WorksheetsBiology-Final
Total questions: 114
Worksheet time: 3600secs
What are the seven characteristics all organisms share?
Ability to grow, develop, and reproduce; cellular organization, ordered complexity, sensitivity, energy utilization, homeostasis, and evolutionary adaptation
Ability to reproduce, growth and development, metabolism, homeostasis, heredity, evolution, and photosynthesis
Ability to reproduce, growth and development, metabolism, homeostasis, heredity, evolution, and respiration
Ability to reproduce, growth and development, metabolism, homeostasis, heredity, evolution, and digestion
What is ordered complexity?
All organisms consist of one or more cells & all living things are both complex and ordered
All living organisms are capable of growing and reproducing, and their offspring are the same species is which of the following?
Growth, development, and reproduction
What is energy utilization?
All living organisms take in energy and use it to perform work
All living organisms interact with other living organisms and their nonliving environment in ways that influence their survival; As a consequence, organisms are able to evolve adaptations to their environments. This is an example of which of the following?
Evolutionary adaptation
What is deductive reasoning?
A type of reasoning that involves drawing conclusions based on personal beliefs
Using specific observations to construct general scientific principles
The reasoning of mathematics and philosophy that is used to test the validity of general ideas in all branches of knowledge
A method of reasoning from the particular to the general
What is inductive reasoning?
Using specific observations to construct general scientific principles
A type of reasoning that involves drawing conclusions based on what is already known
The reasoning of mathematics and philosophy that is used to test the validity of general ideas in all branches of knowledge
A type of reasoning in which general principles are inferred from specific observations
What is a hypothesis?
A suggested explanation that accounts for observations of the environment
The test of a hypothesis is an __
What is the difference between a control and experimental group?
The control group the variable of interest is kept constant (BASELINE)
In the experimental group the variable of interest is altered
Which definition does this apply to: Theory- the body of interconnected concepts that is supported by scientific reasoning and experimental evidence to explain a fact, provides framework
Theory definition 1
Theory definition 2
What is natural selection?
the differential reproduction of genotypes; caused by factors of the environment that leads to a evolutionary change
Biologists agree that all organisms alive today on Earth descended from a simple cellular organism that arose about 3.5 billion years ago Some of the characteristics of that organism have been preserved throughout evolutionary history; How is DNA/ genetic code proof of this?
The storage of hereditary information in DNA is common to all living organisms
What are valence electrons?
The electrons in the outermost energy level of the different elements
What characteristic of an element reflects how many of the eight valence positions are filled?
Chemical behavior
What 4 elements make up 96.3% of the weight of our bodies?
What is electronegativity?
A property of atomic nuclei that refers to the affinity of the nuclei for valence electrons
The hydrogen bonding of water means that water molecules are attracted to one another, water is cohesive. What is water's cohesion responsible for? (select all that apply)
For it being a liquid, not a gas, at moderate temperatures
Surface tension, the water molecules on the surface of the water are hydrogen-bonded to the molecules below them
Any substance that dissociates in water to increase the [H+] and lower the pH is a_
Acid
Base
A substance that combines with H+ when dissolved in water, and thus lowers the [H+] is a _
Acid
Base
What are polymers?
A long molecule built by linking together a large number of small, similar chemical subunits called monomers
What are the monomers is a polymer composed of?
Carbohydrate monomers (simple sugars)
Nucleic acid monomers (nucleotides)
Protein monomers (amino acids)
A simple sugar that cannot be decomposed into smaller sugar molecules is a_
What are polysaccharides?
longer sugar polymers that are made up of monosaccharides that have been joined together through dehydration reactions
What is starch?
A storage polysaccharide that consists entirely of ɑ-glucose molecules linked in long chains
A single unit of nucleic acid, composed of a phosphate group (-PO4 -), a 5-carbon sugar (ribose or deoxyribose), and a purine or pyrimidine is a _
Proteins are polymers of amino acids, what is the difference between the two?
Proteins are linear polymers made with 20 different amino acids; Amino acids the subunit structure from which proteins are produced
The loss of the native configuration of a protein or nucleic acid as a result of excessive heat, extremes of pH, chemical modification, or changes in solvent ionic interactions. What is this process called?
What is the structure of a phospholipid?
polar, hydrophilic head ;
nonpolar, hydrophobic tail
What are the THREE principles of the cell theory? (select all that apply)
All organisms are composed of one or more cells, and the life processes of metabolism and heredity occur within these cells
Cells arise only by division of a previously existing cell
Cells are the smallest living things, the basic units of organization and of all organisms
How is DNA organization different in prokaryotic cells than eukaryotic cells?
