Bio 12				Final Exam			Name: _______________

Part I - Give definitions for each of the following terms:

glycolysis:


glycosuria


fermentation


homologous:


gene


corpus luteum


endometrium


amniocentesis


homeostasis


somatic nerve


synaptic cleft


myelin sheath


refractory period


 
Part II - Complete the following sentences with the word or words necessary.


6. The purpose of folds in the surface of the cerebrum is to ________________________.

8.  An example of a neurotransmitter is ___________________.

12. The change in living organisms over time is called _____________.

13. Dura mater is the name given to _____________________.

14. The temporal lobe of the brain is involved with _______________________.

15. The axon carries impulses _______ the cell body ______ the end brush.

16. The largest region of the brain is called the _____________.

17. Information about the environment is brought to the CNS by ________ neurons.

1.  The primary energy source for the cell is _____________a polysaccharide stored in the liver and muscles. 

2.  Organisms that emerged during the first billion years 
    could fuel their metabolism only by ATP generated by glycolysis

3.  The Krebs Cycle is another name for ______________.

4.  In some animal cells and bacteria, pyruvic acid is fermented to form __________, which can           accumulate and cause muscle cramps.


5.  Yeast cells are used in the making of beer and bread, since the products of fermentation are              _________ and _________.

 
6.  Mitochondria are called the Apower houses@ of the cell, because they can convert the products       of glycolysis to ATP in the presence of _________.

7.  NAD and FAD are hydrogen acceptors or ____________.

8.  For each glucose molecule oxidized, the electron transport chain produces ___ molecules ATP.

9.  The law of independent assortment was stated first by __________.

10. Genes are closely linked in order to increase ___________________.

11. Storage of hereditary information takes place in the _______________-.

1.	An endocrine gland requires/does not require _______________ ducts.

2.	Hormones regulate basic drives and _______________.

3.  Two endocrine glands are the _____________ and ___________.  

4.  Hormones act by ___________ ordinary cellular processes.

5.  The Fallopian tube is another name for the ______________.

6.  The primary source of estrogen is the _______________.

7.  The purpose of FSH is to _______________________.

8.  A decline in progesterone and estrogen results in less oxygen reaching the  __________.

9.  The primary source of estrogen is the ____________.

10. The central nervous system consists of  ________________________.

11. The purpose of the autonomic nervous system is to ________________________.

12. Information about the environment is brought to the CNS by ________ neurons.

13.  The pancreas is considered to be an endocrine gland because ______________________.

14. Type II (late onset Diabetes) is best treated with sulfonamides because _________________.

15. Hormones are organic substances:  proteins, amines or ___________.

16. NAD and NADP function as hydrogen ___________.

17. During the light reaction of photosynthesis, ________ is added to ADP to produce ______.

18. The dark reaction (carbon fixation reaction) of photosynthesis requires _________ and RDP to form an unstable sugar.

19. One glucose molecule by the process of cellular respiration can produce ______  molecules of ATP.

The source of the oxygen produced in photosynthesis is:
a)	carbon dioxide
b)	carbon dioxide and water
c)	water
d)	glucose

Cellular respiration takes place in the:
a)	Golgi bodies
b)	ribosomes
c)	mitochondria
d)	vacuoles

Carbon dioxide molecules are used during photosynthesis in the:
a)	photo phase
b)	light reaction
c)	light phase
d)	dark phase

The most important function of  cholorphyll  is to:
a)	trap hydrogen
b)	absorb light
c)	split carbon dioxide
d)	trap carbon dioxide

Energy  released form the oxidation of glucose is trapped in:
a)	carbon dioxide
b)	RNA
c)	Hydrogen
d)	ATP

Enzymes and hormones are:
a)	proteins
b)	fatty acids
c)	carbohydrates
d)	monosaccharides

Water molecules are split in photosynthesis during the:
a)	dark phase
b)	dark reaction
c)	synthetic phase
d)	photo phase

Mendel chose garden peas for his experiments because they differ in definite characteristics and:
a)	they lived a long time
b)	much work had been done with them before
c)	they were easy to cross-pollinate
d)	they were all the same size

If gene A prevents the expression of gene a, we say that gene A is:
a)	recessive
b)	dominant
c)	homozygous
d)	lethal

The blood type that is always evidence of a heterozygous condition is:
a)	AB
b)	A
c)	B
d)	O

Any difference existing between identical twins are due to:
a)	their genes
b)	their environment
c)	their mother's genes
d)	their father's genes

New characteristics can appear suddenly as a result of:
a)	mass selection
b)	mutation
c)	line breeding
d)	inbreeding




Part III: Multiple Choice Circle the letter of the correct choice in each of the following:

