Category: My Classroom Material

Chlorophyll Fluorescence

 

Chlorophyll Fluorescence

INTRODUCTION

When a pigment absorbs light, electrons of certain atoms in the pigment molecules are boosted to a higher energy level. The energy of an absorbed photon is converted to the potential energy of the electron that has been raised to an excited state. In most pigments, the excited electron drops back to its ground-state, or normal orbit, and releases the excess energy as heat. Some pigments, including chlorophyll, emit light as well as heat after absorbing photons.
In the chloroplast, these excited electrons jump from the chlorophyll molecule to a protein molecule in the thylakoid membrane, and are replaced by electrons from the splitting of water. The energy thus transferred, is used in carbohydrate production.
This release of light is called fluorescence. Chlorophyll will fluoresce in the red part of the spectrum, and also give off heat. In this lab, you will observe this fluorescence by separating the chlorophyll from the thylakoid membrane.

MATERIALS

 

Spinach leaves Flashlight or small lab light
Mortar and pestle Test tube
Acetone Filter paper
25-mL graduated cylinder Funnel
Ring stand or funnel rack Safety goggles

PROCEDURE

1. Grind the spinach leaves using a mortar and pestle.

2. Add acetone to the ground leaves, using enough acetone and spinach leaves to get between 10 and 15 mL of extract.

3. Set up your filtering apparatus, and using proper filtering technique, filter the extract to a test tube. NOTE: Use a small amount of acetone to wet the filter paper, to hold it into place, instead of water.

4. Shine a flashlight, or other similar light source, through the test tube and extract.

5. Observe the fluorescence of the chlorophyll at a 90 degree angle to the flashlight.

 

Chordates

Chordates
All Materials © Cmassengale  

Characteristics of Chordates

  • All chordates have a notochord, dorsal nerve cord, pharyngeal pouches, & postanal tail at some time in their life
  • Notochord is a firm, flexible rod of tissue located on the dorsal side of the body that becomes part of the endoskeleton in vertebrates
  • Dorsal nerve cord is a hollow tube lying dorsal to the notochord that becomes the brain & spinal cord in vertebrates
  • Pharyngeal pouches are small outpockets of the anterior part of the digestive tract that become gills in aquatic chordates & jaws, inner ear, & tonsils in terrestrial chordates
  • Postanal tail consists of muscle tissue & lies behind the posterior opening of the digestive tract

Subphyla of Chordates

  • The Phylum Chordata  includes all of the vertebrates, as well as two groups of marine animals that lack backbones and are called invertebrate chordates
  • The phylum is divided into three subphyla, determined by the development of the notochord
  • Subphylum Cephalochordata contains about 24 species of blade-shaped animals known as lancelates that retain the notochord, dorsal nerve chord, pharyngeal pouches, and postanal tail throughout their life
  • Subphylum Urochordata  contains 2,000 species commonly called tunicates because their bodies are covered by a tough covering, or tunic
    * Called sea squirts because they shoot out a stream of water when touched
    *Sessile, barrel-shaped, filter feeding animals that live on the sea bottom
    *Adults have a pouch-like pharynx with slits
    *Adults do not have a notochord, dorsal nerve cord, or postanal tail
  • Subphylum Vertebrata is the largest subphylum in which the notochord is replaced with vertebrae
    *  Skeletons consist of bone &/or cartilage
    * Brain is protected by a cranium
    * Well developed 4 chambered heart with a closed circulatory system
    * Includes fish, amphibians, reptiles, birds, & mammals

Fish, Amphibians, Reptiles, Birds, and Mammals
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Biochemistry Quiz 2

Name: 

Biochemistry 

 

 

True/False
Indicate whether the sentence or statement is true or false.
1.
When sugar is dissolved in water, the sugar and water are chemically combined.
2.
Functional groups are side groups of carbon compounds that confer specific properties to these compounds.
 

Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.
3.
Water molecules are polar, with the
a.
oxygen side being slightly positive and the hydrogen side being slightly negative.
b.
oxygen and hydrogen sides being slightly positive.
c.
oxygen and hydrogen sides being slightly negative.
d.
oxygen side being slightly negative and the hydrogen side being slightly positive.
4.
Which of the following organic compounds is the main source of energy for living things?
a.
carbohydrates
b.
lipids
c.
nucleic acids
d.
proteins
5.
Which of these is a characteristic of enzymes?
a.
they are protein
c.
they are reusable
b.
they are specific
d.
all of these
6.
Which element is found in proteins but not in carbohydrates and fats?
a.
nitrogen
c.
hydrogen
b.
carbon
d.
oxygen
7.
Which organic molecule below is most closely related to lipids?
a.
amino acids
c.
nucleotides
b.
CH2 chains
d.
sugars
chp3_online_tutoria_files/i0100000.jpgchp3_online_tutoria_files/i0100001.jpg
             Molecule A        Molecule B
8.
Refer to the illustration above. Molecules like Molecule “B” are found in
a.
carbohydrates.
c.
nucleic acids.
b.
lipids.
d.
proteins.
9.
Which of the following is composed of fatty acids and glycerol?
a.
carbohydrate
c.
protein
b.
lipid
d.
nucleic acid
10.
This group of organic compounds includes monosaccharides:
a.
carbohydrates
c.
protein
b.
lipids
d.
nucleic acids
11.
Carbon is different from most other elements in that
a.
it has four electrons in its outermost energy level.
b.
it readily bonds with other carbon atoms.
c.
it can form single, double, or triple bonds with other atoms.
d.
it shares two electrons with another atom when it forms a covalent bond.
12.
Which of the following characteristics of water is not a result of hydrogen bonding?
a.
adhesive strength
b.
capillarity
c.
cohesive strength
d.
All of the above are a result of hydrogen bonding.
13.
Polysaccharides are
a.
carbohydrates.
c.
proteins.
b.
lipids.
d.
unsaturated fats.
14.
Enzymes involved in a chemical reaction:
a.
are used up during the reaction
b.
are decomposed during the reaction
c.
react more rapidly as the reaction progresses
d.
are not used up during the reaction
15.
Which organic compound is involved in heredity?
a.
carbohydrate
c.
proteins
b.
lipid
d.
nucleic acids
16.
Water molecules break up other polar substances,
a.
such as sugars.
b.
because of the uneven charge distribution that exists in water molecules.
c.
thus freeing ions in these substances for use by the body.
d.
All of the above
17.
When a glass is filled to the brim with water, the water appears to bulge from the sides of the glass due to
a.
capillarity
c.
adhesion
b.
thermal energy
d.
cohesion
18.
Lipids are soluble in
a.
water.
c.
oil.
b.
salt water.
d.
All of the above
19.
Which organic molecule below is classified as a carbohydrate?
a.
amino acid
c.
nucleotide
b.
CH2 chain
d.
sugar
20.
Which of the following is not an organic macromolecule?
a.
carbohydrate
c.
lipid
b.
ice
d.
nucleic acid
21.
Long chains of amino acids are found in
a.
carbohydrates.
c.
proteins.
b.
lipids.
d.
sugars.
22.
Amino acids are the building blocks of larger molecules called:
a.
cellulose
c.
fats
b.
proteins
d.
glycogen
23.
Which of the following is an organic compound?
a.
CaO
c.
C5H12
b.
H2O
d.
H2SO4
24.
All of the following are examples of carbohydrates except
a.
sugar.
c.
steroids.
b.
cellulose.
d.
glycogen.

