Post on 19-Jan-2016
Basic Elements of Life
Remember: CHNOPS
C = Carbon H = Hydrogen N = Nitrogen
O = Oxygen P = Phosphorus S = Sulfur
Four Macromolecules: 1. Carbohydrates
Four Macromolecules:2. Lipids
Four Macromolecules: 3. Proteins
Polymer
• Many molecules• More than one
subunit
• Example: Beads making up a necklace
Monomer
• Single molecule• One subunit
• Example: Single bead for a necklace
Carbohydrate• Also known as:
Sugars and starchesElements present:
• How many of each element are present?
C, H, O
C=6, H=12, O=6Ratio – 1:2:1
Monomer of a Carbohydrate
Simple Sugar or Monosaccharide
Type of Carb: Monosaccharide
• Explanation: One sugar / Simple Sugar
• Example: Glucose or Fructose
Carbohydrate Functions #1
• Immediate
energy source
• Burn quickly
Example of a Polysaccharide
Starch: Stored Energy in plants
Lipids Function #1
Long term energy storage
Positive Test: Grease Spot
Protein
• Elements present:
C, H, O, N, and sometimes S
R is the point of attachment for
structures that make each amino acid
unique
Protein PolymerProtein: Amino acids are held together by
peptide bonds
Protein Monomers
Amino Acid
Protein Structure
Proteins fold and fold and fold….
Proteins Function #1
Make up the structure and function of muscles
Proteins Function #2
Provides structure in hair, nails, and skin
Proteins Function #2-cont.
Provides structure feathers and hooves
Monosaccharides include glucose, fructose, galactose, deoxyribose, and ribose. A single unit of sugar, monosaccharides are the smallest carbohydrates.Glucose, a 6-carbon sugar (hexose) is the sugar in our blood. Fructose, the sugar that sweetens fruit, and galactose, the sugar found in milk, have the same chemical formula as glucose and are therefore isomers of glucose. Isomers have the same composition but a different arrangement of their atoms and have different properties.
Disaccharides include sucrose, lactose, and maltose. Two monosaccharides are joined together by dehydration synthesis to form a disaccharide molecule. Sucrose (table sugar) Glucose + fructose = sucrose + water Lactose (milk sugar)Glucose + galactose = lactose + waterMaltose (malt sugar)Glucose + glucose = maltose + water
Polysaccharides include starch, cellulose, and glycogen. These long, chain-like polymers make ideal storage products due to their insolubility. Starch is the storage molecule synthesized from glucose by plants. Cellulose, which is also synthesized by plants for cell wall construction, is indigestible because we lack enzymes for it. Cellulose provides fiber to promote peristalsis. Glycogen is the carbohydrate storage molecule found in muscle and liver cells. When blood sugar levels drop, liver cells hydrolyze glycogen and release glucose to the blood.
What is homeostasis?
The process of keeping the internal environment of the body stable while the
outside world changes
HomeostasisThe ability of an organism to adjust its internal environment to keep it stable.
Homeostasis is maintained by Feedback MechanismsThink of your thermostat at home: when the temperature drops, the heater turns on. When the temperature gets too hot, the A/C turns on.
One way an organism maintains homeostasis is by responding to its environment.
How do worms respond to their environment?
TranspirationThe upward movement of water from the roots to the leaves.
As water is lost form the outer leaf tissues, water then moves in the water deficient cells from adjacent cells. This osmotic ripple effect occurs backwards from the leaves to the roots.
Water is lost through the stomata, when they are open.
More than ninety percent of the water entering a plant evaporates into the atmosphere. A mature corn plant will transpire about fifteen liters of water per week
What factors affect transpiration?Light has a major effect on plants. During photosynthesis, the stomata must be open to allow CO2 to enter the leaf. Open stomata also allow a higher rate of transpiration.
Plants begin to wilt during times of water stress. During water stress, low turgor pressure leads to closing of the stomata. Closing of the stomata will end photosynthesis due to a lack of carbon dioxide entering the plant. This slows the plant’s metabolism.
Turgor is a measure of water pressure in the plant
Plant Responses: Phototropism*
Plants response to light.
Leaves will bend toward the light to maximum photosynthesis.
Auxins are a family of hormones found in plants. Auxins are mostly made in the tips of the shoots and roots, and can diffuse to other parts of the shoots or roots. They change the rate of elongation in plant cells, controlling how long they become.
Gravitropism
Positive Gravitropism: Roots grow down
Negative Gravitropism: Stems grow against gravity
Settling of dense particles (organelles called amyloplasts) in specialized cells causes Auxins to change the way that side of plant grows
ThigmotropismPlants response to touch
In some plants, massive amounts of plant hormones (auxins) are generated when the plant comes in contact with something solid. These auxins can cause the plant to coil, to grow new tendrils, suckers, or even trigger movement.
What is homeostasis?The process of keeping the internal
environment of the body stable while the outside world changes
HomeostasisThe ability of an organism to adjust its internal environment to keep it stable.
Homeostasis is maintained by Feedback MechanismsThink of your thermostat at home: when the temperature drops, the heater turns on. When the temperature gets too hot, the A/C turns on.
Homeostasis:Maintaining blood sugarNegative Feedback Loop• When blood
sugar is too high, liver converts glucose to glycogen (for storage)
• When sugar is low, liver breaks down glycogen and releases glucose
Homeostasis is maintained by Feedback MechanismsThink of your thermostat at home: when the temperature drops, the heater turns on. When the temperature gets too hot, the A/C turns on.
When a change needs to happen -Positive FeedbackFor each change, a response occurs that increases the change A ripening banana releases a plant hormone ethylene Ethylene accelerates the ripening of unripe fruit in its vicinity, so nearby fruit
also ripens, releasing more ethylene. All the fruit quickly becomes ripe together.