Download Macromolecules of Life – Lecture 1

Biology – Nutrient Cycles – Cowan/‘03
Macromolecules of Life – Lecture 1
All Life is composed of Four Basic Molecules:
I.
Four Macromolecules
Macromolecule Examples
Monomers Jobs
 Store Genetic
DNA;
Nucleotides
Information
Nucleic Acids RNA
 Instructions
to make
proteins
 Building
Enzymes;
blocks of
Proteins
Rhodopsin; Amino
cells.
insulin
acids
 Control
chemical
reactions
Sucrose;
 Energy
fructose;
Monosource for
Carbohydrates Glucose
saccharide
cells
 Stored
energy.
 Build
membranes
Fats
Bilayer
Glycerol
 Stored energy
VI.
Macromolecule Summary
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Biology – Nutrient Cycles – Cowan/‘03
In the Table below: Write Yes or No
CARBOHYDRATES
FATS
PROTEINS
NUCLEIC ACIDS
Monomers
Carbon
Present
Hydrogen
Present
Oxygen
Present
Nitrogen
Present
2(H):1(O)
Carboxyl
Group
Amino
Group
Hydrocarbon
tail
Hexagon?
Phosphate?
ENZYMES
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Enzymes are globular proteins. Also called biological catalysts
(Catalysts speed up chemical reactions)
How do they work?
Enzymes function by binding to one or more of the reactants
(substrate) in a reaction.
The exact location on the enzyme where substrate binding takes
place is called the active site of the enzyme.
The shape of the active site just fits the shape of the substrate,
somewhat like a lock fits a key.
In this way only the correct substrate binds to the enzyme
http://www.efhealing.com/images/enzymes.jpg
Nutrient Cycle Part I
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Biology – Nutrient Cycles – Cowan/‘03
Obtaining Nutrients Lecture
A. Autotrophs
a. Are also called Producers
b. Examples – plants, photosynthetic
bacteria,etc
c. Autrotrophs need – sunlight
B.
Heterotrophs
a. Are also called Consumers
b. Examples – rabbit, deer, etc.
c. Heterotrophs need: food
C. Photosynthesis and Cellular Respiration
a. Photosynthesis uses light energy to
construct simple sugars. Occurs in
the Chloroplast of plants!!
+
+
i. The requirements for photosynthesis:
Sunlight, Carbon Dioxide and water
b. How do plants do this?
photon of light strikes pigment (chlorophyll) causing
electron in an atom to become excited.
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The excited (energized) molecule can pass the energy to
another molecule or release it in the form of light or heat.
Thylakoids are disk-like structures stacked together in larger
structures. Chlorophyll and carotenoid pigments are located
in the membranes of the thylakoids.
Light reactions - require light and take place in the
thylakoid membrane. They convert ADP and NADP
(electron carriers) into ATP and NADPH (energy released)
needed to produce glucose in the dark reactions. Electrons
are repeatedly gained or lost.
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Chlorophyll in plants absorb light most efficiently
faculty.clintoncc.suny.edu/faculty/Michael.Gregory/files/Bio%20101/Bio%20101%20Lectures/Photosynthesis/photosyn.htm
Dark reactions – no light needed. Uses the energy of ATP
and NADPH to create sugar
Notice how the equation for photosynthesis relates to the
reactions shown in the diagram below.
6CO2 + 6H2O + Energy ® C6H12O6 + 6O2
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c. Cellular Respiration
i. The process in the mitochondria where
simple sugars are “burned” to produce
energy (in the form of ATP). Occurs in
PLANTS AND ANIMALS!
ii. Simple formula for Cellular Respiration:
ADP + PI
+
ATP (Energy)
Enzymes
+
Mitochondria supply all of
the usable energy for Plants
(autotrophs) and Animals (heterotrophs)
iii.
