August 2006 Practice Exam

Question 1

Organelle that packages and stores proteins

Answer 1

Golgi Body

Question 2

Mitochondria

Answer 2

Deal with respiration and energy production

Question 3

What type of chemical bond occurs between DNA strands

Answer 3

weak hydrogen bond

Question 4

DNA is a molecule of what

Answer 4

Nucleotides, nitrogen bases

Question 5

Characteristics of DNA

Answer 5

Double helix
Thymine
Deoxyribose

Question 6

Steps of DNA replication

Answer 6

1. “unzip” the double helix. helicase breaks down the hydrogen bonds holding the nitrogen bases together
2. Replication fork, one strand goes in the 3’-5’ direction and becomes the leading strand, while the other is the lagging strand
3. The next processes vary by strand

Question 7

Steps of DNA replication for the leading strand

Answer 7

RNA Primer binds to DNA strand to act as a starting pont for DNA synthesis
DNA polymerase binds to the DNA strand and adds the complimentary bases
Continuous

Question 8

Steps of DNA replication for the lagging strand

Answer 8

Numerous RNA primers are made by the primase enzyme and bind at various points along the lagging strand
Chunks of DNA (okazaki fragments) are added in the 5’-3’ direction
Discontinuous (will need to be put together eventually

Question 9

Protein Synthesis

Answer 9

A succession of tRNA RNA molecules charged with appropriate amino acids and brought together with an mRNA molecule

Question 10

mRNA

Answer 10

Messanger RNA - Encodes amino acid sequence of a polypeptide

Question 11

tRNA

Answer 11

Transfer RNA - Brings amino acids to ribosomes during translation

Question 12

rRNA

Answer 12

Ribosome RNA - with ribosomal proteins, makes up the ribosomes, the organelles that translate mRNA

Question 13

Integral Proteins

Answer 13

Have specific functions unique to each one of them
Largely determine a membranes specific functions
(Carrier, channel, receptor, enzymatic…)

Question 14

Peripheral proteins

Answer 14

Often have a structural role as they help stabilize and shape the plasma membrane

Question 15

Active transport

Answer 15

Movement of molecules across cell membrane from a region of lower concentration to a region of higher concentration
Moves them against their concentration gradient
Uses ATP

Question 16

Examples of active transport

Answer 16

water moving into cells when they are placed in a hypotonic solution

Question 17

Osmotic Pressure

Answer 17

The pressure that would have to be applied to a pure solvent to prevent it from passing into a given solution via osmosis

Question 18

What hormone causes the metabolic rate of body cells to increase

Answer 18

Thyroxin - Causes metabolic rate and body heat production to increase
THYRoid gland controls the release

Question 19

Where in the digestive track does the breakdown of a substance produce maltose

Answer 19

in the stomach and mouth, made in the pancreas secreted as part of saliva

Question 20

What is a result of increased secretion by the liver?

Answer 20

An increased concentration of glycerol in the duodenum

Question 21

Steps of blood clotting

Answer 21

1. Platelet plug forms
2. Thrombin acts as an emzyme and causes fibrinogen to form long fibrin threads
3. Fibrin threads entwine the platelet plug forming a mesh-like frame work for a clot
4. This traps the red blood cells, forming a clot

Question 22

Lymphatic System

Answer 22

The network of vessels through which lymph drains from the tissues into the blood
Part of the circulatory and the immune system
Helps rid the body of toxins and materials

Question 23

Diastole

Answer 23

Period of isovolumic relaxation

Passive ventricular filling

Question 24

Systole

Answer 24

Period of isovolumic contraction

Period of ejection

Question 25

Sinoatrial node

Answer 25

The hearts natural pacemaker

Located in the upper righthand wall of the right atrium

Question 26

What happens during inhalation

Answer 26

Diaphragm contracts and moves downward which increases the space in your chest cavity
Intercostal muscles between your ribs also enlarge chest cavity as they pull your ribs upward and outward when they CONTRACT

Question 27

What part of the brain controls inhalation

Answer 27

Medulla oblongata

Question 28

Brain stem

Answer 28

controls breathing, heart rate, blood pressure and alertness

Question 29

As carbon dioxide enters the blood during internal respiration, ____ decreases

Answer 29

Water

Question 30

Medulla Oblongata

Answer 30

Continuation of the spinal cord with the skull, forming the lowest part of the brain stem

Question 31

Steps of chemical digestion

Answer 31

1. Amylase in the saliva works to start the breakdown of carbohydrates
2. Gastric juices in the stomach breakdown food into chyme
3. In the small intestine, a mix of bile, enzymes and fluids are released. Enzymes break down carbohydrates to their smallest possible pieces
4. Large intestine absorbs nutrients as needed

Question 32

Structure of arteriole

Answer 32

Tiny branches of arteries that lead to capillaries. Constrict and dilate to control blood flow
Strong, thick wall for their size, high percentage of smooth muscle
Changes speed and pressure of blood so when it reaches capillaries it isn’t pulsing.