11 NCERT BIOLOGY

Chapter 22 – Chemical Coordination and Integration 1. Define the following: (a) Exocrine gland (b) Endocrine gland (c) Hormone Solution: Exocrine gland   – these are the glands that liberate their secretions into ducts conveying either on the surface of the body or to particular organs of the body Endocrine gland – these are ductless glands which liberate their secretions into the bloodstream, conveying it to target organs that are located at a distance Hormone – It is a non-nutrient chemical that serves as a intercellular messenger and is secreted in trace amounts 2. Diagrammatically indicate the location of the various endocrine glands in our body. Solution: The diagram depicting the locations of different endocrine glands in the body are as follows: 3. List the hormones secreted by the following: (a) Hypothalamus (b) Pituitary (c) Thyroid (d) Parathyroid (e) Adrenal (f) Pancreas (g) Testis (h) Ovary (i) Thymus (j) Atrium (k) Kidney

Chapter 21 – Neural Control and Coordination 1. Briefly describe the structure of the following: (a) Brain (b) Eye (c) Ear Solution: The structure is as follows: a) Structure of the brain The brain is the central information processing organ of the body acting as the ‘command and control system’. It is protected in the skull. It is covered by three membranes known as cranial meninges – the outer layer is the dura mater which is a fibrous and a tough membrane, the middle layer is the arachnoid, which is delicate and thin, the innermost layer is the pia mater which is an extension of the brain tissue. This layer is extremely vascular and supplied richly with blood The three main regions of the brain are: Forebrain Hindbrain Midbrain Forebrain  – has three main parts – cerebrum, hypothalamus, thalamus Cerebrum forms the most important and major part of the entire brain. It is longitudinally segregated into halves by a deep cleft, each half is known as the cerebra