bio chapter 1 and 2
Which model organism is used to represent all prokaryotes?
E. coli
T/F: Sugar is not an organic molecule
False
What is NOT a reason scientists study yeast?
It lacks a nucleus so it is easy to genetically manipulate
what makes a cell living
MR GREY
Which of the following organelles is (are) surrounded by at least a double membrane? -Smooth Endoplasmic Reticulum and Rough Endoplasmic Reticulum -Mitochondria and Chloroplasts -Chloroplasts and Endoplasmic Reticulum -Ribosomes and Mitochondria -Endoplasmic Reticulum and Nucleus -Lysosomes and Golgi
Mitochondria and Chloroplasts
Which statement is NOT true of mitochondria?
Mitochondria are not present in plant cells
True or False. If False, explain why. The innermost shell of an atom can hold a maximum of two electrons
True
ER
endoplasmic reticulum (ER) is an irregular maze of interconnected spaces enclosed by a membrane
In summary, the molecular weight of an atom is given by which equation:
protons + # neutrons = molecular weight
Which of these cannot be resolved with a conventional light microscope? Cell nucleus Ribosome Bacterium Mitochondrion Embryonic cell
ribosome
ATP
(adenosine triphosphate) a main energy source that cells use for most of their work. cellular respiration consumes oxygen take out carbon
Which of the following is NOT one of the three main tenets of the Cell Theory? All life is composed of cells. All cells are derived from pre-existing cells All cells contain a nucleus Cells are the fundamental unit of life.
All cells contain a nucleus
What is an atom called when it has more electrons than protons?
Anion (-)
What do eukaryotic cells have that prokaryotes lack?
A nucleus and other internal organelles
Which of the following is a model plant used by scientists?
A. thaliana
Cells are made up of a limited number of elements, four of which—--------------------—make up about 96% of a cell's mass.
CHON
central dogma
DNA-transcription-RNA-translation-protein
cytosol
Fluid portion of cytoplasm, a host of large and small molecules, crowded together so closely that it behaves more like a water-based gel than a liquid solution
MR GREY
M- metabolize R-reproduce G-growth R-respond E- evolve Y-DNA +made of cells
amphipathic
Molecules that possess both hydrophobic and hydrophilic regions
acid
Substances that release protons when they dissolve in water
base
any molecule that accepts a proton when dissolved in water
Chloroplast
are large, green organelles that are found only in the cells of plants and algae, not in the cells of animals or fungi. These organelles have an even more complex structure than mitochondria: in addition to their two surrounding membranes, they possess internal stacks of membranes containing the green pigment c
Match the following. Protein lipids nucleotides carbohydrates
proteins: CHONS lipids: CHO carbohydrates: CH2O RATIO nucleotides: CHONP
budding yeast Saccharomyces cerevisiae
small, single-celled fungus that is at least as closely related to animals as it is to plants. reproduces almost as rapidly as a bacterium. Yet it carries out all the basic tasks that every eukaryotic cell must perform. Genetic and biochemical studies in yeast
The mass of a proton is approximately equal to the mass of, [Know - If a neutron was to break apart what would result?]
A neutron
Avogadro's number references,
All of the above examples apply to Avogadro's number: The number of atoms in a gram of substance The number of molecules in a gram of water The number of particles in a gram of substance
Many of the mechanisms that cells use for maintenance and reproduction were first studied at the molecular level in bacteria. Which bacterial species had a central role in advancing the field of molecular biology?
E. coli
Which of the following bonds do you expect to be the MOST polar? H-C H-N C-C H-F H-O
H-F
ancient bacteria are thought to have led to the existence of mitochondria and chloroplasts in eukaryotic cells. According to the endosymbiotic theory, these bacteria were transformed over time to "organelles" and:
are no longer considered separate cells and cannot exist without its host
Which of the following is an example of a polysaccharide? a Glycogen b Chitin c Starch d Cellulose e All of the above
e. all above
Homologous
genes from different organisms have very similar nucleotide sequences, it is highly probable that both descended from a common ancestral gene
Which term describes genes (and gene products) related by a common ancestral gene?
homologous
Cell Theory states: I. All living cells must have a cell wall. II. All living cells require glucose for survival. III. The basic unit of life is a cell membrane. I. only II. only III. only I and II I and III None of the above
none of the above
Endocytosis
process by which a cell takes material into the cell by infolding of the cell membrane
Which of the following is the most abundant macromolecule in a cell?
protein
True or False. Both covalent bonds and non-covalent bonds are needed to form a macromolecular assembly.
