AP Bio Midterm

From the below table, it is apparent that

Bond     Energy (kcal/mol)

C-C          83

C=C         146

C-O          84

C=O         170

double bonds are stronger than single bonds.

All of the following are examples of maintaining homeostasis except:

A cancerous tumor continues to grow larger and then metastasizes, spreading to new areas of the body.

A solution with a pH of 7.0 has _____ times _____ H⁺ than a solution of pH 10.

1000; more

Biodiversity in a particular ecosystem

all of the above

what are the levels of ecological study from most inclusive to least inclusive

biosphere, region, landscape, ecosystem, community, population, individual

Which term refers to the attraction of water molecules to one another?

cohesion

The periodic table gives the following information about oxygen:

8

O

15.99

A scientific article that you are reading mentions oxygen-18. How is oxygen-18 different from the typical oxygen atom described in the periodic table? Select all that apply.

Oxygen is an isotope with 2 additional neutrons

A dehydration reaction can also be called a(n) _____ reaction since it forms water.

condensation

Which of the following is a function of a steroid?

a sex hormone

what organelle converts CO2 and H2O to glucose

chloroplast

Which of the following structures is the most inclusive?

nucleus

Which of the following organelles would be present in the liver for the detoxification of drugs and alcohol?

Smooth endoplasmic reticulum

As they flow over rotten logs as a fluid sheet, slime molds appear to lack any partitioning into cell units; however, slime molds do become cellular when they change form to produce spores. Also, the surface tissue of some parasitic flatworms are a "syncytium" or layer of living material that contains many nuclei and cell organelles but lacks partitioning by cell membranes. These tissues consume food and produce wastes. Should the tissues of the slime molds or the flatworms described above be considered part of living organisms?

yes; the general concept of life-is-cellular still holds because these organisms still utilize cells sometime in their life, but this shows that cell membrane partitions can be abandoned

Two potato cubes (1 mm³ and 2 mm³) were placed in a solution of iodine. The absorption of iodine can be visualized by observing the purple color from the iodine and starch reaction. Why would the smaller (1 mm³) be completely purple in a shorter amount of time?

The surface area is larger and more iodine can be absorbed.

The surface area is larger and more iodine can be absorbed.

membrane-bound organelles

Chromatin is found in metabolically active cells, while chromosomes are found in cells that are dividing. Based on this fact, one could logically conclude

chromatin must stay uncoiled to enable ribosomes to use the information in protein synthesis

The springtail is a common small insect found in rotten logs, rich soil, and other humid places. Its cuticle is water-repellant (hydrophobic) except for a strange organ, the collophore. The collophore remains in contact with water and functions in maintaining an ion balance and in secretion of wastes. The cells in the collophore would contain high numbers of

golgi bodies

Which of the following is a characteristic of chloroplasts but not mitochondria?

only chloroplasts have a triple-membrane system

Which type of cell would contain more mitochondria?

cardiac cells

Which prokaryotic structure is correctly paired with its function?

mesosomes; pouches to increase surface area

One function of the liver is to detoxify alcohol. In this process, hydrogens are removed from alcohol and transferred to oxygen, creating hydrogen peroxide. Which organelle would be predicted to be abundant in liver cells?

peroxisome

Which organelle or structure is responsible for cellular respiration?

D : mitochondria

Which of the following examples is a specific case of active transport?

Cytoplasmic Na⁺ binds to the sodium-potassium pump, ATP is used, and Na⁺ is released to the outside.

The rate of diffusion can be increased by

temperature increase

which cell is in a hypotonic solution

cell b

which cell is in an isotonic solution

cell A

WHich cell is in a hypertonic solution

cell C

Which of the following statements explains the passage of the molecule, C₆H₁₂O₆, through the selectively permeable plasma membrane?

This molecule will not pass easily through the membrane, due to the numerous hydrophilic side chains.

The major functions of the plasma membrane include

recognition and communication between different cells and tissues.

Embedded proteins in cell membranes serve a variety of purposes. The structure and function of a protein depends on

the primary sequence of the amino acids

In the production of ATP, H⁺are pumped into the intermembrane space of the mitochondria, moving the ions from low concentration to high concentration. Energy is expended to move the H⁺ ion due to

the concentration of the molecule

Cell products are secreted from the cell through

exocytosis

Which of the following associations is correct?

plasmodesmata—between adjacent plant cells to aid in exchange of cytoplasm

The cells in the heart must act in a coordinated manner and must be capable of continuous stretching. Which of the terms below describe the type of junctions found in heart cells?

gep junctions and desmosomes

A large number of chromoplasts would likely be found in which of the following types of plant cells?

leaf or fruit tissues

Which of the following is the coenzyme that functions as an electron carrier in photosynthesis?

