lies in abdomen.
STRUCTURE & FUNCTION
-Ovary produces one ovum during each menstrual cycle and two group of steriod hormone as estrogen and progesteron.
-It is composed of ovarian follicle and stromal tissue.
-Estrogen are mainly secreted by developing graffian follicle while progesterone are secreted by corpus luteum after ovulation.
FUNCTION OF ESTROGEN 
-Stimulates growth of female secondary sex organ.
-Growth of ovarian follicle.
-Appearance of secondary sexual character as high pitched voice,development of mammary gland,onset of mammary gland etc.
-It also regulate female sexual behaviour.
FUNCTION OF PROGESTERONE
-It prepares endometrium for implantation,development of placenta,maintenance of pregnancy and formation of alveoli for storing milk and its secretion.

TESTIS

Location-One pair in scrotal sac outside the abdomen of male.
Structure and its hormone-
-It is primary sex organ as well as endocrine gland.
-It is made up of seminiferous tubules and leydig cells.
-The leydig cells secrete a group of hormone collectively called androgens.
-Testosterone is main androgen.
FUNCTION-
-It regulates the development,maturation and function of accessory sex organs like epididymis,vas deference,seminal vesicle,prostrate gland,urethra etc.
- It also brings about secondary sexual character of male as beard,moustaches,low pitched sound,musgular growth,axillary hairss,aggressiveness etc.
-It also acts on CNS and increased libido(sexual behaviour).
-Steriod hormone testosterone and other androgens are anabolic(synthetic)hormone which are engaged in protein and carbohydrate metabolism. 

STRUCTURE OF BRAIN

Brain is divided in to three parts-

(A)Fore brain       (B) Mid brain    (C)Hind brain

(A)Fore brain or Prosencephalon:-

It is the frontal or anterior part of brain constists three parts-

(a)Cerebrum   (b)Thalamus   (c)Hypothalamus 

(a)Cerebrum:-

-It is the largest part of the brain.
-It is divided in to two halves called cerebral hemisphere.
-Both cerebral hemisphere is connected by corpus callosum.
-Corpus callosum is a long,thickand curved band of myelinated nerve fibre.
-Left hemisphere control right side and right hemisphere control left side.
-Surface of cerebrum is highly folded.
-The upper layer of cerebrum is known as cerebrum cortex made up of grey matter which control muscle movement and also involve in hearing,vision,memory,sensation and communications.
-Inner part of cerebrum is known as cerebrum medulla which is made up of mylinated nerve fibre and appears white.

(b)Thalamus:-

-It is the lateral part of diencephalon formed of mostly gray matter.
-Cerebrum extend around thalamus.
-Major function of thalamus to cordinate moter and sensory signals so also called relay station.

(c)Hypothalamus:-

-It is the floor of diencephalon where gray matter are scattered in white matter.
-It is very importent part of brain.
-It controls body temperature,appetite centre(urge for eating),osmoregulation,sweating,sleep,respiration,heart beat etc.
-Neurosecretory cells of hypothalamus secrete hypothalamic hormone also callrd super ,aster gland.

(B)Mid brain:-

-It is also called mesencephalon.
-It is small part of brain present between hypothalamus of the fore brain and pons of the hind brain.
-In this part nervr cells are scattered in white matter.
-A narrow canal passes through mid brain called cerebral aqueduct.
-Main function of mid brain is control to auditary reflex and visual reflex(movement of eye ball and head to focus on an object).
-Mid brain and hind brain form brain stem. 

(C)Hind brain:-

-It is also called rhomboencephalon.
-It is composed of three component.

1. Cerebellum    2.Medulla oblongata       3.Pons varolli

1.Cerebellum:-

-It lies behind the cerebrum.
-It is highly developed in bipedal mammals.
-It surface is highly convoluted to provide extra space for neurons.
-It controls body balance,rapid muscular activity such as cycling,running,typing etc.

2.Medulla oblongata:-

-It is the posterior part of hind brain which gradually tapers to form spinal cord.
-It controls respiration,cardiovascular reflex,gastric secretion and has reflex centre fore vomiting,sneezing,salivation etc.

3.Pons varolli:-

-Its nerve fibre connects cerebrum,cerebellum,medulla and spinal cord.


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SPINAL CORD

-It is a part of CNS.
-It is cylindrical,42-45cm.long and 2cm. thick in mid thoracic region.
-It is more thicker in lower cervical and mid lumber region and smallest at the inferior tip.
-It stop growing at the age of 4 or 5 years.
-Spinal cord acts as a link between the brain and the nerves that stretch throughout the body.
-In spinal cord gray matter are present in inner while white matter is outer side.
-31 pair spinal nerve origanetes from spinal cord.