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1
Q

What is a scientific hypothesis

A

c. a potential explanation of a natural phenomenon that can be tested through experimentation

2
Q

] What is the difference between a scientific hypothesis and a theory

A

A hypothesis is an idea of what the explanation is. it needs to be tested and proved. A theory is a hypothesis that has not been disproven after several years

3
Q

True or False: If an experiment provides support for a scientific hypothesis, it has now been proven

A

False

4
Q

Which of the following is NOT a characteristic of living organisms? A. heritable information encoded in DNA which allows them to function B. capable of a response to changes in the external environment C. maintenance of a constant internal environment D. composed of more than one cell.

A

D. Composed of more than one cell

5
Q

Give an example of the principle of Emergent Properties at the level of a cell.

A

Atoms joined in a chemical bond

6
Q

True or False: Deductive reasoning seeks to describe natural phenomena by proceeding from specific tests to a general conclusion

A

False. Deductive reasoning is general to specific and interdictive reasoning is specific to general

7
Q

True or False: This is a good definition of ‘science’—a way of knowing about the natural world…

A

False

8
Q

Which of the following is true of DNA? A. universal means of encoding heritable information, so forms the basis for the unity of all living organisms B. variable sequence of ‘building blocks’ forms the basis for the diversity of all living organisms C. is contained within the nucleus of eukaryotic organisms D. controls the development, growth and activity of all organisms E. all of these are true

A

e. all of these are true

9
Q

Which of the following represents the correct application of binomial nomenclature? A. Escherichia coli B. Escherichia coli C. Escherichia Coli D. escherichia coli E. Escherichia Coli F. E coli.

A

b. escherichia coli

10
Q

All prokaryotic organisms belong to Domain ______________ or Domain ________________

A

Bacteria;Archaea

11
Q

What is the difference between a ‘producer’ and a ‘consumer’?

A

A producer uses energy and raw materials to produce their own food, while consumers feed on the tissues and fluids of producers to get their food

12
Q

What is one advantage that sexually reproducing organisms may have that is not present in asexually reproducing individuals?

A

Sexually producing organisms produce an individual with traits from both the mother and the father. It is a mixture. Asexually reproducing organisms produce a clone of the parents

13
Q

Positively charged subatomic particles in the core of an atom are called ___________ and negatively charged subatomic particles orbiting the core of an atom are called ____________

A

protons; electrons

14
Q

True or False: An isotope of Nitrogen with 13 neutrons radioactively decays to Carbon

A

true

15
Q

What is meant by CHONP

A

Carbon, Hydrogen, oxygen, nitrogen, and phosphorous. Most abundant elements in body

16
Q

A molecule formed through sharing of electrons is called a ______________________bond.

A

Covalent bond

17
Q

A bond formed through the attraction of opposite charges (such as between Na+ and Cl-) is called an __________________bond.

A

Ionic bond

18
Q

True or False: Hydrogen bonding between water molecules is responsible for the emergent properties of water. (Describe how hydrogen bonding works—which atoms form these bonds?)

A

true. A hydrogen bond is a type of attractive interaction between an electronegative atom and a hydrogen atom bonded to another electronegative atom. This bond always involves a hydrogen atom. Hydrogen bonds can occur between molecules or within parts of a single molecule. A hydrogen bond tends to be stronger than van der waals forces, but weaker than covalent bonds or ionic bonds. Nitrogen, Flourine, and Oxygen can form these bonds.

19
Q

Describe one of the emergent properties of water.

A

Cohension, molecular attraction by which the particles of a body are united throughout the mass. Atoms stick together. Also, temperature moderation takes longer to heat and longer to cool

20
Q

What is meant by a hydrophilic substance? Give one example. What is meant by a hydrophobic substance? Give one example.

A

Hydrophilic substances is like salt. it dissolves in water. Hydrophobic is like oil. doesn’t like water

21
Q

Is NaCl (sodium chloride) polar? Does it dissolve in water?

A

Yes it is polar and yes it dissolve .

22
Q

True or False: If the outer energy level (shell) of an atom is not ‘full’ the atoms is unstable and tends to react with other atoms to gain or lose electrons.

A

true

23
Q

True or False: For a water molecule to be formed, covalent bonds between hydrogen atoms and between oxygen atoms must first be broken before new covalent bonds are made between two hydrogen atoms and one oxygen atom _______.

A

false

24
Q

In liquid water, some water molecules may separate into hydrogen ions and hydroxide ions. What is the charge of each of these ions? This reaction is known as __________________________________ Can these ions re-combine to form water? (yes or no)

A

Hydrogen Ions are H+ or 1+ and Hydroxide ions are OH- or -1. Known as disassociation. yes.