NADP+

Alcohol-induced cardiomyopathy is a disease where an increased consumption of alcohol contributes to a weakening of the heart muscle so that it cannot pump blood efficiently. Which of the following statements best explains the events that could lead to this disease?

modification of the action of contractile proteins, actin and myosin

Graphical interpretation: Which enzyme is found in the small intestine?

trypsin

Which form of energy is correctly associated with an example?

kinetic energy: movement of muscles

the first law of thermodynamics

Energy is not created nor destroyed, but it can change from one energy form to another.

ATP is made up of…

ADP and phosphate

An enzyme is generally named by adding _____ to the end of the name of the ______.

"-ase"; substrate

Solar energy is stored in which molecules during photosynthesis?

glucose

An egg white is protein. Which of the following will denature the egg white?

cooking the egg

The following data was obtained by a group of high school students. The students were measuring the amount of oxygen gas produced during an enzymatic reaction. Each of the trials was conducted under different conditions, but with the same amount of substrate and enzyme solutions.

Table 1: Amount of O₂ in millimoles

	10 sec	20 sec	30 sec	40 sec	50 sec	60 sec
Trial 1	1.1	2	2.9	3.7	4.5	5.3
Trial 2	1.3	2.7	4	5	6.1	7
Trial 3	0.2	0.21	0.22	0.22	0.22	0.22
Trial 4	0.5	0.7	0.9	1.1	1.3	1.5
Trial 5	1.8	3.4	3.6	7.1	7.2	7.2

Which trial had the highest reaction rate and why?

Trial 2, the amount of oxygen was not highest, but the rate was highest

The table below showsfree energy change during various reactions. What conclusion(s) could appropriately drawn from this data?

Reaction	Standard Free-Energy Change (kcal/mol)
6 CO2 + 6 H2O → Sugar + 6 O2	+686
Sugar + 6 O2 → 6 CO2 + 6 H2O	-686
ATP + H2O → ADP + P	-7.3
Maltose + 6 H2O → 2 Glucose	-4.0

photosynthesis stores free energy as chemical bonds, while the other reactions release free energy by breaking chemical bonds

The light-dependent reactions of photosynthesis

release oxygen as a by-product, and split water in the process.

The ATP and NADPH produced in the noncyclic electron pathway

will be used by the light-independent reactions to reduce CO₂.

Where does the oxygen come from that is released by plants during photosynthesis?

water taken up by the roots

Chlorophyll and other accessory pigments in plants

provide electrons that will be used to produce ATP.

How could you prove that the source of the oxygen in a carbohydrate came from CO₂ and not H₂O?

use an isotope of oxygen to trace its presence in either water or a carbohydrate

Fluorescence is the emission of light at a different wavelength than the wavelength it absorbed. Extracted chlorophyll will fluoresce, but not chlorophyll in an intact leaf. The most likely reason for this difference is that

in the chloroplast, excited electrons are transferred to electron acceptors.

Which statement is true about a photosystem?

Photosystem II contains a pigment complex that loses electrons which are then replaced by electrons from water.

Which of the following sequences most closely describes the events in the Calvin cycle?
One molecule of G3P is produced
RuBP is regenerated
6 ATP molecules are used
RuBP carboxylase fixes free CO₂
An unstable 6 carbon molecule splits into two 3 carbon molecules

4, 5, 3, 1, 2

what color are carotenoids

yellow and orange

Tropical rain forests, climate change and photosynthesis are intricately tied together. If the total amount of global tropical rain forests were reduced, which consequence would have the greatest effect on climate change?

fewer trees would be available to take up CO2 from the atmosphere

Which statements correctly differentiate CAM (crassulacean acid metabolism) plants from C4 Plants

CAM plants open their stomata and fix carbon at night

What is e

the inner mitochondria membrane

what is the first phase of cellular respiration

glycolysis

true or false: The final electron acceptor in glycolysis is oxygen and this step will occur within the matrix of the mitochondria.

false

true or false: Each molecule of NADH produced in the mitochondria provides enough energy to form two ATP molecules.

false

true or false: glycolysis occurs before fermentation

true

true or false: glycolysis is a catabolic process

true

Some bacteria are strict aerobes and others are strict anaerobes. Some bacteria, however, are facultative anaerobes and can live with or without oxygen. If given the choice of using oxygen or not, which pathway should a facultative anaerobe perform?

Use oxygen since aerobic metabolism provides more ATP per molecule of carbohydrate than anaerobic metabolism.

The preparatory reaction converts….

pyruvates into acetyl CoA and carbon dioxide.

Adult humans cannot synthesize _____ out of the _____ common amino acids.

9;20

Which process produces both NADH and FADH₂?

the citric acid cycle

During the preparatory reaction of aerobic respiration what happens to the carbon molecules?

The carbon molecules are broken down from a 3-carbon to a 2-carbon acetyl group and a 1-carbon CO₂ is released.

Why is it beneficial for pyruvate to be reduced via fermentation when oxygen is not available?

all of the choices are advantages

Aerobic cellular respiration yields about ____ of the energy of glucose in ATP molecules.