1. Not a possible combination of an AaBB x Aabb cross
a) AaBb
b) AABb
c) AABB
d) aABb
e) AabB


3. With the exception of red blood cells that do not have nuclei, your sex cells, and a few cells with random mutations that have occurred in your lifetime, the living cells in your body have _________ as the fertilized egg cell from which you developed.
a) the same genetic information
b) the same cell membrane receptor proteins
c) the same functions
d) all of the same enzyme reactions
e) the same size and shape


4. Which of the following would result if the sodium-potassium pump of a neuron was inoperative?
a) The movement of chloride ions would produce an action potential.
b) An impulse would travel from the axon to the dendrites of the neuron.
c) The rate of transmission of the impulse would greatly increase.
d) The rate of ATP synthesis would increase.
e) An action potential would not occur.


In humans primary oocytes are located in the 
a) cervix
b) uterus
c) corpus luteum
d) oviduct
e) ovary

The Krebs cycle is part of the process of ___________, which occurs in the __________ of _________- cells.
	1			2		3
a)	photosynthesis            chloroplasts          plant
b)	respiration                   cytoplasm            animal
c)	biosynthesis                chloroplasts          plant 
d)	decomposition            mitochondria        prokaryote 
e)	respiration                   mitochondria        plant and animal cells

The result of regular aerobic exercise is an increase in muscle tone, strengthening of the heart muscle, and increase in lung capacity, and a loss of weight in the form of:

a)	water lost as sweat
b)	heat
c)	glucose
d)	pyruvic acid
e)	carbon dioxide

One of the main functions of ATP in your body is to:

a)	produce heat
b)	convert oxygen and hydrogen to water
c)	produce CO2
d)	provide chemical energy for biosynthesis
e)	assist in the fixation of  CO2

With the execption of red blood cells that do not have nuclei, your sex cells, and a few cells with random mutations that have occurred in your lifetime, the living cells in your body have _____________ as the fertilized egg cell from which you developed.

a)	the same genetic information
b)	the same cell membrane receptor proteins
c)	the same functions
d)	all of the same enzyme reactions
e)	the same size and shape


Part IV - Answer the following with several sentences for each:

Describe two stages in cellular respiration.

3.  What happens in the matrix of mitochondria?


4.  What happens during cellular respiration?


Part V - Using properly labelled diagrams, describe ANY ONE of the following in detail.


1.  Using a properly labelled diagram, describe the transmission of a nerve impulse.


 
2.  Using a properly labelled diagram, explain the path of a spinal reflex.


 
2.  Using a properly labelled diagram, describe the structure and function of the reflex arc in              higher vertebrates. 





III.  Using a properly labelled diagram, describe the ovarian cycle.






a) Using the disease Diabetes mellitus as an example, explain how negative feedback  maintains a proper level      of hormones.   Refer to each of these hormones by name, describe what each does and its source.

 
b) Discuss how feedback mechanisms regulate the uterine cycle in a nonpregnant human  female.  Refer to specific hormones and their actions.


c) How does the autonomic nervous system of vertebrates help them survive?  Explain with reference to the effect it has on five organs of the human body.
.


 

Cellular respiration is a complex series of chemical reactions that occur in both the cytosol and the mitochondria of a cell.  A mitochondrion consists of a pair of membranes surrounding an interior, the matrix.  The innermost membrane forms many inward-facing folds, the cristae, which greatly increase the amount of membrane that can be packed within the mitochondrion.  The similarity of a mitochondrion to a tiny cell suggests that the mitochondria may have evolved from independent beings that invaded larger cells as parasites.

The primary energy source for the cell is glucose (C6H12O6) which arises principally from the hydrolysis of glycogen, a polysaccharide stored in the liver and muscles.  From the liver, glucose may be carried by the circulatory system to target cells which it enters easily by membrane.  Upon arrival in the cytosol, glycolysis takes place.  Its potential energy is thereby increased; it also acquires a negative charge which prevents its escape from the cell.

The energy that enters a cell in an energy-rich fuel such as glucose must be used to synthesize ATP molecules in order to be used effectively.  The process begins with a series of reactions known collectively as glycolysis.  These reactions must have evolved a very long time ago since they exist, in identical form, in all living things.  Organisms that emerged during the first billion years of the development of life on earth used no atmospheric oxygen to fuel their activities.  They could fuel their metabolism only by ATP generated by glycolysis, which is thought to have been one of the earliest of all biochemical processes to have evolved.



Adenosine triphosphate (ATP) is a complicated molecule consisting of portions of a number of simpler molecules linked by covalent bonds.  The Abuilding blocks@ are a nitrogen-containing base (adenine), a five-carbon sugar (ribose), and three molecules of phosphoric acid.  The energy resides at one of two Ahigh energy bonds@ between the remnants of phosphoric acid molecules (phosphate groups).   ATP can absorb energy and then release it again where and when it is needed.  It is like a rechargeable battery.  To release it the ATP reacts to form a molecule that has 2 phosphate groups.  Typically, the end phosphate group is transferred to the reactant and adenosine diphosphate (ADP) is left over, which is an energy acceptor.