25
Q

Substances that release hydrogen ions in water are known as __________________ and substances that release hydroxide ions in water are known as _________________.

A

acids; bases

26
Q

What is a solute? What is a solvent ? Define concentration…why is the concentration of hydrogen ions in a solution important? A solution with an equal concentration of hydrogen ions and hydroxide ions is said to be __________________ (like pure water). A solution with a higher concentration of hydrogen ions than hydroxide ions is said to be ___________________ whereas a solution with a lower concentration of hydrogen ions than hydroxide ions is said to be ___________________.

A

Neutral; Acidic Solution; Basic Solution.
A solute is whats being dissolved. A solvent is whats doing the dissolving. Concentration is mass per unit volume, the concentration is important because it determines ph.

27
Q

True or False: Acidic substances have a pH value below 7 _________.

A

true

28
Q

Why is the pH of a solution inside of a cell (or in the extracellular fluid) important? What might happen to the structure and/or function of a protein if pH is not maintained within certain limits? What is the name of the paired weak acid/weak bases that act to take up or release hydrogen ions and prevent large changes in pH?

A

It is important to maintain homeostasis. Blood is slight basic so cells need to be slightly acidic. If ph is not maintained, it will dissolve. Name is buffer.

29
Q

What is metabolism?

A

Metabolism is the activities by which cells acquire and use energy to construct rearrange and break down organic molecules. Allows cells to live grow and reproduce. Catabolism refers to the breakdown and anabolism refers to the synthesis.

30
Q

True or False: Catabolism refers to reactions that result in the synthesis of new biomolecules and Anabolism refers to reactions that break biomolecules apart ____________.

A

False.

31
Q

Which biomolecules are polymers? Name the monomeric subunits which are the building blocks of each of these biomolecules. What is the reaction used by cells to synthesize a polymeric biomolecule? What is the reaction used by cells to break a polymeric biomolecule apart into its constituent monomers?

A

Cellulose, starch, glycogen, and chitin are polymers. Hydrogen, oxygen and carbon are the building blocks. The reaction used to synthesize polymeric biomolecules is polymerization and the reaction breakdown a polymeric bimolecular is monomerization

32
Q

If cellulose, starch, and glycogen are all polymers composed solely of the monosaccharide glucose, what accounts for their differing properties? Where are each of these polymers generally found?

A

Cellulose is a polysaccharide, found in plants, has long chains of glucose, does not dissolve in water, and is not easily broken down. Starch is polysaccharide, found in plants, , the covalent bonding between monomers makes a chain that coils into a spiral, it does not easily dissolve in water but is less stable than cellulose. Glycogen is a polysaccharide, the covalent bonding forms branch chains of glucose monomers, found in animal cells.

33
Q

True or False: An amino acid contains a basic amine functional group as well as an acidic carboxyl functional group ____________.

A

True

34
Q

What are the three parts of a nucleotide? True or False; when a nucleic acid is synthesized, each new nucleotide is joined to a growing chain by a covalent bond between its phosphate functional group and the sugar unit of the preceding nucleotide ___________.

A

True.

the three parts are a nitrogen base, a 5 carbon sugar and phosphate group.

35
Q

What does RNA stand for? Which nucleotides make up this biomolecule? What does DNA stand for? Which nucleotides make up this biomolecule?

A

RNA stands for ribonucleic acid. Adenine, Guanine, Cytosine, and Uracil make up this biomolecule. DNA stands for deoxyribonucleic acid, A, G, C, and thymine make up this biomolecule

36
Q

What does ATP stand for? True or False: ATP contains three phosphate functional groups and the high energy bonds between these groups can be used for many cell processes such as the synthesis of biomolecules.

A

Adenosine triphosphate. True. It transports energy to cells.

37
Q

ATP itself is synthesized in which organelle

A

ATP is synthesized in the mitochondria

38
Q

Apart from the relative size of the cell, what is the most important difference between prokaryotic and eukaryotic cells? Which of these cell types generally have DNA in a circular form?

A

Ribosomes are the only organelle present. It assembles polypeptides. It is 200 nanometers and smaller than eukaryotic cell. Prokaryotic cells have no nucleus whereas eukaryotic cells do. Prokaryotic cells have DNA in a circular form.