true
(Q011) There are 90 naturally occurring elements on the earth, __________ of which compose 96% of the mass of living organisms. 4 6 7 8
4
fluorescence microscopes
Instrument used to visualize a specimen that has been labeled with a fluorescent dye; samples are illuminated with a wavelength of light that excites the dye, causing it to fluoresce.
unsaturated
hydrocarbon tail contains one or more double bonds
saturated
hydrocarbon tail has no double bonds
electron microscope
microscope that forms an image by focusing beams of electrons onto a specimen
light microscope
microscope that uses a beam of light passing through one or more lenses to magnify an object
(Q017) Table 2-14 indicates the number and arrangement of electrons in the first four atomic electron shells for selected elements. On the basis of the information in the chart and what you know about atomic structure, which elements form stable but reactive diatomic gases?
nitrogen; oxygen FEEDBACK: An oxygen atom with six outer electrons needs two more to attain a stable outer shell. This can be achieved by forming two covalent bonds with a second oxygen, as shown on the right. Similarly, a nitrogen atom needs three more electrons and makes three covalent bonds with another nitrogen atom.
Consider the evolutionary tree Figure in your textbooks (page 24 - Figure 1-28) and then answer the questions. Scientists study model organisms within these groups to gain insight into these types of organisms and their genetic heritage. Which of these statements is consistent with the data presented in the evolutionary tree? -Saccharomyces cerevisiae do not contain chloroplasts. -Drosophila melanogaster do not contain mitochondria. -Caenorhabditis elegans contain chloroplasts. -All of these choices are correct regarding these organelles. -None of the above
-Saccharomyces cerevisiae do not contain chloroplasts.
(Q018) Which of the following factors DO NOT influence the length of a covalent bond? -the tendency of atoms to fill the outer electron shells -the attractive forces between negatively charged electrons and positively charged nuclei -the repulsive forces between the positively charged nuclei -the minimization of repulsive forces between the two nuclei by the cloud of shared electrons
-the tendency of atoms to fill the outer electron shells : The tendency to complete the outer electron shell is the reason covalent bonds form, but it does not address the length of the bond that is formed.
How many membranes are present around ribosomes?
0
what is the cell theory
1. cell is the basic unit of life. 2. all living things are made of cells. 3. cells come from preexisitng cells
Which of these molecules would be least expected to readily dissolve in water? acetic acid acetone potassium chloride 2-methylpropane sucrose
2-methylpropane
How many domains of life exist?
3, bacteria, archaea, eukarya 5 kingdoms(minimum): animal, plant, protista, fungi, bacteria, archaea 2 classes: prokaryotes eukaryotes
(Q044) Because there are four different monomer building blocks that can be used to assemble RNA polymers, the number of possible sequence combinations that can be created for an RNA molecule made of 100 nucleotides is
4^100.
(Q026) Larger molecules have hydrogen-bonding networks that contribute to specific, high-affinity binding. Smaller molecules such as urea can also form these networks. How many hydrogen bonds can urea (Figure 2-26) form if dissolved in water?
6
(Q005) Figure 2-5 depicts the structure of carbon. Use the information in the diagram to choose the correct atomic number and atomic weight, respectively, for an atom of carbon. 6 neutron 6 proton 6 electron
6.12
Which is NOT true of a base? A base, in solution, has a pH lower than 7. A base, in solution, is alkaline. A base is the chemical opposite of an acid. A base is any molecule capable of accepting a proton. None of the above
A base, in solution, has a pH lower than 7.
Scanning Electron Microscope (SEM)
A microscope that uses an electron beam to scan the surface of a sample, coated with metal atoms, to study details of its topography.
Which of the following are prokaryotes?
Archaea and bacteria
Arabidopsis thaliana model plant
Because genes found in Arabidopsis have counterparts in agricultural species, studying this simple weed provides insights into the development and physiology of the crop plants upon which our lives depend, as well as into the evolution
Which statement is NOT true of chloroplasts?
Chloroplasts are present in essentially all eukaryotic cells and in certain photosynthetic bacteria
(Q010) You have a concentrated stock solution of 10 M NaOH and want to use it to produce a 150 mL solution of 3 M NaOH. What volume of water and stock solutions will you measure out to make this new solution? 135 mL of water; 15 mL of NaOH stock 115 mL of water; 35 mL of NaOH stock 100 mL of water; 50 mL of NaOH stock 105 mL of water; 45 mL of NaOH stock
Correct! 105 mL of water; 45 mL of NaOH stock
(Q028) __________ play an important role in organizing lipid molecules with long hydrocarbon tails into biological membranes. Hydrogen bonds Ionic bonds Hydrophobic forces Van der Waals attractions
Correct! Hydrophobic forces
Which of the following are pyrimidines
Cytosine , Thymine Cytosine , Uracil
Which type of bond makes it possible for a macromolecule to interact with great specificity with just one out of the many thousands of different molecules present inside a cell? [Select all that apply] Covalent Ionic Hydrogen all of the above
Ionic Hydrogen
Which is not evidence for the endosymbiotic origins of mitochondria and chloroplasts? Mitochondria and chloroplasts are surrounded by a double membrane. Mitochondria and chloroplasts contain their own DNA. Mitochondria and chloroplasts resemble bacteria. Mitochondria and chloroplasts have similar DNA. Mitochondria and chloroplasts reproduce by dividing in two via binary fission.
