CLASS 10TH DAY 5
INTRODUCTION
ACTIVITY 1
Activity 1 asks us to check if the nose has any effect on the taste of food. For this it asks us to eat sugar once with nose open, and once with nose closed; in another instance, it asks us to repeat the same with some other food.
OBSERVATION: Sugar tastes same whether nose closed or open.Food tastes different when we close the nose while eating.
EXPLANATION: When we bring food to our mouth, sensory organs inside the tongue and nose receives the sensory signal. Our brain interprets the signal and tells us about the food. By this, we can know the type of food, and we can even guess the name. When we eat sugar sweet sensor present in the tongue tell us it is sugar. Since there is no smell in sugar, we do not feel any difference in the taste even if our nose is closed.
But when we taste different food ingredient, there is smell part also. The food contains various volatile components like volatile oil in fennel, clove, volatile ester in fruits. When our nose is closed, our brain receives the signal only from taste buds. As a result, the taste feels different. The impact is such that many people can not guess the food if their eyes and nose are closed while eating.
INFERENCE/CONCLUSION:
This experiment demonstrates that taste and smell both help the brain in interpreting the food. To know more👇 👇
Our mind blowing Brain: The highest coordinating centre in our body is brain which is located inside the skull. Brain is protected by a bony structure in the skull called cranium. The three membranes called meninges surround the brain and protect it. The space between meninges is filled with a cerebro spinal fluid which helps the brain from mechanical shocks. Cranial nerves arise from the brain.
Brain is divided into three parts, forebrain, midbrain and hindbrain. The forebrain consists mainly of cerebrum, midbrain doesn’t have any further division and hindbrain consists of pons, cerebellum and medulla.
The main thinking part of the brain is cerebrum. It is a place for faculties such as learning, reasoning, intelligence, personality, etc. All our thoughts and actions are controlled by the cerebrum. The association area of cerebrum controls thinking and memory and stores information and experiences. The sensory area of cerebrum receives information from sense organs and gives sensation. The motor area of the cerebrum sends instructions to various muscles to perform different function. All the voluntary actions are coordinated by the cerebrum.
The function of hindbrain is to control reflex movements of head, neck and trunk in response to visual and auditory stimuli. It also controls the reflex movements of the eye muscles.
Pons helps in regulating respiration, cerebellum helps in maintaining posture and balance of the body and medulla controls various involuntary actions such as heart beat, breathing, blood pressure, coughing, sneezing, secretion of saliva, etc. Know more👇 👇
ACTIVITY 2
Procedure: Activity 2 asks us to put a plant towards a source of light and see what happens to the growth of its shoot and root.
Observation: Upper part of the plant (shoot) bend towards the light while its root moves away from light.
Explanation: Plants does not have a nervous system or nerve fibres, they show response towards change in the environment chemically.Shoot exposed to light form auxin. Auxin now diffuses to the unexposed part of the shoot.
Auxin has growth promoting characteristic in stems. It induces growth in the unexposed parts. As a result, the plant bends toward the light.
Plant bends toward the light. Auxin has an inhibitory action on the root. As a result, root bends away from the light. We can understand this observation by analyzing the needs of the plant also. A shoot of the plant needs light, so they like to grow in the direction of light.
Root need water and mineral from the soil. So they try to move away from the sun. This phenomenon is called Phototropism. To know more👇 👇
ACTIVITY 3
Procedure: Activity 3 asks us to identify the endocrine glands from the given figure.
Explanation: Click the link to learn this through a video.👇 👇
After watching the video it is suggested to read about following terms from the NCERT—->>Pineal gland, Hypothalamus, Pituitary gland, Thyroid Gland, Parathyroid gland, Thymus: Pancrease, Ovary, Testis.
QUIZ TIME: Lets take a quiz to test your understanding.👇 👇
FUN ACTIVITY
Write a poem about observing the world within or around you.we don’t want to bound your imagination hence the poem can be about anything that you feel like writing.