39
Q

Multiple Choice: Which of the following is true of the Cell Membrane (Plasma Membrane)? A. Present in all cells B. Composed of a phospholipid bilayer and embedded proteins C. Functions to control the entrance/exit of substance to/from the cell (and extracellular fluid) D. All of these are correct

A

d. All of these are correct

40
Q

Multiple Choice: Which of the following is true of phospholipids? A. This biomolecule consists of a polar glycerol head and three fatty acid tails. B. This biomolecule consists of a non-polar phosphate group and two fatty acid tails. C. This biomolecule has both hydrophilic and hydrophobic regions important for membrane function. D. This biomolecule is a polymer.

A

c. This biomolecule has both hydrophilic and hydrophobic regions important for membrane function.

41
Q

What is a biofilm?

A

single celled organism living in surface coating colonies constructed of polysaccharides and glycoproteins secreted by the microorganisms may include prokaryotes and eukaryotes.

42
Q

In eukaryotic cells, what is the function of the Rough Endoplasmic Reticulum (RER)? Smooth Endoplasmic Reticulum(SER)? Golgi Body? Why are vesicles important in the Endomembrane System?

A

The function of the rough ER is to modify proteins made by attached ribosomes. The smooth ER makes lipids, breaks down carbs and fats, and inactivates toxins. The golgi body body finish, sorts and ships lipids, enzymes and proteins. Vesicles are important because they carry the biomolecules between organelles or to the cell membrane

43
Q

What are the three types of protein filaments that make up the cytoskeleton? What are the protein sub-units of these filaments?

A

The three types are micro filaments, micro tubules and intermediate filaments(structure).

44
Q

] What is the function of a chloroplast? A mitochondrion? A lysosome?

A

Chloroplast construct photosynthesis. Mitochondria makes energy molecule ATP through aerobic respiration extracts energy from carbohydrates and lipids using oxygen. Also has two membranes. Liposomes digest and recycle materials

45
Q

True or False: Plant cells do not need mitochondria as they are autotrophs, able to manufacture their own food using energy from sunlight and molecules from the environment.

A

False

46
Q

What is the function of the nucleus in a eukaryotic cell? What is meant by the term ‘nuclear envelope’? and why are nuclear pores present? What is the nucleolus?

A

Nucleus keeps DNA safe. Nuclear envelope is a double membrane functioning as protective barrier surrounding the nucleus, separating contents from cytoplasm. Nuclear pores control passage of proteins and RNA molecules through the nucleus envelope. Nucleolus is an organelle in the nucleus of eukaryotic cells

47
Q

Proteins that are synthesized in the cytoplasm by _______________ ribosomes are destined to remain in the cytoplasm to carry out their function. Proteins that are synthesized in association with the RER by ___________________ ribosomes are destined to be exported from the cell or become part of the cell membrane or an organelle (transported by vesicles).

A

free; bound.

48
Q

What is the biggest cell you can think of?

A

Ostrich egg.

49
Q

What are the differences between DNA and mRNA (nucleotide monomers, pentose sugars, single or double strand, length)? What are the differences between replication and transcription (what is used as a template (RNA or DNA, the entire strand or partial)? Is the template copied one time or many? Hint: recall the ‘Christmas Tree’ …What is the enzyme that catalyzes the addition of nucleotides in a growing chain of DNA? RNA? What is the product of replication (RNA or DNA, single strand or double strand)? Transcription?

A

DNA: double stranded, pentose sugar is deoxyribose, monomers are: ATGC. RNA single stranded, pentose sugar is ribose, monomers are AUCG. DNA replication and transcription both synthesize new nucleic acid molecules by page pairing, replication involves separating the entire double strand of DNA. each strand acts as a template for a new strand of DNA. In transcription, a portion of one strand of DNA acts as a template for a new strand of mRNA that is complementary to DNA.

50
Q

Multiple Choice: Which of the following is true of mRNA in eukaryotes? A. It is transcribed in the cytoplasm for immediate translation by ribosomes B. It is transcribed and translated in the nucleus by ribosomes C. It is translated in the nucleus, modified & exported to the cytoplasm and transcribed by ribosomes D. It is transcribed in the nucleus, modified & exported to the cytoplasm and translated by ribosomes

A

D. It is transcribed in the nucleus, modified and exported to he cytoplasm and translated by ribosomes

51
Q

True or False: mRNA = messenger RNA because it transcribes the information contained in DNA in the nucleus and delivers it in a form usable to a ribosome in the cytoplasm for protein synthesis.

