Unit D Ch.6 Flashcards
What is a macromolecule?
A very large molecule
What are the 4 main categories of macromolecules?
Carbohydrates,Lipids,Proteins, and Nucleic Acids.
What are 3 types of carbohydrates?
Simple Sugars-Monosaccharides, Disaccharides, and Polysaccharides.
What are the subunits that make up proteins?
Amino Acids
What type of bond forms when amino acids are joined?
Peptide bonds
How are macromolecules created and destroyed?
Dehydration Synthesis and Hydrolysis.
What are Vitamins and MInerals?
vitamins are organic substances, which means they’re made by plants or animals. Minerals are inorganic elements that come from soil and water, and are absorbed by plants or eaten by animals
What are enzymes?
A catalyst the breaks down proteins and fats
What do catalysts do?
Speed up chemcial reactions
Why do we need enzymes?
To help speed up chemical reactions
How do enzymes work? (active site, substrate)
Act upon substrate molecules and decrease the activation energy necessary for a chemical reaction to occur by stabilizing the transition state.
What is the difference between catabolism and
anabolism?
Anabolism is the building of complex molecules from numerous simple ones. Think of protein synthesis. Catabolism is the breakdown of complex molecules into numerous simple ones.
Where and how does food enter
our bodies?
…the mouth and then the
Esophagus
How does food move
through the esophagus?
Through wavelike contractions called
Peristalsis.
Name the structure that controls
the movement of food from the
esophagus into the stomach
esophageal sphincter
What is the name of the structure
that controls the exit of the stomach
to the small intestine?
Pyloric Spincter
What are the 3 jobs of the Stomach?
1.Storage
2.Digestion (some)
3.Pushing food into the small
intestine
Describe what happens to the
food physically and chemically,
to transform it into chyme?
Physically = broken down by
muscles contracting, highly acidic
Chemically = pepsin in gastric
juices
What are 3 ways the stomach
lining is protected from
digestion (acids)?
The stomach secretes little gastric juices
when there is no food present
Some cells secrete mucus which protects it
from the acidic nature of the stomach
The protein-digesting enzyme (pepsin) that
the stomach produces, is inactive until the
gastric juices are released
What is the function of pepsin in
the stomach?
Enzyme that becomes active
when in the presence of gastric
acids and hydrolyzes peptide
bonds
Explain why few substances are
absorbed in the stomach?
Because most substances in the
chyme have not broken down
enough
What is the job/role
of the small
intestine?
The main function of the small intestine
is to complete the digestion of
macromolecules and to absorb their
subunits.
What are the three regions of the small intestine?
1)Duodenum – an important site for chemical
digestion because it is joined to the liver and
pancreas through a duct
2)Jejunum – continues to break down food
3) Ileum – absorbs nutrients and pushes
undigested material into the large intestine
What is the structure of the
small intestine?
Vili and Microvilli
What is the structure of the
small intestine?
Vili and Microvilli
Why would these
projections (villi and
microvilli be important?
The villi and microvilli are important because they
maximize the surface area of the small intestine for
absorption
What is the process of
physical digestion in the
small intestine called?
Segmentation
What are the three accesory organs?
Pancreas, Liver and Gallbladder
What does Pancreatic Fluid contain?
1.Trypsin and Chymotrypsin – digests
proteins
2.Pancreatic Amylase – digests starch
3.Lipase – digests fat
4.Bicarbonate – neutralizes stomach acid
What does the liver do?
Makes bile