Recent questions tagged biology-10

Description : How are involuntary actions and reflex actions different from each other? -Biology-10

Last Answer : All reflex actions are involuntary in nature but all involutary actions are not reflexes as the beating of heart is an involuntary action but is not reflex action. Reflex actions are very quick but all ... lie process as circulation of blood, swallowing of food, movement of food in food pipe, etc.

Description : What is the need for a system of control and coordination in an organism? -Biology-10

Last Answer : Co-ordination in this sense refers to the regulation or control of body activity. Plants need very little in the way of a control system. Since growth and reproduction are about the ... control of a nervous system. Hormones regulate slower activities, such as growth, development and reproduction.

Description : How does chemical coordination occur in plants? -Biology-10

Last Answer : It has been found that the growth of plants is regulated by certain chemical substances which are synthesized by the plants in very small amounts. These are known as plant hormones or phytohormones.

Description : How does phototropism occur in plants? -Biology-10

Last Answer : Phototropism is a growth movement induced by a light stimulus. Growth towards a source of light is called positive phototropism, that away from the source is termed negative phototropism. The tips of shoots ... that the tip was, in some way, communicating with the cells of the region of elongation.

Description : What is the function of receptors in our body? -Biology-10

Last Answer : Receptors are usually located in our sense organs, such as the inner ear, the nose, the tongue, and so on. So gustatory receptors will detect taste while olfactory receptors will detect smell.

Description : You can become moody by simply switching on night bulb daily. How can this happen ? -Biology-10

Last Answer : Night bulb reduces the secretion of melatonin hormone. Melatonin controls our day-night or circadian rhythm, healthy digestive and immune system, sexual cycle and moods. A reduced secretion causes insomnia and mood changes besides affecting health of our digestive and immune system.

Description : Which system is working when you start sweating during exercise ? What is its function ? -Biology-10

Last Answer : Reflex activity of the nervous system. Actually 90% of nervous activity is performed through reflexes. It is automatic, involuntary and spontaneous response to a stimulus without consulting the will of ... glands for releasing their secretion. Part of the sweat evaporates and cools, down the body.

Description : Name the nervous system which controls the functioning of internal organs. How does this system work ? -Biology-10

Last Answer : Autonomous or visceral nervous system. The system does not consult the will of the individual. It works on its own inputs. Autonomous nervous system consists of only motor nerve ... innervated. Its post ganglionic fibres secrete acetylcholine into organs for moderating or reducing their activity.

Description : How do tendrils reach the support when they do not have any sensory structures. -Biology-10

Last Answer : Tendrils do not have any sensory structures but still they are able to find their support just as we grope in the dark for finding the switch-board. Tendrils perform circumnutation from their ... shows little growth while the other side grows rapidly so that the tendril coils over the support.

Description : (a) What are plant hormones ? Give one example each of a plant hormone that -Biology-10

Last Answer : Plant Hormones: Phytohormones are chemical substances other than nutrients produced naturally in plants which regulate growth, development, differentiation and a number of physiological ... , respiratory centre. C-Cerebellum Function: Maintains equilibrium and coordinates muscular activities

Description : Name the parts labelled A and B in the neuron drawn above. Which part acquires the information in the neuron ? NCERT Solutions for Class 10 Science Chapter 7 Control and Coordination HOTS Q7 -Biology-10

Last Answer : A-Dendrite, B-Axon Dandrite. Dandrite to cell body or cyton to axon. Electrical impulse In the region of synapse.

Description : What is dormin ? -Biology-10

Last Answer : Dormin is the other name of plant hormone abscisic acid. The hormne induces dormancy in buds and seeds. So it has been called dormin.

Description : Glucagon is secreted when glucose level of blood falls. It mobilises reserve food like glycogen into glucose. What is pregnancy hormone ? Why is it known so ? -Biology-10

Last Answer : Progesterone is called pregnancy hormone. It helps in maintaining pregnancy by non-formation of new ova, promoting thickening and secretory activity of uterine wall and attachment of embryo to the uterine wall.

Description : How does pancreas control glucose level of blood ? -Biology-10

Last Answer : Pancreas produces two hormones Insulin from P-cells of islet of Langerhans and Glucagon from a- cells of islets of langerhans. Insulin is produced when glucose level of blood rises. Insulin helps the cells to withdraw glucose from blood. It also converts glucose into glycogen in liver and muscles.

Description : What are the hormones involved in providing milk to the suckling infant ? -Biology-10

Last Answer : Prolactin (Maternity Hormone). Production of milk. 2. Oxytocin Ejection of milk

Description : Identify and label the parts shown as A and B in the accompanying figure. -Biology-10

Last Answer : Dorsal view of thyroid an parathyroid. A – Thyroid, B- Parathyroid.

Description : How do auxins promote the growth of a tendril around a support? Describe in brief. (CCE 2012) -Biology-10

Last Answer : Auxin is plant hormone which is synthesized at the tip of the shoot. It helps the cell grow longer. When a tendril comes in contact with a support, auxin stimulates faster growth ... , indole acetaldehyde. Synthetic auxins: Napthalene acetic aicd, indole butyric acid, 2,4-dichorophenoxyacetic acid.

Description : What type of plant movement is seen in the diagram of coiling of tendril? -Biology-10

Last Answer : An example of thigmotropism is the coiling movement of tendrils in the direction of an object that it touches.

Description : What is the difference between the manner in which movement takes place in a sensitive plant and the movement in our legs ? -Biology-10

Last Answer : Movement in a sensitive (mimosa) plant Movement in legs of a human 1. The leaves of a sensitive plant like mimosa are sensitive to touch. 1. Leg is in control of nerve muscles. 2. It is not ... in a sensitive plant are nastic movement. 4. The movement in our leg is due to voluntary nervous system.

