177 terms

mastering biology

What term describes the degree in which an element attracts electrons?
the tendency of an atom to attract electrons toward itself
Which term best describes two atoms when they form a bond in which electrons are completely transferred from one atom to the other?
Cation and anion
Which of the following statements is true of bonds in a water molecules?
Oxygen holds electrons more tightly than hydrogen does, and the net charge is zero
Net inputs for glycolysis
glucose, ADP, NAD+
Net outputs for glycolysis
2 ATP, 2 NADH, pyruvate
Location for glycolysis
what is converted in glycolysis
the six-carbon sugar glucose is converted to two molecules of pyruvate
there is no what in glycolysis
O2 reuptake or carbon dioxide release
net input for Acetyl-CoA Formation
pyruvate, NAD+, coenzyme A
net output for Acetyl-CoA Formation
CO2, acetyl-coA, NADH
location for Acetyl-CoA Formation
mitochondrial matrix
In acetyl-coA formation, what is oxidized and what is reduced and what is released
pyruvate (the product of glycolysis) is oxidized to acetyl-coA, with the reduction of NAD+ to NADH and the release of one molecule of CO2
net inputs for Citric Acid Cycle
acetyl-coA, NAD+, ADP
net outputs for Citric Acid Cycle
coenzyme A, CO2, NADH, ATP
location for Citric Acid Cycle
mitochondrial matrix
in the Citric Acid Cycle, what is oxidized and what is reduced and what is released
the two carbon groups from the acetyl group of acetyl-coA are oxidized into two molecules of CO2, while several molecules of NAD+ are reduced to NADH and one molecule of FAD is reduced to FADH2.
net inputs for Oxidation Phosphorylation
net outputs for Oxidation Phosphorylation
water, ATP, NAD+
location for Oxidation Phosphorylation
inner mitochondrial membrane
Oxidation Phosphorylation, what is oxidized and what is reduced and what is released
the NADH and FADH2 produced by the first three steps of cellular respiration are oxidized in the electron transport chain, reducing O2 to water and recycling NAD+ and FAD back to the first three stages of cellular respiration
the final electron acceptor of cellular respiration
How many NADH are produced by glycolysis
In glycolysis, ATP molecules are produced by what?
Substrate-level phosphorylation
Substrate-level phosphorylation for glycolysis
a phosphate group is transferred from glyceraldehyde phosphate to ATP
Which is not a product of glycolysis: pyruvate, ATP, NADH, FADH
FADH is a product of what?
citric acid cycle
In glycolysis, which starts the process of glucose oxidation
in glycolysis, there is a net gain of how many ATP
When a compound donates (loses) an electron, it becomes...
oxidized (electron donor)
When a compound accepts (gains) an electron, it becomes
reduced (electron acceptor)
In glycolysis, the carbon-containing compound that functions as the electron donor is
Once the electron donor in glycolysis gives up the electrons, it is oxidized into
compound that functions as the electron acceptor in glycolysis
the reduced form of the electron acceptor in glycolysis
In the net reaction of glycolysis, glucose (the electron donor) is oxidized into pyruvate. How?
The electrons removed from glucose are transferred to the electron acceptor NAD+, creating NADH.
Among the products of glycolysis, which compounds contain energy used by other biological reactions?
Pyruvate, ATP, and NADH
Which of these enter the citric acid cycle? Pyruvate, NADH + H+, G3P, acetyl-coA, glucose
In the citric acid cycle, how are ATP molecules produced?
Substrate-level phosphorylation
Substrate-level phosphorylation for citric acid cycle
a phosphate group is transferred from GTP to ATP
Which of these is not a product of the citric acid cycle? CO2, NADH + H+, ATP, acetyl-coA, FADH2
Which molecule is metabolized in a cell to produce energy for performing work?
what is used to produce high-energy ATP in a cell
True or false. The potential energy in an ATP molecule is derived mainly from its three phosphate groups
true; the three phosphate groups in an ATP molecule carry negative charges that strongly repel each other and give ATP a large amount of potential energy
Which process is not a part of the cellular respiration pathway that produces large amounts of ATP in a cell? Krebs cycle, fermentation, electron chain transport, glycolysis
alternative pathway for when oxygen levels are low
Which step of cellular of respiration pathway can take place in the absence of oxygen?
Into what molecules are all the carbon atoms in glucose ultimately incorporated during cellular respiration
carbon dioxide
Which stage of glucose metabolism produces the most ATP?
Electron transport and chemiosmosis
How much ATP is produced by Electron transport and chemiosmosis
How much ATP is produced by krebs cycle
How much ATP is produced by glycolysis
True or false. The reactions that generate the largest during cellular respiration take place in the mitochondria
In mitochondrial electron transport, what is the direct role of O2?