A

True

52
Q

Multiple Choice: Which of the following is true of the ‘Central Dogma’ of genetic information flow? A. DNA is replicated, then transcribed to RNA & translated to Protein B. DNA is translated to RNA, then replicated & transcribed to Protein C. RNA is replicated, then transcribed to Protein & translated to DNA D. Proteins are translated to DNA, then replicated & transcribed to RNA E. Central Dogma is a lot better than Peripheral Dogma

A

A. DNA is replicated, then transcribed to RNA and translated to Protein

53
Q

What is the difference between a gene and a chromosome? True or False: One gene can code for a single protein only. True or False: Each chromosome contains a single gene. True or False: Alternative Splicing allows one gene to code for more than one protein. Multiple Choice: Which of the following are true of chromosomes? A. Humans have 46 pairs of chromosomes ( 23 pairs of autosomes, 23 pairs of sex chromosomes) B. Chromosomes exist in a diffuse, thread like state that allows for replication C. Chromosomes exist in a coiled, condensed state that allows for transcription D. Quit trying to confuse me!!! None of these are correct! (If you choose this answer, what is wrong with A, B and C?)

A

False; fale; true;

c. Chromosomes exist in a coiled, condensed state that allows for transcription

54
Q

True or False: The two strands of dsDNA are identical to each other. True or False: The two strands of dsDNA are complementary to each other. True or False: If the sequence of one strand ofdsDNA is known, the sequence and orientation of the other strand can be determined. (Explain)

A

False; true; true

The sequence can be determined due to base pairing (A=t, g=c, a=u)

55
Q

During transcription, which strand of DNA (the ssDNA template) is used to synthesize mRNA? Is this strand the sense strand or the anti-sense strand? Why does it matter which strand is used as a template?

A

RNA polymerase is used to synthesize mRNA

56
Q

Multiple Choice: Which of the following is true of a codon? A. It is a triplet sequence of nucleotides present on a tRNA that specifies a protein. B. It is a triplet sequence of nucleotides present on a tRNA that specifies an amino acid. C. It is a triplet sequence of nucleotides present on an mRNA that specifies an amino acid. D. It is a triplet sequence of nucleotides present on DNA that specified mRNA

A

c. it is triplet sequence of nucleotides present on an mRNA that specifies an amino acid

57
Q

True or False: Codons are triplet sequences of nucleotides present on an mRNA and anti-codons are triplet sequences of nucleotides present on tRNA (both are specific for a certain amino acid). True or False: tRNA molecules, amino acids, and large and small RNA subunits are all present in the nucleus for protein synthesis. (If this is False, what is wrong with this statement?)

A

True. The tRNA-amino acid complexes must be made. This complex must bind to the mRNA-ribosome assembly site. The correct amino acid is assured by the matching of the anti-codon on the anti codon not the tRNA to the codon on the mRNA. A peptide bond is formed between the new amino acid and the growing polypeptide chain.

58
Q

What is the difference between an intron and an exon?

A

Introns: while they may contain information that regulates the transcription of the gene, they do not contain sequences that will be translated into the protein.
Exons: are the sequence that will remain in the mature mRNA

59
Q

Give an example of a silent mutation. Give an example of a frame-shift mutation.

A

Silent mutation: it has no effect on the gene’s product because both codon specify the same amino acid (changes a UCU codon to UCC is silent)
Frame shift mutation: certain mutations can alter the reading frame

60
Q

Photosynthesis can summarized by which simplified chemical reaction (from the power-point)? True or False: The chemical reaction for cellular respiration is the reverse of this reaction.

A

true

61
Q

.NADP+/NADPH is the electron carrier utilized in photosynthetic reactions. What is the oxidized form of this molecule? What is the reduced form of this molecule? True or False? This molecule transfers electrons and H+ from the electron transport chain(s) of the Light Reactions of Photosynthesis to the Calvin-Benson Cycle.

A

The coenyme NADP+ is the final electron acceptor, NADP+ is the oxidation form of the coenzymes, becomes reduced to NADPH.
True

62
Q

True or False: The Light Reactions of Photosynthesis occur only in the presence of sunlight (that’s why they are named the Light Reactions)! True or False: The Dark Reactions of Photosynthesis occur only in the absence of sunlight). OR True or False: The Dark Reactions of Photosynthesis are simply called that because sunlight is not directly required.

A

true; false; true

63
Q

Multiple Choice: Which of the following is true of the Light Reactions of Photosynthesis? A. These reactions are the ‘photo’ part of Photosynthesis B. Photons strike pigments in Light Harvesting Complexes and transfers the energy to a Reaction Center. C. In a Reaction Center, the energy boosts the electrons in Chlorophyll a to an electron transfer chain. D. The electron transfer chain (ETC) extracts the energy of the electrons in a step-wise process through a series of redox reactions E. All of these are true

A

E. All of these are true

64
Q

Multiple Choice: Which of the following is true of Photosystems? A. There are two—Photosystem I and Photosystem II (they work together in Non-Cyclic Photosynthesis) B. Photosystem I can work alone to produce ATP (but not NADPH or oxygen) in Cyclic Photosynthesis C. Photosystem II can work alone to produce NADPH (but not ATP or oxygen) in Cyclic Photosythesis d. Photosystem II was discovered first, so of course it is more important….

