CBSE Questions for Class 7 Biology Nutrition In Animals Quiz 3 - MCQExams.com

• The digestive system includes the alimentary canal and associated glands to carry out the digestion of food and release the energy stored in these food substances.
• The nutrients from digested food are then absorbed in the small intestine of the alimentary canal and carried to different organs via the circulatory system.
• The primary function of the respiratory system is to allow atmospheric oxygen from the air to enter the blood and carbon dioxide from the blood to exit into the air. 
• The endocrine system includes endocrine glands and maintains the homeostasis of the body through hormonal actions. 
• The nervous system serves in the reception of sensory input followed by their integration in the brain and spinal cord and generation of motor output to produce the response. 

• Amylase is an enzyme that breaks down complex starch molecules into simple sugars. 
• It is found in the saliva, present in the mouth. 
• it is also released by the pancreas. Due to the presence of amylase in the saliva, it is said that the digestion process starts from the mouth itself.
• Bile juice acts on fats. HCl is not an enzyme, it is an acid. 
• Pepsin is an enzyme that helps in the digestion of proteins.

• The canines are the pointed and the sharp teeth which are found in the mouth of the humans. 
• These are the teeth that are used for tearing of the food. The sugarcane is made up of tough fibers. These fibers can be torn with the help of canine teeth. 
• Thus, the correct answer is option B. 

• The pancreas helps in digestion by secreting pancreatic juice in the small intestine. 
• However, the pancreas is a gland and is not a part of the alimentary canal.
• The alimentary canal is a muscular tube that extends from mouth to anus and includes the mouth, pharynx, esophagus, stomach, and intestines.

$$\textbf{Correct answer: D}$$  

$$\textbf{Option (A):}$$  

$$\bullet$$  Digestion of protein takes place in the stomach in the presence of the enzyme pepsin. 

$$\textbf{Option (B):}$$  

$$\bullet$$ The food pipe or oesophagus helps with the movement of food from the buccal cavity to the stomach.

$$\textbf{Option (C):}$$  

$$\bullet$$  Small intestine is the region of the highest absorption of nutrients where complete digestion of the nutrients takes place in the presence of pancreatic juice and intestinal juice.

$$\textbf{Option (D):}$$  

$$\bullet$$ Water from the undigested food material is absorbed in the large intestine. 

$$\bullet$$ Along with water, the minerals are also observed through the epithelium of the large intestine. 

$$\bullet$$ This absorption of water produces the faeces without its water which gets excreted through the anus.

Hence, the correct answer is option (D).

$$\textbf{Correct answer: C}$$  

$$\bullet$$ The presence of a ruminant stomach makes an animal ruminant.

$$\bullet$$ These animals have the ability to digest plant-based food and act on the degradation of cellulose due to the presence of specific enzymes in them. 

$$\bullet$$ There are microorganisms present in the ruminant stomach which cause the fermentation of food and facilitate the digestion of cellulose. 

$$\textbf{Option (A):}$$  

$$\textbf{Option (B):}$$  

$$\textbf{Option (C):}$$  

$$\bullet$$ A dog is not a ruminant animal because they do not have a plant-based diet and the dietary function is completely different. 

$$\textbf{Option (D):}$$  

$$\bullet$$ Goats are also ruminant animals as they are herbivores and contain the ruminant stomach.

Hence, the correct answer is option (C).

• Rumination is also called second chewing. 
  
• Ruminant stomach: The stomach of a ruminant is divided into four chambers – the rumen, reticulum, omasum, and abomasum. 
• The process of digestion is as follows: The food is chewed and swallowed quickly and passed into the first stomach called Rumen. The microorganisms help in breaking down the food. Digestive juices of the rumen partially digest the food. The partially digested food in the rumen is called cud.