Mitochondria and chloroplasts have similar DNA.
In studying osteoporosis in humans, you wish to test a newly designed treatment for efficacy. Your best choice for a model organism would be, [from this list], Pisum sativum. Mus musculus. Escherichia coli. Caenorhabditis elegans. Arabidopsis thaliana.
Mus musculus.
If the isotope 32-S has 16 protons and 16 neutrons, how many protons, neutrons, and electrons will the isotope 39-S have, respectively?
None of the above
Which of the following laws of physics and/or chemistry may living things violate?
None of these can be violated at all!
------------- bonds link amino acids together to form ---------------.
Peptide; proteins
Exocytosis
Process by which a cell releases large amounts of material
What was used to define the 3 domains of life? a Cell morphology b RNA similarity c Cell length d Presence and absence of a nucleus e None of the above
RNA similarity based on the different sequences
Which of the following covalent bonds is relatively nonpolar? The bond between carbon and hydrogen, C, and H The bond between nitrogen and hydrogen, N, and H The bond between oxygen and hydrogen, O, and H All of the above None of the above
The bond between carbon and hydrogen, C, and H
The correct definition of cytosol would be,
The gel-like matrix between the plasma membrane and the nuclear membrane.
When cells are viewed using a electron microscope which one of the following facts is false?
The specimen may be alive
All known living cells obey the same chemical and physical laws as nonliving things. Like all other forms of matter, they are made of ---------------, which are the smallest unit of a chemical element that retain the distinctive chemical properties of that -----------------.
atoms, element
What is NOT a reason scientists study yeast? a It is as closely related to animals as it is to plants. b It lacks a nucleus so it is easy to genetically manipulate. c It carries out all the basic tasks a eukaryotic cell must perform. d It can reproduce as rapidly as bacteria. e It can be grown in the laboratory.
b
Which of the following is not a fundamental property of carbon? Carbon-containing molecules form stereoisomers. Carbon atoms are most likely to form ionic bonds with one another. Carbon has a valence of 4. Carbon-containing molecules are stable. Carbon-containing molecules are diverse.
carbon atoms are most likely to form ionic bonds with one another.
(Q029) Substances that release protons when they dissolve in water are acids. Which of the following household substance is acidic? coffee bleach hand soap water
coffee
PH scale
concentration of H+ is expressed using a logarithmic scale
This system of protein filaments, called the --------------------, is composed of three major filament types
cytoskeleton.
Which of the following statements is false? a. During a condensation reaction, a water molecule is expelled, resulting in a bond formation between 2 molecules. b When a condensation reaction occurs between 2 monosaccharides; a covalent, glycosidic bond is formed. c During a hydrolysis reaction, a water molecule is consumed, resulting in a broken bond. d During a hydrolysis reaction of a disaccharide, a water molecule is consumed, breaking a bond that results in 2 monosaccharides. e A water molecule is expelled during both, condensation and a hydrolysis reaction.
e. A water molecule is expelled during both, a condensation and a hydrolysis reaction
(Q033) Which of the following are examples of isomers? glucose and galactose alanine and glycine adenine and guanine glycogen and cellulose
glucose and galactose FEEDBACK: Glucose and galactose are both six-carbon sugars and thus both have the formula C6H12O6. They are therefore isomers of each other. Adenine and guanine are bases containing different numbers of nitrogen and oxygen atoms. Glycogen and cellulose are different polymers of glucose. Alanine and glycine are amino acids with quite different side chains: a methyl group and a hydrogen atom, respectively.
what did light microscope allow?
identification of organelles
Look at the image. The element with the atomic number 9 is not shown. However, from this pattern what kind of molecular force would it most likely participate in?