To function as the final electron acceptor in the electron transport chain
the only place that O2 participates in cellular respiration is at the
end of the electron transport chain.
How would anaerobic conditions affect the rate of electron transport and ATP production during oxidative phosphorylation
Both electron transport and ATP production would slow down
without O2, mitochondria are unable to
oxidize NADH and FADH2 produced in the first three stages of cellular respiration, and thus no ATP can be produced via oxidation phosphorylation
NADH and FADH2 are both electron carriers that donate their electrons to the electron transport chain. The electrons ultimately reduce O2 to water in the final step of electron transport. However, the amount of ATP made by electrons from an NADH molecule is greater than the amount made by electrons from an FADH2 molecule. Why?
Fewer protons are pumped across the inner mitochondrial membrane when FADH2 is the electron donor than when NADH is the electron door
In muscle cells, fermentation produces what
Lactate and NAD+
In fermentation, what is reduced and what is oxidized
pyruvate, NADH
Which of these is not one of the four major categories of tissue? Muscle, epithelium, connective, blood, nervous
Which term describes the a mechanism by which the internal conditions of an organism are kept at set values without regard to external conditions?
regulatory homeostasis
True or false. Organisms must maintain homeostasis because optimal enzyme activity is achieved within a narrow range of conditions
true; enzyme activity depends on the conditions within the cell, which must be kept within a narrow range of conditions.
Which component of the homeostatic system compares to the sensory information to a target value?
• Sensor, set point, effector, integrator
sends instructions to effector based on sensory information
Which component of a homeostatic system perceives changes in some parameter of the environment?
• Effector, integrator, sensor, set point
perceives changes of some parameters of the environment
Which of the following actions acts to warm a homeothermic body? Dilating blood vessels, shivering, panting, sweating
generates metabolic heat and warms body
o Which of the following is negative feedback?
• As a blood clot begins to form, the process of its formation gets faster and faster; after you eat, glucagon stimulates an increase in blood sugar levels; after you eat, insulin stimulates the lowering of blood sugar levels; the digestive enzyme pepsinogen is converted to pepsin by hydrochloric acid (positive feedback the more pepsin there is, the faster the pepsinogen is converted into pepsin); once labor begins, contractions increase in frequency and intensity
insulin stimulates the lowering of blood sugar levels
Homeostasis is...
Maintenance of a relatively constant and optimal internal environment
Metabolic rate is
The total amount of energy an animal uses in a unit of time
leuc- (leuk-)
Formative substance
oss- (osteo-)
Loosening/split apart
Break down
Treelike, branching
Water soluble vitamins
Vitamin B1 Thiamine, Vitamin C Ascorbic acid
Water soluble vitamins act as
cofactors in enzymes, not bonded to only one enzyme, but are used over and over again by different enzymes
Water soluble vitamins can
diffuse from enzyme to enzyme
Fat soluble vitamins
Vitamin K Menaquinone, CH3 Vitamin E Tocopherol, Vitamin D Cholecalciferol
Fat soluble vitamins important in
vision, bone formation, oxidative phosphorylation, and blood clotting
Folic acid
a vitamin that is used in reactions that transfer single-carbon units
Folic acid helps reduce the risk of
spina bifida and cleft lip
Vitamin C is involved in the formation of
amino acids and part of the collagen that forms connective tissues.
Vitamin A is absorbed from some foods like
The vitamin c accumulates on the
rods and cones
In a well-fed human eating a Western diet, what is the richest source of chemical energy is
fat in adipose tissue
Animals that migrate great distances would obtain the greatest energetic benefit of storing chemical energy as
Certain nutrients are considered "essential" in animal diets because
These animals cannot synthesize these nutrients
Folic acid supplements have become especially important for pregnant women because
Folic acid deprivation is associated with neural tube abnormalities in a fetus
What are the stages of food processing
Ingestion, digestion, absorption, elimination
A fatty acid also includes a
carboxyl group and hydrocarbon chain
When digested, proteins are broken down into
amino acids
When digested, fats are broken down into
Glycerol and fatty acids
Starch is a type of
why can your small intestine can absorb fructose without further digestion
because fructose are monosaccharides
What enzyme begins the break down of starch
Lipase and bile breaks down
starch can be broken down into the disaccharide
Protein digestion begins in the
stomach by the secretion of gastric juice
What is the main component of gastric juice?