A

A. There are two- Photosystem I and Photosystem II

65
Q

True or False: The Dark Reactions of Photosynthesis are also known as the Calvin-Benson Cycle. Multiple Choice: Which of the following is true of the Dark Reactions of Photosynthesis? A. These reactions are the ‘synthesis part of Photosynthesis B. NADPH and ATP produced in the Light Reactions provide the energy to run the Dark Reactions. C. Carbon Dioxide is “fixed” by the enzyme RUBISO as part of RuBP in the Calvin-Benson Cycle. D. Glucose is produced and RuBP is regenerated in the Calvin-Benson Cycle.

A

true.
all true
Rubisco fixed becomes organic

66
Q

Multiple Choice: Which of the following is true of the Calvin-Benson Cycle? A. After Rubisco catalyzes the addition of Carbon Dioxide to RuBP, two 3-carbon PGA are formed B. Each PGA is transformed into a higher energy PGAL using ATP and NADPH C. Two PGAL (3-carbon) combine to form glucose (6 carbon) D. 6 turns of the cycle are required to synthesize one molecule of glucose (one CO2 enters/turn) E. All of these are correct.

A

E. All of these are correct

67
Q

] The light reactions occur in the ___________________ ___________________ of the chloroplast, while the dark reactions occur in the ________________________.

A

Thylakoid membrane; Stroma

68
Q

True or False: The electron transport chain pumps H+ across the thylakoid membrane. As these ions accumulate, they form a concentration gradient & travel through a protein transporter named ATP Synthase where ADP becomes phosphlorylated to ATP.
True or False: This is why plants and other autotrophs do not need mitochondria.

A

True; False

69
Q

True or False: Photosynthesis represents a strategy by which organisms obtain energy and Cellular Respiration represents a strategy by which organisms utilize energy.

A

True

70
Q

Multiple Choice: Which of the following is true of Glycolysis? A. Occurs in the mitochondria B. Requires oxygen C. Extracts all of the energy in glucose, producing 12 molecules of ATP and 6 molecules of NADH D. None of these are correct (if you pick this answer, correct A, B, and C)

A

d. None are true, it occurs in the cytoplasm of cells, can occur without oxygen, glucose is broken down into 2 molecules of pyruvic acid,yielding 2 ATP of energy.

71
Q

True or False: NADH and FADH2 are the reduced form of the electron carriers NAD+ and FAD (similar to NADP+/NADPH in Photosynthesis) True or False: Glycolysis requires an energy input in the form of 2 ATP to generate ATP, NADPH and 2 molecules of 3-carbon pyruvate from glucose.

A

True; true

72
Q

Which of the following is true of the Kreb’s Cycle? A. Pyruvate from Glycoloysis enters this cycle without modification. B. Pyruvate from Glycolysis undergoes acetyl CoA formation and then enters this cycle. C. This cycle occurs in the cytoplasm D. Carbon Dioxide is ‘fixed’ (incorporated into an organic molecule) in this cycle

A

B. Pyruvate from Glycolysis undergoes acetyl CoA formation and then enters this cycle

73
Q

True or False: If oxygen is present, pyruvate from Glycolysis (in the cytoplasm) enters the mitochondria, undergoes acetyl CoA formation and enters the Kreb’s Cycle to extract carbon dioxide and energy (in the form of ATP production and reduction of the electron carriers NAD+/NADH and FAD/FADH2

A

true

74
Q

True or False: If no oxygen is present, pyruvate from glycolysis undergoes fermentation (for the production of small amounts of ATP and the regeneration of the electron carriers)

A

true

75
Q

The electron carriers NADH and FADH2 deliver electrons to an electron transfer chain in the mitochondria. The energy from these electrons is extracted by a series of redox reactions in a step-wise manner similar to that seen in Photosynthesis. A H+ gradient is built up across the inner mitochondrial membrane and the ions flow through ATP Synthase to generate ATP from ADP (chemiosmosis or oxidative phosphoryation). What is the energy pay-out in terms of ATP formed from Glycolysis + acetyl CoA formation + Kreb’s Cycle + Oxidative Phosphorylation?

A

At the last step of ETC, oxygen accepts electrons and combines with H+, forming water. The energy harvest: the breakdown of one glucose molecule yields 36 AtP.

76
Q

ribosome enzyeme complex

A

.