Description : Compare and contrast nervous and hormonal mechanisms for control and coordination in animals. -Biology-10

Last Answer : Nervous mechanism Hormonal mechanism It is a fast process. It is a slow process. Arteries and glands are affected. It affects the target organ. It transmits in electrochemical form. It transmits ... It does not control metabolism. It controls metabolism. Growth is not affected. Growth is affected.

Description : How are involuntary actions and reflex actions different from each other ? -Biology-10

Last Answer : Involuntary actions Reflex actions 1. Those actions which occur immediately without any thinking are called involuntary actions. 1. Reflex action is an immediate response to an event which does not require ... etc. 2. Reflex actions are controlled by spinal cord. Example: Sneezing, coughing, etc.

Description : How does chemical coordination occur in plants ? -Biology-10

Last Answer : Chemical coordination in plants takes place with the help of plant hormones. In most of the regions where division takes place (meristematic regions) stimuli cells secrete chemical ... substances identify the information by stimulating the other nearby cells and communicating the information.

Description : What is the need for a system of control and coordination in an organism ? -Biology-10

Last Answer : An organism needs control and coordination system for the following functions : (i) To save the body of the organisms from the harmful changes in the environment. (ii) To control the speed of ... involuntary actions. (iii) To have the capability to think and learn for responding to any stimuli.

Description : Which signals will get disrupted in case of a spinal cord injury ? -Biology-10

Last Answer : All the involuntary actions will get disturbed. (ii) Reflex actions will be disturbed because reflexes are located in the spinal cord. Therefore, the quick responses required to safe guard the body will not take place.

Description : How does phototropism occur in plants ? -Biology-10

Last Answer : The movement in any part of a plant due to light is called phototropism. The shoot of plant shows positive phototropism and roots show negative phototropism. Phototropism in plants occurs due to the hormone ... in length of the cells in shady part. So, the plant appears to bend towards light.

Description : Draw the structure of a neuron and explain its function. [AICBSE 2017] -Biology-10

Last Answer : Nerve cell or neuron is the functional unit of nervous system. A nerve cell has three parts- (i) cell body (ii) dendrite (iii) axon Function : The function of nerve cells is to carry information ... stimulus to send it to spinal cord and brain and carry the message from brain to the target organ.

Description : What is the function of receptors in our body ? Think of situations where receptors do not work properly. What problems are likely to arise ? [AICBSE 2016] -Biology-10

Last Answer : Receptors are specialised cells located in our sense organs like ear, nose, skin, tongue and eyes. The function of receptors is to detect information from the environment. For example, olfactory ... hands might get burn as the damaged receptor cannot perceive the external stimuli of heat and pain.

Description : Why are some patients of diabetes treated by giving injections of insulin ? -Biology-10

Last Answer : Insulin hormone regulates blood sugar levels. If this is not secreted in proper amounts, the sugar level in the blood rises. This causes many harmful effects. To treat harmful effects of increased level of blood sugar, the diabetic patients are treated by giving injections of insulin

Description : How does our body respond when adrenaline is secreted into the blood ? -Biology-10

Last Answer : The heart beat increases when adrenaline is secreted into the blood so that more oxygen is supplied to our muscles. The blood supply to the digestive system and skin decreases because the small arteries ... and rib muscles. All these responses enable us to face the situations of fear and anger.

Description : Why is the use of iodised salt advisable ? -Biology-10

Last Answer : It is advised to use iodised salt because thyroid gland needs iodine to produce thyroxin hormone. Thyroxin hormone controls all the metabolic activities of our body like metabolism of carbohydrates, fats and protein etc. Due to the deficiency of thyroxin a disease called goitre is caused.

Description : How does chemical coordination take place in animals ? -Biology-10

Last Answer : Chemical coordination in animals takes place through the hormones secreted by the endocrine glands. Coordination in animals takes place through hormone system as well as nervous system which is ... these hormones. These cells act according to the information that a particular hormone carries.

Description : Design an experiment to demonstrate hydrotropism. -Biology-10

Last Answer : Take two glass troughs A and B and fill each one of them two-thirds with soil. In trough A plant a tiny seedling. In trough B plant a similar seedling and place a c/ay pot inside the soil. ... shows that the root of a plant grows towards water. In other words, the root of a plant is hydrotropism.

Description : How do auxins promote the growth of a tendril around a support ? -Biology-10

Last Answer : When the tip of a tendril touches a support, then the auxins present in its tip move to that side of tip which is away from the support. Auxins promote growth. So, due to more auxins in it, ... the side which is in contact with the support and makes the tendril twirl (or bend) around the support.

Description : How is the movement of leaves of the sensitive plant different from the movement of a shoot towards light ? -Biology-10

Last Answer : Movement of leaves of sensitive plant Movement of a shoot towards light 1. It is a nastic movement which does not depend on the direction of stimulus applied. 1. It is a tropic movement which depends on the ... two sides of the shoot. 4. It is not a growth movement. 4. It is a growth movement.

Description : What are plant hormones ? -Biology-10

Last Answer : Plant hormones are also called phytohormones. Plant hormones are the chemical substances which help in controlling growth, flowering, height, development of plants and their response to the ... types of phytohormones are – auxins, gibberllins, cytokinins, abscisic acid and ethylene.

Description : What is the role of the brain in reflex action ? -Biology-10

Last Answer : There is no role of brain in reflex action. These involuntary actions are controlled by the spinal cord which take place immediately without thinking of how to respond to the stimuli.