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Nutrient Cycle Part II
Leaf Structure
Or How Autotrophs capture nutrients
A. Leaf Diagram
a. Cuticle – thick, waxy coat (cutin)that
protects plant from loss of water and
penetration by disease – part of the
epidermis
b. Epidermis – on the top and bottom layer of
the leaf (skin), protects leaf tissue
c. Palisade Layer – the dense upper layer that
contains the chloroplasts
d. Stomata – opening in the leaf (most in
lower epidermis)
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e. Spongy Layer – lower layer that contains
more air space and chloroplasts
f. Guard Cells – protect the openings called
the stoma in the leaf and regulate the
passage of water, oxygen, and carbon
dioxide through the leaf
g. Vein – through petiole (part attached to
stem)
i. Xylem – transports water, minerals and
hormones
ii. Phloem – transports sugar, oxygen and
hormones
h. Chloroplasts - to produce glucose from
carbon dioxide and water by using light
energy.
i. Chlorophyll – green pigment required to
convert light energy into chemical
energy
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B.
Remember, Autotrophs make their own organic
nutrients (simple sugars). How do plants do this?
a. Enzymes speed the necessary chemical reactions and
give organisms the ability to control how much,
where, and when these reactions occur.
b. Glucose is coupled together into starch in the roots
of plants for storage.
c. The enzyme for this reaction is called: Sucrase
d. The chemical reaction that occurs is a Dehydration
Synthesis, draw the structures of two glucose
molecules being joined to create a disaccharide (see
Lecture page one):
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Nutrient Cycle Part III
Digestive System Lecture
Or How Heterotrophs capture nutrients
Label the Human Digestive System, we will use humans as a model for
how Heterotrophs obtain nutrients
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A. Function of Digestive Components
Part Name
Function
A
Salivary
a. Secrete enzyme amylase
Glands
(breaks down carbs)
b. cover food to produce bolus
(Mucous lubricates food)
B
C
D
E
F
Tongue
a. moves food side to side to be
chewed and keeps between teeth
b. moves bolus to back of throat
c. closes off mouth when
swallowing
Trachea
a. wind pipe
b. protected by epiglottis during
swallowing (covering)
Esophagus Food to the stomach by peristalsis
Liver
a. produces and secretes bile
which emulsifies fats
b. detoxifies blood
c. stores glycogen (animal form of
starch)
d. Reduces/neutralizes acids
e. bile breaks up fats
Gall
Stores bile
Bladder
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G
H
I
J
K
L
Stomach
a. churn/mix food
b. digestion of proteins starts here
c. Gastric juice is acidic (HCl)
and contains pepsin (enzyme to
digest proteins)
d. Gastrin (hormone) stimulates to
release of gastric juice
e. vomiting-reverse peristalsis
f. pyloric sphincter controls
opening and end of stomach
Bile Duct A duct or tube from gall bladder
to small intestine
Duodenum Most of the digestion begins here
(proteins, fats and carbs)
Pancreas a. produces powerful digestive
enzymes
b. Produces and secretes insulin –
important in regulating blood
sugar levels
Pancreas A duct or tube from pancreas to
Duct
small intestine
Small
a. 20 – 30 feet long
Intestine b. parts of sm. Intestine are:
duodenum – listed above
jejunum – has folds of skin called
the brush border membrane.
ileum – selective absorption of
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O
some nutrients. What remains is
liquid stool
c. Final digestion occurs here
d. food is absorbed in simplest
forms – amino acids, fatty acids,
glycerol
e. Villi – small finger like projects
that contain vessels to absorb food
Appendix Vestigial organ – “dead end” May
at one time have aided in
digestion of cellulose but has no
function today
Large
a. Parts are: Cecum – large
Intestine
entrance controlled by a sphincter
(colon)
that protects the small intestine
from the large intestines
concentrated bacteria, Ascending
colon – upwards, Transverse
colon – across, descending colon
– down, sigmoid colon – end
b. reabsorbs water
c. Some solid wastes are stored
before they enter rectum
Rectum
Stores solid waste until full.
P
Anus
M
N
Controlled by sphincter muscle by
peristalsis.
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B.
Digestive Processes
Process
Explanation
Takes food in – mouth
Muscular contractions
along digestive tractesophagus  small and
large intestine
Absorption Taking of digested food
into blood stream
Ingestion
Peristalsis
Dot Color
Blue
Yellow
Green
Occurs in Sm. Intestine
Storage
Animal “starch” stored as Red
glycogen in liver
Elimination Solid waste eliminated
Brown
from large intestine
Mechanical Physically chewing-mouth Orange
Digestion
Churning action-stomach
Chemical Starts carbohydrate
Purple
Digestion breakdown in mouth
Uses
enzymes
Starts protein breakdown
in stomach
Carbohydrates, proteins,
and fats are fully digested
in Sm. Intestine
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C.
