The Need For Food

Food is needed by animals for:
a) ______, as an immediate source and longer term energy store.
b) ______ and ______ of damaged cells and tissues

There are three main food types:
a) _____________, which can be divided into starches and sugars
b) ____
c) ________

The chemical elements present in carbohydrates are:
______, ________ and ______

The chemical elements present in fats are:______, ________ and ______

The chemical elements present in proteins are:______, ________, ______ and ________

The basic building blocks of carbohydrates are simple sugars, like ________. Carbohydrates may also be complex molecules like ______.

Proteins are large molecules made up of long chains of _____ _____ joined together.

A fat molecule consists of three _____ _____ joined to a ________ molecules in the shape of a letter E.

Digestion is the breakdown of _____ particles of food into ______ particles so that they can be ________ into the blood through the wall of the small intestine.

During digestion large ________ food particles into smaller ________ food particles.

Teeth are involved in the _________ __________ of food.

Incisors are ______ shaped for _______ and _______

Canine are _____ pointed for _______, _______ and holding ____

molars and premolars are large teeth with ______ surfaces for _______ and _______ food.

An animals _________ is the number and type of teeth that it possesses. This depends on what type of food the animal eats.

A herbivore is an animal that eats _____.

A carnivore is an animal that eats _______

An omnivore is an animals that eats _____.

The digestive system consists of the gut running from the _____ to the ____.

Saliva

gastric juices

pancreatic juice

bile

intestinal juice

_________ is the name given to the muscular contractions of the gut wall.

During peristalsis circular muscles in the gut wall _______ behind the food while the muscles in front of the the food _____. This pushes the food along the gut.

The muscular contractions of the stomach wall help to mix the food with the gastric juice. This _____ __ the chemical breakdown of the food.

Digestive enzymes are chemicals which breakdown the large molecules of carbohydrates, proteins and fats down into

______ enzymes act on carbohydrates, ________ enzymes act on proteins while ______ enzymes act of fats.

_______ enzymes are responsible for the breakdown of carbohydrates, proteins and fats

The ________ is the substance an enzyme acts on

The ________ are the substrates produced at the end of the reaction.

Enzyme- Amylase
Substrate- Starch
Product-

Enzyme- Protease
Substrate- Protein
Product-

Enzyme- Lipase
Substrate- Fats
Product-

Main functions of the small intestine:
- to _________ digestion
- to ______ the digested foods across the wall of the small intestine into the bloodstream

The small intestine has a ____ _____ _______ ____

The surface area is very very large because the small intestine is very ____. The internal lining is ______ and has thousands of tiny _____ present.

The small intestine's internal lining is very ___ which allows digested foods to pass through into the blood _____ and _______

The small intestine has a very ____ _____ ______ which absorbs food _______ and carries it away quickly to the rest of the body.

The _____ are well adapted for the absorption and transport of food.

Villi have a ____ _____, which allows digested food to pass through _______

Villi have a large network of _____ ________ into which ______ and _____ _____ are absorbed and then carried away quickly

Villi have a _______ into which digested fats are absorbed.

In a lacteal, fats are then quickly transported away in the _________ ______ and are eventually emptied into the bloodstream.

Any undigested food material passes from the end of the ________ into the _______

The undigested material passes along the large intestine then _____ is absorbed from it.

The faeces is stored in the ______ until it is passed out of the body through the ____