 
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Chapter 42 AP Obj Circulation

 

 

Chapter 42   Circulation & Gas Exchange 
Objectives
Circulation in Animals
1. Describe the need for circulatory and respiratory systems due to increasing animal body size.
2. Explain how a gastrovascular cavity functions in part as a circulatory system.
3. Distinguish between open and closed circulatory systems. List the three basic components common to both systems.
4. List the structural components of a vertebrate circulatory system and relate their structure to their functions.
5. Describe the general relationship between metabolic rates and the structure of the vertebrate circulatory system.
6. Using diagrams, compare and contrast the circulatory systems of fish, amphibians, non-bird reptiles, and mammals or birds.
7. Distinguish between pulmonary and systemic circuits and explain the functions of each.
8. Explain the advantage of double circulation over a single circuit.
9. Define a cardiac cycle, distinguish between systole and diastole, and explain what causes the first and second heart sounds.
10. Define cardiac output and describe two factors that influence it.
11. List the four heart valves, describe their location, and explain their functions.
12. Define heart murmur and explain its cause.
13. Define sinoatrial (SA) node and describe its location in the heart.
14. Distinguish between a myogenic heart and a neurogenic heart.
15. Describe the origin and pathway of the action potential (cardiac impulse) in the normal human heart.
16. Explain how the pace of the SA node can be modulated by nerves, hormones, body temperature, and exercise.
17. Relate the structures of capillaries, arteries, and veins to their functions.
18. Explain why blood flow through capillaries is substantially slower than it is through arteries and veins.
19. Define blood pressure and describe how it is measured.
20. Explain how peripheral resistance and cardiac output affect blood pressure.
21. Explain how blood returns to the heart even though it must sometimes travel from the lower extremities against gravity.
22. Explain how blood flow through capillary beds is regulated.
23. Explain how osmotic pressure and hydrostatic pressure regulate the exchange of fluid and solutes across capillaries.
24. Describe the composition of lymph and explain how the lymphatic system helps the normal functioning of the circulatory system. Explain the role of lymph nodes in body defense.
25. Describe the composition and functions of plasma.
26. Relate the structure of erythrocytes to their function.
27. List the five main types of white blood cells and characterize their functions.
28. Describe the structure of platelets.
29. Outline the formation of erythrocytes from their origin from stem cells in the red marrow of bones to their destruction by phagocytic cells.
30. Describe the hormonal control of erythrocyte production.
31. Outline the sequence of events that occurs during blood clotting and explain what prevents spontaneous clotting in the absence of injury.
32. Distinguish between a heart attack and a stroke.
33. Distinguish between low-density lipoproteins (LDLs) and high-density lipoproteins (HDLs).
34. List the factors that have been correlated with an increased risk of cardiovascular disease.
Gas Exchange in Animals
35. Define gas exchange and distinguish between a respiratory medium and a respiratory surface.
36. Describe the general requirements for a respiratory surface and list a variety of respiratory organs that meet these requirements.
37. Describe respiratory adaptations of aquatic animals.
38. Describe the advantages and disadvantages of water as a respiratory medium.
39. Describe countercurrent exchange and explain why it is more efficient than the concurrent flow of water and blood.
40. Describe the advantages and disadvantages of air as a respiratory medium and explain how insect tracheal systems are adapted for efficient gas exchange in a terrestrial environment.
41. For the human respiratory system, describe the movement of air through air passageways to the alveolus, listing the structures that air must pass through on its journey.
42. Compare positive and negative pressure breathing. Explain how respiratory movements in humans ventilate the lungs.
43. Distinguish between tidal volume, vital capacity, and residual volume.
44. Explain how the respiratory systems of birds and mammals differ.
45. Explain how breathing is controlled in humans.
46. Define partial pressure and explain how it influences diffusion across respiratory surfaces.
47. Describe the adaptive advantage of respiratory pigments in circulatory systems. Distinguish between hemocyanin and hemoglobin as respiratory pigments.
48. Draw the Hb-oxygen dissociation curve, explain the significance of its shape, and explain how the affinity of hemoglobin for oxygen changes with oxygen concentration.
49. Describe how carbon dioxide is picked up at the tissues and deposited in the lungs.
50. Describe the respiratory adaptations of the pronghorn that give it great speed and endurance.
51. Describe respiratory adaptations of diving mammals and the role of myoglobin.
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