Types of Food (Think Macromolecules)
Food Type
% Diet Purpose
Digestive End
Product
Fats
<30% Store energy
Glycer0l +
3 fatty acids
Carbohydrates 55%
Absorb Bitamins
(A, D, E, K)
Protect organs
Energy source
Absorption of all
food types
Proteins
Glucose
(other
monosaccharides)
Fiber- moves food
through system
>15% Growth,
Amino
maintenance/repair Acids
cells
Makes enzymes
D. What happens to the Digestive End Products (listed
above)  Absorbed into blood and delivered to cells
and organs
a. For Fats  used or stored
b. For Carbohydrates used for energy or stored
c. For Proteins used to rebuild/enzymes
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d. Remember organisms are very efficiently adapted
to providing the nutrients they need. The complex
process of changing one type of macromolecule into
another is very complex with any one able to change
into the other, through many steps and much energy
input.
E.
To speed Digestion organisms use chemicals and
enzymes
a. Acids
i. Gastric acid in stomach
ii. Contains HCl
b.Bile
i. Secreted by liver-stored in gall bladder
ii. Emulsifies fats (dissolves-NOT digest)
c. Enzymes – each enzyme (made of protein) is
regulated, with a special “job”
i. Jobs include
ii. Operate by “Lock and Key” approach
iii. Some examples
iv. Hydrolysis – (Breaking down polysaccharides to
create simple sugars)
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F.A Few Specific Digestive Enzymes
Enzyme Made
Acts
Purpose
Here
Here
Amylase Mouth Mouth Breaks polysacs to disacs
(digests carbs)
pancreas Sm.
Intestine
Pepsin Gastric Stomach Starts digestion of protein
glands
into amino acids
of
stomach
Rennin Stomach Stomach Coagulates (thickens)
protein in milk
Reduces fats to fatty acids
Lipase Pancreas Sm.
Intestine and glycerol (building
blocks of fats)
G. Enzymatic Digestion of food types
(Macromolecules)
a. Name the chemical process used by these enzymes
to help digest fats, carbohydrates, and proteins:
HYDROLYSIS
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b. Refer to diagrams of Macromolecules to fill in the
chart below. Use circled numbers to indicate
locations of hydrolysis.
Enzyme Location where
Number Digestive End
Hydrolysis Occurs
of H2O Product
Used
2
Glucose
Amylase
Between C—O—C
Pepsin
Peptides bonds (A.A.)
7
Amino acids
Rennin
Between monosacs
5
Glucose
Lipase
Between fatty acids
and glycerol
3
3 fatty acids
and glycerol
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H. Dietary Recommendations
2000 Cal Diet
2500 Cal Diet
< 30% Total Fat
Sat. Fat
Poly
Mono
65 g
20 g
22 g
23 g
80 g
25 g
27 g
28 g
Cholesterol
Salt
Carbohydrates
Dietary Fiber
300 mg
2400 mg
300 g
25 g
300 mg
2400 mg
375 g
03 g
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Biology – Nutrient Cycles – Cowan/‘03
Nutrient Cycle Part IV
Summary
A. How do autotrophs and heterotrophs get the substances they need?
Autotroph’s source
Substance
Heterotroph’s Source
CO2
Minerals
H2O
Simple sugars
O2
Energy (ATP)
Amino Acids & Proteins
Vitamins
Starch
Lipids (fats)
Cellulose
B. How do autotrophs and heterotrophs get the substances they need?
Summary Statement:
C. What happens to plants and animals if they don’t get the vitamins and minerals they need. See the
mineral and vitamin charts and record what happens when the following organisms do not have
adequate levels of each nutrient:
h. Animals –Iron
a. Plants – Nitrogen
i. Animals –Chlorine
b. Plants – Sulfur
j. Animals - Vitamin B1
c. Plants – Iron
k. Animals –Biotin
d. Plants –Copper
l. Animals – Vitamin D
e. Plants - Calcium
f. Animals – Potassium
g. Animals –Calcium
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