Control and Coordination Test -16

Thyroxin is secreted by the thyroid gland to regulate the metabolic rate and help control body temperature; Insulin and glucagon are hormones that help regulate the levels of blood glucose in the body secreted by pancreas; The testes  are the most essential organs of the male reproductive system. They are the glands where sperm and testosterone are produced; Estrogen is a  female steroid hormone that is produced by the ovaries.

The Temporal Lobe mainly revolves around hearing and selective listening; The parietal lobes can be divided into two functional regions. One involves sensation and perception and the other is concerned with integrating sensory input, primarily with the visual system; The occiptial lobe is important to being able to correctly understand what your eyes are seeing; frontal lobe is used on everyday basis. You use it to make decisions, such as what to eat or drink for breakfast etc

The central nervous system (CNS) is made up of the brain, the spinal cord, and the optic nerves; the nervous system outside the brain and spinal cord; the part of the nervous system responsible for control of the bodily functions not consciously directed, such as breathing, the heartbeat, and digestive processes; Reflax action is an involuntary and nearly instantaneous movement in response to a stimulus.It is made possible by neural pathways called reflax arc.

It is a  condition of severely stunted physical and mental growth owing to untreated congenital deficiency of thyroid hormone; Gigantism is a rare condition that causes abnormal growth in children cause by growth hormones; protrusion of the eyeball from the orbit, caused by disease, especially hyperthyroidism, or injury; A disorder of salt and water metabolism marked by intense thirst and heavy urination.

Thyroxin is one of the major hormone secreted by thyroid gland as well as Calcitoninis a hormone secreted by the thyroid gland that reduces the concentration of blood calcium level when it has risen to an above normal level. 

Pancreas is known as a mixed gland because it performs functions of both exocrine and endocrine glands; and Most hormones produce an effect on specific target tissues that are sited at some distance from the gland secreting the hormone.

When blood vessels dilat, the flow of blood is increased due to a decrease in vascular resistance, the urinary bladder is a hollow elastic organ that functions as the body's urine storage tank, The pupil is a hole located in the center of the iris of the eye.

Plant growth regulators function as chemical messengers for intercellular communication . There are currently five recognized groups of plant hormones: auxins, gibberellins, cytokinins, abscisic acid (ABA) and ethylene. They work together coordinating the growth and development of cells.

The main function of auxin is to help plants grow. Auxin stimulates plant cells to elongate, and the apical meristem of a plant is one of the main places that auxin is produced.

Hormones known as posterior pituitary hormones are synthesized by the hypothalamus, and include oxytocin and antidiuretic hormone.

The area of the plant which perceives a stimulus is called as perceptive region. Tip of the stem is the perceptive region for the light. The area of the plant which shows the response is called as responsive region. 

Auxin is the hormone that stimulates cell elongation and growth. In the shoot when light falls on it the hormone gets activated and also promote the movement of shoot towards the light.

Geotropism is the response of the part of the plant to the gravity stimulus. Frank introduced the term geotropism for the active force which is liberated by gravity within various parts of the plant. He also distinguished three types of geotropism- positive, negative and transversal geotropism. The response of the plant towards the gravity is known as positive geotropism while the response of the plant away from gravity is known as negative geotropism. Transversal geotropism is a direction of growth that is vertical to the shoot axis such as many lateral shoots and side roots. 

Hydrotropism is the response of the plant towards the water stimulus. It was first demonstrated by Johnson in 1829. During the course of his experiments, he found that when the air into the roots of seedlings penetrated, the roots continued to grow downwards. Hydrotropism can be positive as in case of growth of roots towards the water and also negative which is shown by shoot growing away from the water source. 

The cerebral aqueduct, also known as the aqueductus mesencephali, mesencephalic duct, sylvian aqueduct, or aqueduct of Sylvius, is within the mesencephalon (or midbrain), contains cerebrospinal fluid (CSF), and connects the third ventricle in the diencephalon to the fourth ventricle within the region of the mesencephalon and metencephalon, located dorsal to the pons and ventral to the cerebellum. 

The positive response of the plants towards the gravitation is called geotropism. Geotropism means response to gravity if the response is in the direction of the gravity then it is called positive geotropism since root is growing downwards (in the direction of gravity) so it is called positive geotropism.

Meninges are the three connective tissue membranes that enclose the brain and spinal cord. Piameter is the innermost membrane which is thin, delicate and vascular. The next membrane is arachnoid which is thin and webby. Durameter is the outermost membrane which is tough, dense and fibrous in nature.