Nutriton In Animals

i. A patient is given glucose when he/she is

a. unable to eat food.

b. unable to digest food.

c. in an emergency for energy.

ii. Till the crisis is over.

iii. Glucose drip has the following benefits:

a. It needs not be eaten.

b. It needs not be digested.

c. It gives instant energy.

a. Ingestion, digestion, absorption, assimilation and egestion.

The breakdown of complex food substances into simpler substances is called digestion.

b. Liver.

Liver secretes bile juice that is stored in a sac called gall bladder.

c. Gastric

(Gastric juices or digestive juices breakdown the proteins into simpler substances.)

d. Villi.

The villi increase the surface area for absorption of the digested food.

e. Food vacuole

Digestive juices are secreted into the food vacuole. They act on the food and break it down into simpler substances

(a). False.

Digestion of starch starts from the mouth.

(b). True.

Tongue mixes saliva with the food during chewing and helps in swallowing food.

(c). True.

Bile juices is stored in a sac called gall bladder.

(d). True.

The ruminants bring back partially digested food called cud into their mouth and chew it for some time. Ruminants include cattle, sheep, goats, buffalo, deer, etc.

Vitamins are bio-chemicals that help the body in performing various activities.

i. Vitamins are necessary for the following purposes:

a. Vitamins help to protect the body against diseases.

b. Vitamins help in proper functioning of body and mind.

ii. All green leafy vegetables and fruits provide vitamins.

Papaya is the richest source of vitamins.

Deciduous teeth or primary teeth, are called babyteeth, temporary teeth and milk teeth - any set of milk teeth in children or young mammals fall and the permanent teeth take their place (in children all the milk teeth fall out and are replaced by new ones by the ages of about six and twelve).

The complete digestion of food takes place in the small intestine.


The carbohydrates get broken into simple sugars such as glucose, fats into fatty acids and glycerol, and proteins into amino acids.

The large intestine is wider and shorter than small intestine. It is about 1.5 metre in length. Its function is to absorb water and some salts from the undigested food material.

Carbohydrates : Sugar

The digestion of carbohydrates begins in the mouth and complete when it is broken down into simple sugar which can be absorbed by the body.

Proteins : Amino acids

Proteins are digested into stomach and small intestine. They are broken down into amino acids by enzymes.

Fats : Fatty acids and glycerol

Fat from food is broken down into fatty acids and glycerol. The bile plays an important role in the digestion of fats.

The inner surface of the small intestine has numerous finger-like projections called villi (Singular villus), as shown in the figure:

Villi increase the surface area which helps in absorption of the digested food especially fatty acids and glycerol. Also, the blood vessels in that help in absorbing the nutrients into the blood.

Liver is the largest gland in the body. It produces and secretes bile juices that is stored temporarily in a sac called gall bladder.
Bile plays an important role in the digestion of fats.

It is dark yellow to dark brown in colour.

Cellulose is a type of carbohydrate that can be digested by ruminants but not by humans. The grass is rich in cellulose. Human beings cannot digest cellulose in their food like cattle due to the absence o rumen.

The digestive system of ruminant is shown below:

Glucose provides instant energy because glucose is a simple sugar molecule. This means that glucose doesn't need to be broken down further by the body. Whenever taken directly, it gets directly absorbed in the bloodstream and provides the body with energy. Unlike, carbohydrates (which are complex molecules), glucose gets digested faster and the energy quickly released.

i. small intestine.

In the small intestine, finger like projections called villi increases the surface area for the absorption of food.

ii. Buckle cavity (teeth)

Our teeth very in appearance and perform different functions.

iii. Stomach

The inner lining of the stomach secretes hydrochloric acid which kills the bacteria and makes the medium in the stomach acidic.

iv. Small intestine

The complete digestion of food takes place in the small intestine.

v. large intestine.

The fecal matter is removed through the anus from time-to-time.

Similarity: Both amoeba and human beings are heterotrophs as they drive their food from other plants or animals.

Difference: In humans, digestive juices are secreted in the buccal cavity, stomach and small intestine. Whereas in Amoeba, digestive juices are secreted only in the food vacuole.

(a)- (iii), (b)-(iv), (c)-(i), (d)-(ii), (vii), (e)-(v), (f)-(vi)

(a) Salivary : (iii) Saliva secretion

In the mouth, salivary glands secrete the saliva which breaks down the starch into sugars.

(b) Stomach : (iv) Acid release

The inner liningof the stomach secretes acid which kills the bacteria that enter along with the food and makes the medium in the stomach acidic.

(c) Liver : (i) Bile juice secretion

Liver is the largest gland of the body which secretes the bile juice. Bile plays an important role in the digestion of fats.

(d) Rectum : (ii) Storage of Undigested food

Rectum is a part of large intestine. The remaining waste passes into the rectum and remains there as semi-solid faeces.

(e) Small intestine : (v) Digestion is completed

The complete digestion of food takes place in the small intestine. Here, carbohydrates break into simple sugar, proteins into the amino acids and fats into fatty acid and glycerol.

(f) Large intestine : (vi) Absorption of water

Large intestine is the 1.5 meter in length. Its function is to absorb water and some salts from the undigested food material.

The following diagram is the labelled diagram of the human digestive system:

Fig. Human digestive system

No, we cannot survive only on raw, leafy vegetables/ grass because we cannot get all the nutrients like proteins, fats, vitamins, carbohydrates from them. Moreover, grass is rich in cellulose which is a type of carbohydrate that humans are not able to digest due to the absence of rumen.

We must have to ingest nutrients rich food for growth, maintenance and multiplication. So, only green leafy vegetables will not solve the purpose.