Digestive System Flashcards
What is a cell?
The smallest unit of life Makes up all living things
What is a tissue?(Give an example)
A group of similar cells working together
i.e. group of nerve cells makes a nerve (tissue)
What is an organ?(Give example)
A group of tissues working together
i.e. muscle tissue and nervous tissue both needed in the heart
What is an organ system?
A group of organs working together to carry out an essential bodily function
What is a nutrient?
A substance which is needed for an organism to survive and be healthy
What are the 3 macronutrients?
Fats (lipids)
Protein
Carbohydrates
What is the function of the digestive system?
To break down and absorb nutrients from food
What is the role of enzymes in the digestive system?
Speed up the breakdown of macronutrients (fats, proteins and carbs)
What enzyme digests fats (lipids) and what is produced?
Enzyme: Lipase
Products: Fatty acids
and glycerol
What enzyme digests protein and what is produced?
Enzyme: Protease
Products: Amino acids
What enzyme digests starch and what is produced?
Enzyme: Amylase
Products: Glucose
What 2 organs produce all 3 digestive enzymes?
Pancreas
Small intestine
What organ produces only amylase?
Salivary glands
What organ produces only protease?
Stomach
Explain the effect of temperature on enzyme activity?
Increasing temperature, increases enzyme activity because there is more kinetic energy and more collisions between molecules
After the optimum temperature, enzyme activity decreases because the enzyme is denatured
Explain the effect of pH on enzyme activity?
• Each enzyme works best at optimum pH
• Increasing or decreasing pH, enzyme activity decreases because the enzyme is denatured
What is the active site?
Where the substrate joins to the enzyme
Describe what happens when an enzyme is denatured?
The enzyme changes shape and can no longer function
What jobs do enzymes have outside the digestive system?
Speed up other reactions such as
• Building large molecules from small
• Respiration
• Photosynthesis
The small intestine is an exchange surface. What does this mean? Give 3 examples.
Exchange surfaces increase the rate of absorption of nutrients into an organism
Roots in plants (water)
Small intestines (glucose, amino acids,
fatty acids, glycerol)
Lungs (oxygen)
How is the small intestine adapted for its function?
Villi make large surface area
Good blood supply
Walls one cell thick
Where is bile made?
Liver
Where is bile stored?
Gall bladder
Describe the function of bile.
To speed up fat digestion by lipase
Explain how bile speeds up fat digestion by lipase in the small intestine.
Neutralises stomach acid which creates optimum
pH for lipase to work
Breaks down fat into
smaller droplets (emulsifies) so it has a larger surface area
Name the digestive system organs
mouth, esophagus, stomach, small intestine, pancreas,gall bladder,liver,large intestine, rectum and anus
What is an Enzyme?
Biological catalyst:
Speeds up reactions without getting changed or used up in the reaction itself
