3. Give a detailed explanation of digestion in oral cavity, stomach and intestine.
4.Express photosynthesis process in detail.
5.what are the guard cell? give their functions and their diagram.
Answers
Answer:
3. In the oral cavity saliva is present also known as salivary amylase which partially digests the maltose,a carbohydrate component present in our food.The oral cavity also has teeth of 4 types that help in breaking,tearing , grinding and chewing the food.
Our stomach contains an acid known as hcl that helps in digestion of food and convert the food into chime for further digestion.
Intestine is the main part of digestion as here the nutrients from the digested food is absorbed.
4. 'Photo' means "light" and 'synthesis' means "to prepare". The sunlight is absorbed by the chlorophyll cells present in leaves of plants and is converted into soluble form for preparation of food via various means of chemical processes.
5. Guard cells are present in the outermost part of stomata and are also referred to as the stomatal pores.They are responsible for the opening and closing of the stomatal pore for exchange of various substances.
Explanation:
3.The role of saliva is to-
- make the food moist so as to help in ease of swallowing
- help in partial digestion of carbohydrates
- keep our teeth free from bacteria and maintain the pH level of our oral cavity.
HCl helps to digest the food and kill the harmful bacteria that enters our body along with the food .A basic chemical called peptone is released by the pancreas which becomes active in the acidic medium to form peptin that help in protein digestion.
The surface of the small intestine have hair like structures called villi that helpes in -
- increasing the surface area of the intestine
- absorption of nutrients from the food.
The food is taken in through the Buccal cavity and is then passed through the oesophagus to the stomach to the small intestine to the large intestine where left out excess water is reabsorbed ensuring complete absorption of nutrients and least wastage of food and the remainings are stored in the rectum and waste is given out through the anal.
4. The process of photosynthesis takes place in two phases-
- light dependent phase or light reaction-usually takes place at daytime in presence of sunlight.
- light independent phase or dark reaction-usually takes place at night in the absence of light.
The process of photosynthesis requires two energy currencies namely- ATP & NADPH.
5. The guard cells are the only epidermal cells having their own chloroplasts. They open up when there is excess water pressure and they become turgid to allow water and gases to pass in and out and become flaccid to close up the opening due to decrease of water pressure.this water pressures are controlled by the hormones present in plants.You can get the figure in the link:
https://images.app.goo.gl/oyawZRtqwXkLokRaA