Bile is secreted by the what and acts to emulsify what in the small intestines
liver, fats
bile is produced by the what and stored in the what
liver, gall blader
Which structure is not a part of the alimentary canal? Salivary glands, esophagus, stomach, mouth
salivary glands
True or false. One advantage of having a tube-like digestive tract is that digestion of all compounds can take simultaneously down the tract
one advantage of having a tube-like digestive tract is that
digestive processes with different requirements can be separated within the tract
True or false. The liver is a part of the alimentary tract
the alimentary tract is the
tract that food passes through from the mouth to the anus
Proteins that are consumed in the diet are absorbed as
individual amino acids following digestion
Carbohydrate digestion begins in the mouth with
salivary amylase
Free fatty acid absorption occurs in
small intestines
The lower esophageal sphincter surrounds the upper opening of the stomach. If the sphincter failed to properly constrict, there might be a problem with
Regurgitation of acidic stomach acid contents into the esophagus, commonly called "heartburn
The large surface are of the gut directly facilitates
fat digestion yields fatty acids and glycerol, whereas protein digestion yields amino acids. Both processes
Add a water molecule to break the bond
Carbon dioxide enters the blood at the
Capillaries of the head, forelimbs, abdominal organs, and hind legs
The what have the thinnest walls
The capillaries have the thinnest walls. why?
the thin walls facilitate gas exchange
Blood pressure is highest where
Arteries carry blood
Blood returns to the heart via the
Pulmonary veins
Pulmonary veins
carry oxygenated blood from the lungs to the left atrium
From the pulmonary veins, blood flows to the
left atrium
From the anterior vena cava, blood flows to the
right atrium
From the capillaries of the abdominal organs and hind limbs, blood flows to the
posterior vena cava
What is the function of the circulatory system
It brings the transport liquid into close contact with the cells in the body
Why do circulatory systems of land vertebrates have separate circuits to the lungs and to the rest of the body
The large decrease in blood pressure as blood moves through the lungs may prevent efficient circulation through the rest of the body
the pulmonary circuit is the what circuit to the lungs and the systematic is the what circuit to the rest of the body
low-pressure, high-pressure
flaps of tissue that close when the ventricles contract to prevent the backflow of blood into the atria and also when ventricles relax to prevent the backflow of blood from exiting vessels to the ventricles
What happens during diastole
The atria and the ventricles are relaxed and blood flows into atria
the relaxation phase of the cardiac cycle during which the chambers of the heart are relaxed and blood can enter them passively
Which event occur during the systolic phase of cardiac cycle?
The ventricles contract, carrying blood into the aorta, and blood flows into the relaxed atria
systolic pressure
peak pressure
true or false. blood in the right chamber cannot enter the left chamber without passing through the lungs
Which of the following develops the greatest pressure in the mammalian aorta
Systole of the left ventricle
Which of the following is the correct sequence of blood flow in birds and mammals
Vena cava → right atrium → right ventricle → pulmonary artery
Damage to the sinoatrial node in humans...
Would disrupt the rate and timing of cardiac muscle contractions
The greatest difference in concentration of respiratory gases is found in which pair of mammalian blood vessels?
The pulmonary vein and the jugular vein
If a molecule of carbon dioxide is released into the blood of the left toe, it must pass through all of the following except...
• An alveolus, the pulmonary vein, the trachea, the right atrium
pulmonary vein
The velocity of blood flow is the lowest in the capillaries because...
The total cross-sectional area of the capillaries is greater than the total cross-sectional area of the arteries or any other part of circulation
If, during protein starvation, the osmotic pressure on the venous side of capillary beds drops below the hydrostatic pressure, then
Fluids will tend to accumulate in the tissues
Large proteins such as albumin remain in the capillaries rather than diffusing out, resulting in...
Development of osmotic pressure difference across capillary walls
Voice sounds are produced by the
The primary function of the ___ are to warm, filter, and humidify air
nasal cavity
The smallest airway through which inspired air passes before gas exchange occurs in the mammalian lungs is the...
Compared with the interstitial fluid that bathes the active muscle cells, blood reaching these muscle cells in arteries has a...
higher PO2
Steps of inhalation (1-5) and exhalation (6-10)
1. Diaphragm and rib muscle contract 2. Lung volume increases 3. Air moves into the nose, down the trachea, bronchi, and bronchioles 4. Air enters alveoli 5. O2 diffuses into blood and CO2 diffuses into alveoli 6. Diaphragm and rib muscles relax 7. Lung volume decreases 8. Air moves out of alveoli 9. Air moves up bronchioles, bronchi, and trachea 10. Air leaves nose or mouth
Most carbon dioxide is carried from body tissues to the lungs
bicarbonate ions
By picking up hydrogen ions, hemoglobin prevents the blood from becoming too
In the blood, most oxygen that will be used in cellular respiration is carried from the lungs to the body tissues
combined with hemoglobin
The Bohr shift on the oxygen-hemoglobin dissociation curve is produced by changes in
Blood returning from the mammalian heart in a pulmonary vein drains first into the
left atrium
the site of nutrient and oxygen delivery to tissues
capillary beds