Systems Flashcards
What is the primary function of the digestive system?
The digestive system breaks down food into soluble molecules (like glucose, amino acids, and fatty acids) that can pass through cell membranes. These smaller molecules are absorbed into the bloodstream via the small intestine and are then transported by the circulatory system to various parts of the body for energy, growth, repair, and other functions.
What are the four categories of macromolecules (essential nutrients)?
- Carbohydrates
- Lipids
- Proteins
- Nucleic Acids
What are carbohydrates primarily used for?
Provides short/long term energy storage for organisms.
What is the ratio of hydrogen to oxygen in carbohydrates?
2 Hydrogen, 1 Oxygen, per 1 Carbon (2:1:1).
Define monosaccharides.
Simple sugars that contain 1 sugar molecule.
Give two examples of monosaccharides.
- Fructose
- Glucose
What are disaccharides?
Carbohydrates composed of 2 sugar molecules.
List three examples of disaccharides.
- Maltose
- Sucrose
- Lactose
What are polysaccharides?
polysaccharides are large, complex carbohydrates made up of many monosaccharide (simple sugar) units bonded by glycosidic linkages
What is the function of starch in plants?
Stores energy in plants.
What is the primary function of glycogen? And where is it found?
Glycogen is a short-term energy storage molecule. It’s made from excess glucose and stored in the liver and muscles.
- Stores energy in animals
- polysaccharide made
up of glucose units - short term energy
- equivalent to plant’s starch
What are lipids and their solubility?
They are fatty compounds, and they are insoluble in water.
- help form cell membranes
- stores long term ENERGY
What is the basic structure of lipids?
A molecule of glycerol attached to fatty acid chains.
What are the functions of lipids?
- Store long term energy
- Provide materials to build cell membranes
- Cushion/insulate internal organs
What are the main functions of proteins? [5]
- Provide structure and support for blood cells, body tissues and muscles
- Aid in muscle developments, such as contraction
- Act as catalysts to speed up chemical reactions (=enzymes)
- Provide immunity against infection
- Transport ions in cell membranes
List some examples of proteins.
- Hemoglobin
- Insulin
- Collagen
- Antibodies
- Enzymes
What is the role of enzymes in digestion?
They act as catalysts that speed up the rate of chemical reactions
What are nucleic acids responsible for?
Directing growth and development of all organisms using chemical code.
Name the two types of nucleic acids.
- RNA (Ribonucleic acid)
- DNA (Deoxyribonucleic acid)
What process breaks down macromolecules in the body?
Hydrolysis.
What is hydrolysis?
A process where water molecules are added to macromolecules, breaking chemical bonds.
What are the three main types of digestive enzymes?
- Carbohydrase (amylase is a type of carbohydrase)
- Lipase
- Protease
What does carbohydrase do?
Breaks down carbohydrates into simple sugars.
What is the product of lipase digestion?
Glycerol molecules and fatty acids.
What does protease break down?
Proteins into amino acids.
What is the function of nuclease?
Breaks down nucleic acids into nucleotides.
What are the four stages of food processing?
- Ingestion
- Digestion
- Absorption
- Elimination
What is the alimentary canal?
A digestive tract that is a long open tube from mouth to anus.
What is mechanical digestion?
Physically breaking down food into smaller pieces.
What is chemical digestion?
Breakdown of macromolecules by enzymes.
What is bolus?
The soft mass produced after chewing food.
What is peristalsis?
Wave-like muscular contractions that push food down the esophagus.