ATP ----- ADP + P + energy     

This reaction goes in both directions and this is the way cells control and direct their energy use for such things as active transport of materials across plasma membranes.  
 

Fermentation occurs in the cytoplasm of yeast cells and 2 molecules of ATP are produced.  Fermentation converts pyruvate to acetaldehyde then to ethanol and in the process regenerates the NAD molecule.  The NAD then cycles back into glycolysis and maintains the production of ATP.  Special enzymes in the yeast cells extract carbon dioxide and ethanol remains.  Yeast cells have mitochondria and can switch to aerobic respiration when oxygen is present.

C6H12O6 + 2ADP + 2P  ---- 2CH3CH2OH + 2CO2 + 2ATP


Some animal cells and bacteria ferment pyruvic acid to lactic acid when oxygen is not available. Lactic acid will accumulate in muscles during strenuous exercise, if sufficient amounts of oxygen are not delivered to the tissues.  This results in muscle cramps.

C6H12O6 + 4ADP + 4P ---- 2CH3CHOHCOOH + 4ATP



During the anaerobic phase of cellular respiration (glycolysis) the 6-carbon glucose is split into two 3-carbon molecules of PGAL (phosphoglyceraldehyde).  A coenzyme NAD (nicotinamide adenine dinucleotide) accepts an H proton and its electron from each of the PGAL molecules, and is converted to NADH, making 2PGA (phosphoglyceric acid) which in turn is converted to 2pyruvic acid molecules by the action of other enzymes.  Being an even stronger electron acceptor than NAD, pyruvic acid pulls hydrogen and its electron away form NADH.  In turn, the NADH releases hydrogen and its electron to pyruvic acid, thereby restoring NAD. This results in the production of  2ATP molecules.  While glycolysis is able to meet the demands of simple organisms, more complex organisms need additional reactions to harness the energy contained in the pyruvate and NADH molecules.
 


In the presence of oxygen unstable 3-carbon pyruvic acid breaks down to form 2-carbon acetic acid.  The two molecules of pyruvic acid produce 4ATP. However, 2ATP are used to energize the glucose, so a net yield of 2ATP is produced by this process. This occurs in the matrix of the mitochondrion. The acetic acid becomes attached to coenzyme A to form a complex called acetyl coenzyme A (acetyl coA).   This requires the removal of carbon dioxide.  Hydrogen and its electron are removed from pyruvic acid by NAD.  
.  
(If adequate amounts of oxygen are available, the H atom moves through the electron transport system and additional ATP is formed.)  


In the Krebs Cycle (Citric Acid Cycle) the 2-carbon of acetic acid combines with a 4-carbon molecule to form a 6-carbon molecule, citric acid.  In a further series of reactions occurring in a cyclic fashion, water is added at two more points; hydrogen is removed and carbon dioxide is formed.  Eventually, all that remains is the original 4-carbon molecule, which is thus regenerated in the cyclic process.  For each molecule of glucose oxidized, two molecules of ATP are synthesized.

 

The hydrogen atoms removed during the Krebs Cycle in the matrix are transferred, either directly or via NADH2 to the electron transport chain (cytochrome enzyme system) within the inner mitochondrial membrane. The first step in this chain is a flavoprotein to which is bound to the oxidation-reduction coenzyme, FAD(flavin adenine dinucleotide).  This FAD accepts the hydrogen atoms and in doing so becomes reduced.  These atoms are split into hydrogen ions and electrons.  Each electron is transferred sequentially along the cytochromes, during which ATP is synthesized.  For each molecule of glucose oxidized, the electron transport chain produces 34 molecules of ATP.  Finally molecular oxygen binds with the terminal cytochrome, cytochrome oxidase, which then combines two hydrogen atoms and their electrons to form water.  This resulting water can be removed by the kidneys. Without a constant supply of oxygen, the electrons could not be passed down the chain of oxidizing agents, and aerobic respiration would stop.  Resulting ATP is transported from the mitochondrial matrix and diffuses into the cell cytosol. 

It is interesting that the only enzyme in cells that works with oxygen is cytochrome A3 which combines 2 protons, 2 electrons. and molecular oxygen to form water.


The overall reaction:

C6H12O6 + 6O2 + 6H2O ---- 6CO2 + 12H2O + 36ATP (heat)

The energy given off in the process of respiration is very intense.  The energy and heat released by breaking down glucose is absorbed and controlled by the cell, using the ATP to ADP cycle.