MAMMAL AS A CONSUMER Flashcards
What is ‘Mechanical Digestion’?
Mechanical digestion is the physical breakdown of food by the action of teeth and muscle movement.
Purpose - to increase the surface area of the food so that chemical digestion occurs faster. This includes mastication and muscle churning of the stomach.
What is ‘Chemical Digestion’?
Chemical digestion is the breakdown of food by the action of acids and enzymes.
Purpose - the use of enzymes and digestive juices break down food into microscopic sized particles, called nutrients. This includes saliva in the mouth, stomach acid, and duodenum in the small intestine.
What are the ‘7 Life Processes’?
Mammals need to consume food in order to provide the energy required to carry out the seven life processes common to all living organisms.
Movement - All living things move in some way. This may be obvious, such as animals that are able to walk, or less obvious, such as plants that have parts that move to track the movement of the sun.
Respiration - Respiration is a chemical reaction that happens within cells to release energy from food.
Sensitivity - The ability to detect changes in the surrounding environment.
Growth - All living things grow.
Reproduction - The ability to reproduce and pass genetic information onto their offspring.
Excretion - Getting rid of waste.
Nutrition - The intake and use of nutrients. This occurs in very different ways in different kinds of living things.
What are ‘Carbohydrates’?
Most carbohydrates come from plants in the form of sugars. They are known as the energy foods, and are divided into two sub-groups.
The complex sugar that humans can digest is called starch.
It is found in plants such as potato, kumara and bananas, as well as seeds and grains.
Starch is digested more slowly than simple sugars so it is slower to release energy.
This makes it an ideal energy source for athletes.
The simple sugars such as sucrose (table sugar), glucose (lollies and sports drinks) and fructose (fruit) are our main source of energy.
They provide us with energy to move, grow and keep warm.
They are easily digested and enter the bloodstream quickly, giving us almost instant energy.
What are ‘Proteins’?
Proteins are essential for all organisms. They form the main structural part of animal cells, therefore foods high in protein usually originate from animal tissue (i.e. meat, eggs and dairy products).
Protein is required for
growth, to repair damaged tissue, control of chemical reactions (enzymes), sending messages around the body (hormones), providing an emergency energy source.
A protein molecule is made up of many smaller units called amino acids. The order and arrangement of these amino acids is different for each protein.
What are ‘Lipids’?
Lipid is the collective name for oils (liquid) and fats (solid). Generally lipid fats come from animal sources and lipid oils come from plant sources.
Lipids are required for;
making cell membranes (the outer part of a cell),
energy,for insulation - keeping us warm,
protecting the organs (i.e. our kidneys).
Eating too much lipid-rich food can be bad for you and lead to a range of health problems, such as obesity and heart disease.
A lipid molecule is made of glycerol and fatty acids. Lipids can be named according to how many fatty acids they contain. For example, a triglyceride is made up of a glycerol molecule and three fatty acids. Triglycerides are the main lipids circulating in the blood and account for almost 95% of the fat in the body.
What is ‘Digestion’?
Digestion is a term used to describe the process of breaking down large molecules into smaller soluble molecules that can be absorbed into the circulatory system for use throughout the body. The mammalian body contains a number of organs collectively called the “digestive system” which is responsible for this process.
What are ‘Molars’?
Numerous, large, flat-surfaced teeth found towards the rear end of the jaw. They are used for crushing and grinding. Dominant teeth in herbivores.
What are ‘Canines’?
Pointed teeth (often called ‘eye teeth’). They are used for ripping and tearing flesh off bones and for holding onto and piercing the vital organs of living prey.
What are ‘Incisors’?
Chisel-like teeth found at the front of the jaw. They are used for cutting and removing food from its source (i.e. grass from the ground).
Describe the structure of a tooth.
The part of the tooth you see is called a crown. The rounded high parts on the top of the teeth are cusps. The hard white outer covering of the tooth is the enamel. Below the gum-line, holding the tooth in the jawbone, is the root of the tooth. You can’t see the roots. The roots are held in place by a thin layer called cementum. The inner portions of the tooth consist of the dentine, a bone-like tissue, and the pulp. The pulp is like a house for the nerves and blood vessels at the center of the crown and root.
Compare and contrast Ingestion and
Egestion.
Ingestion and egestion are both digestive processes. Ingestion is the process by which food is taken into the digestive system, whereas egestion is the process of removing undigested material from the digestive system.
Compare and contrast Ingestion and Mechanical digestion and Chemical digestion.
Mechanical digestion is the physical breakdown of food by the action of teeth and muscle movement. Alternatively, chemical digestion is the breakdown of food by the action of acids and enzymes.
Compare and contrast Absorption and
Assimilation.
Absorption and assimilation are both stages in the digestive process. Absorption is the process by which the products of digestion are transferred into the body’s internal environment, enabling them to reach the cells, whereas assimilation is the process whereby absorbed nutrients are converted into the fluid or solid substances of the body.
Compare and contrast Molars, Canines and Incisors.
Molars, canines and incisors are the three main types of teeth found in mammals. However, they differ in their structure and function. Molars are large flat teeth used for crushing and grinding, whereas canines are pointed and used for removing flesh from bone, while incisors are chisel-like and used for cutting. Canine teeth are usually absent in herbivores, but predominant in carnivores. However, herbivores usually have large flat molars, unlike the smaller pointed molars in carnivores.