39%

True or false: The breakdown of glucose in cellular respiration is a catabolic reaction.

true

Which of the following coenzymes will accept two electrons and two hydrogen ions during the oxidation of glucose?

NADH

Which statement is correct about the input and output of carbon during glycolysis?

There is an input of 6 carbons (glucose) and an output of 6 carbons (2 pyruvates).

What is the correct summary for the energy investment vs. energy harvesting steps of glycolysis?

2 ATP are invested and 4 ATP are harvested to produce a net gain of 2 ATP.

The first reaction in the citric acid cycle binds which of the following molecules together?

acetyl CoA to a C₄ molecule.

During glycolysis _____ carbons will enter the pathway and _____ carbons will leave in the form of pyruvates.

6;6

captures CO₂ from the atmosphere and converts it to two 3-carbon sugars.

what does RuBP (rubisco) do?

In which wavelength range is the rate of photosynthesis maximized for chlorophyll a and b and carotenoids?

380-500 nm

There is a bald spot under a large leafy tree where the grass does not grow. Which of the following is the most probable explanation?

the grass does not get enough sunlight

What organisms are capable of photosynthesis?

plants, algae, and some bacteria

Which of the following is a product of hydrolysis of ATP?

ADP

Increasing substrate concentration will

result in an increased rate of reaction until there is no substrate left.

Graphical interpretation: At what pH values is enzyme shape least maintained for pepsin? For trypsin?

pepsin: about 0 and 4; trypsin about 6 and 10

Which of the following is most likely to enhance the activity of an enzyme?

2-4 degree increase in tempurature

While science is not yet able to describe the phenomenon of "thinking" in physical terms, we can be certain that it is a process involving metabolic activity in brain cells. With positron emission tomography (PET scan) it is possible to inject short-lived isotopes and image the regions of the brain that have the most active metabolism during various mental activities. For different mental functions, different regions and amounts of nerve cells become active. However,

the cellular energy expended in "thinking" must be less than the chemical bond energy supplied in food to these brain cells.

There are twelve different intermediate products produced during the production of a molecule in a cell. One can expect that there

are about twelve enzymes, at least one responsible for each step in the metabolic pathway.

Which statement describes the currently accepted theory of how an enzyme and its substrate fit together?

As the substrate binds to the enzyme, the shape of the active site changes to accommodate the reaction.

Why is ATP necessary in living systems?

It supplies energy needed for a multitude of cellular functions.

The following data was obtained by a group of high school students. The students were measuring the amount of oxygen gas produced during an enzymatic reaction. Each of the trials was conducted under different conditions, but with the same amount of substrate and enzyme solutions.

Table 1: Amount of O₂ in millimoles

	10 sec	20 sec	30 sec	40 sec	50 sec	60 sec
Trial 1	1.1	2	2.9	3.7	4.5	5.3
Trial 2	1.3	2.7	4	5	6.1	7
Trial 3	0.2	0.21	0.22	0.22	0.22	0.22
Trial 4	0.5	0.7	0.9	1.1	1.3	1.5
Trial 5	1.8	3.4	3.6	7.1	7.2	7.2

Predict the rate of the reaction if the experiment had been conducted at 100°C instead of 22°C.

The rate would have decreased to zero.

Which of the following observations could lead researchers to conclude that membrane proteins move laterally within the plasma membrane?

Human and mouse cells labeled with protein markers are fused, and the hybrid cell contains a mixing of proteins on the surface.

Many fields require heavy irrigation, and in desert areas, much of that water evaporates, leaving behind solutes. This may cause plant cells…

to plasmolysis, due to the osmosis of water to a lower water potential.

Having similar ____________ would allow tissues and organs to be transplanted easily.

major histocompatibility complex proteins

In 1917, Irving Langmuir determined that amphipathic phospholipids will form an artificial membrane on the surface of water with only the hydrophilic heads immersed. From this evidence, what deduction can be made regarding the structure of the plasma membrane?

Phosphate heads are oriented toward the exterior of the cell or toward the cytoplasm.

Freshwater protozoans react to a/an _____ environment by removing water through _____.

hypotonic; a contractile vacuole

In speculating upon the origin of early cells and the cell membrane, which of the following statements is plausible?

It would be nearly impossible to have a cell without a cell membrane.

Which is the BEST definition of active transport?

movement of a substance against its concentration gradient through the release of energy from ATP

Tay-Sachs disease often affects children by progressively destroying cells in their brains due to the accumulation of a specific type of fat. This is due to the fact that

the lysosomes do not contain the appropriate enzyme to metabolize the fat.

Which of the following organelles is found only in animal cells?

centrioles

After a protein is formed by a ribosome located on the endoplasmic reticulum, which organelle would the protein be transported to next?

the golgi apparatus

The DNA of a prokaryote is found as a coiled chromosome in the _____ and the plasmids are found in the ____.

nucleoid region, cytoplasm