ionic
(Q016) Table 2-14 indicates the number and arrangement of electrons in the first four atomic electron shells for selected elements. On the basis of the information in the chart and what you know about atomic structure, which elements will form ions with a net charge of +2 in solution? carbon; sulfur helium; neon sodium; potassium magnesium; calcium
magnesium; calcium
The DNA in the nucleus of eukaryotic cells is separated from the cytoplasm by the:
nuclear envelope
(Q024) Which of the following expressions accurately describes the calculation of pH? pH = -log10[H+] pH = log10[H+] pH = -log2[H+] pH = -log10[OH-]
pH = -log10[H+]
(Q041) The variety and arrangement of chemical groups on monomer subunits contribute to the conformation, reactivity, and surface of the macromolecule into which they become incorporated. What type of chemical group is circled on the nucleotide shown in Figure 2-41?
phosphoryl
Model Animals Include Flies, Fish, Worms, and Mice
small fruit fly Drosophila melanogaster Drosophila have turned out to be amazingly similar to those of humans nematode worm Caenorhabditis elegans (Figure 1-34), a harmless relative of the eelworms that attack the roots of crops. Some 70% of human genes have some counterpart in the worm, and C. elegans, like Drosophila, has proved to be a valuable model for many of the developmental processes that occur in our own bodies. zebra fish: creature is transparent for the first 2 weeks of its life, it provides an ideal system in which to observe how cells behave during development in a living animal
E. coli
small, rod-shaped cell normally lives in the gut of humans and other vertebrates, but it also grows happily and reproduces rapidly in a simple nutrient broth in a culture bottle.
(Q015) Table 2-14 indicates the number and arrangement of electrons in the first four atomic electron shells for selected elements. On the basis of the information in the chart and what you know about atomic structure, which elements will form ions with a net charge of +1 in solution? carbon; sulfur helium; neon sodium; potassium magnesium; calcium
sodium; potassium
(Q046) Macromolecules in the cell can often interact transiently as a result of noncovalent interactions. These weak interactions also produce stable, highly specific interactions between molecules. Which of the factors below is the most significant in determining whether the interaction will be transient or stable? the size of each molecule the concentration of each molecule the rate of synthesis surface complementarity between molecules
surface complementarity between molecules
Cytoskeleton
system of protein filaments, is composed of three major filament types. actin filament they are abundant in all eukaryotic cells but occur in especially large numbers inside muscle cells, where they serve as a central part of the machinery responsible for muscle contraction. The thickest filaments in the cytosol are called microtubules, because they have the form of minute hollow tubes. Intermediate in thickness between actin filaments and microtubules are the intermediate filaments, which serve to strengthen the cell. These three types of filaments, together with other proteins that attach to them, form a system of girders, ropes, and motors that gives the cell its mechanical strength, controls its shape, and drives and guides
genome
the complete instructions for making an organism, consisting of all the genetic material in that organism's chromosomes
genome
the complete instructions for making an organism, consisting of all the genetic material in that organism's chromosomes. cells express different genes
The limit of resolution can best be defined as, -the distance that two objects must be apart to be distinguished as separate objects. -the magnification power of a microscope. -the distance that an object must be moved to be distinguished from its background. -the solvent that must be available to remix a solution. -the inverse of the wavelength of light; it is greatest for black light. all of the above none of the above
the distance that two objects must be apart to be distinguished as separate objects.
Scientists were studying yeast cells in which a mutation inactivated a gene required for cell division. Without this gene—and the protein it encoded—these mutant yeast cells were unable to divide normally. But the scientists discovered that introducing a related protein from human cells could "rescue" these mutant yeast cells, allowing the cells to resume normal division. Based on this finding, the most likely conclusion is that: [How we know section] -the proteins that control cell division in yeast and humans are functionally equivalent and have been conserved, almost unchanged, for more than a billion years. -yeast cells most likely obtained their cell-division proteins from the cells of early humans. -modern humans most likely obtained their cell-division proteins from ancient yeast. -yeast cells require human proteins to divide. -yeast and humans diverged from a common ancestor much more recently than previously thought, perhaps fewer than a million years ago.
the proteins that control cell division in yeast and humans are functionally equivalent and have been conserved, almost unchanged, for more than a billion years.
(Q018) Which of the following factors DO NOT influence the length of a covalent bond? -the tendency of atoms to fill the outer electron shells -the attractive forces between negatively charged electrons and positively charged nuclei -the repulsive forces between the positively charged nuclei -the minimization of repulsive forces between the two nuclei by the cloud of shared electrons
the tendency of atoms to fill the outer electron shells FEEDBACK: The tendency to complete the outer electron shell is the reason covalent bonds form, but it does not address the length of the bond that is formed.
(Q013) An ionic bond between two atoms is formed as a result of the sharing of electrons. loss of electrons from both atoms. loss of a proton from one atom. transfer of electrons from one atom to the other.
transfer of electrons from one atom to the other.
a transmission electron microscope
type of electron microscope used to look at thin sections of tissue