In prokaryotes, the genetic material consists of a single circular molecule of DNA; In eukaryotic cells DNA is organized into linear chromosomes that is contained within the nucleus
What is the plasma membrane?
The structure that encloses a cell and separates its contents from its surrounding environment
How is the phospholipid bilayer oriented?
The nonpolar tails of the phospholipids are together and the polar heads are to the outside
The hydrophobic heads facing outward and hydrophilic tails facing inward
What is the cytoskeleton?
An internal protein structure that provides stability and shape for the cell
True or False: In eukaryotic cells, the DNA is divided into multiple linear chromosomes
True
False
What is the smooth ER?
A portion of the ER that contains many embedded enzymes that function in the synthesis of carbohydrates and lipids
What is the function of mitochondria ?
Supports electron transport and chemiosmotic synthesis of ATP
What does the chloroplast do?
Chloroplast is responsible for
carries out photosynthesis.
closed compartments of stacked membranes called __
Grana
the matrix that surrounds the grana/thylakoid is called the __
What are the three types of cytoskeleton fibers eukaryotic cells contain?
Actin filaments, sometimes called microfilaments, Intermediate filaments, & Microtubules
What is the cytoskeleton responsible for?
The cell’s shape and movement
What is the purpose of the cell wall?
To protect and support the cell
What is passive transport?
Whenever a substance moves in and out of a cell without a cell having to expend energy
What is diffusion?
The movement of molecules and ions dissolved in water to cause a net movement of these substances across a membrane from regions of high concentration to regions of low concentration
What is facilitated diffusion?
when a molecule moves through a cell via diffusion, but through a specific channel or carrier protein, moves from a high to a low concentration
What are ion channels?
A protein that has a “hydrated” interior for ions to pass through in either direction depending on the concentration gradient
What is osmosis?
The net diffusion of water across a membrane towards a higher solute concentration
What is the difference between hypertonic and hypotonic?
Hypertonic- the solution with a higher osmotic concentration, Water diffuses out of the cell; Hypotonic - the solution with a lower osmotic concentration, Water diffuses into the cell
What is the difference between endocytosis and exocytosis?
Endocytosis is the movement of molecules into the cell, and Exocytosis is the movement of molecules out of the cell
The amount of energy actually available to break and subsequently form chemical bonds is called the __ __ of that molecule
free energy
What is significant between ΔG = + and ΔG = - ? (select all that apply)
ΔG = - , spontaneous reactions, energy of the products is less than energy of the reactants, exergonic reaction
ΔG = + , not spontaneous reactions, energy of the products is greater than energy of the reactants, endergonic reaction
What is the difference between catalysis and catalyst?
Catalysis is influencing chemical bonds in a way that lowers the activation energy needed to initiate a reaction, while Catalyst is molecules or substances that perform catalysis
What are enzymes sensitive too?
inhibitors and activators
PH levels
Temperature
enzyme cofactors
At the end of this process, the electrons have lost a lot of their energy so they are transferred to a final electron acceptor. Which of the following are the possible acceptors? (select all that apply)
If this acceptor is oxygen, this is called aerobic respiration
(forms H2O)
If this acceptor is an inorganic molecule, this is called anaerobic respiration
If this acceptor is an organic molecule, this is called fermentation
If this acceptor is an hydrogen, this is called photosynthesis
ATP is synthesized by the enzyme ATP synthase, using energy from a proton (H +) gradient. ATP synthase uses the energy from the proton gradient to catalyze the, what is the equation for this reaction?
ADP + Pi → ATP
___ is the first step of cellular respiration and it occurs in the ___ of the cell
Each glucose molecule is split into 2 G3P molecules. What is the result?
Net yield of 2 ATP
2 molecule of NADH
2 pyruvate molecules
True or false: The predicted yield for eukaryotic cells is 30 ATP and 32 ATP in bacteria
True
False
In the absence of oxygen, cells that cannot use a different electron acceptor (than O2 ), have to rely on glycolysis alone to produce ATP. Cells then have to perform fermentation instead, the electrons are then generated by __?
glycolysis
Reactions that use light energy from the sun to make ATP and reduce NAD+ (the electron carrier) to NADPH. Also oxidizes water to provide electrons and produce O2 , Light-dependent reactions.
This is which reaction of photosynthesis?
Photosynthesis reaction 1
photosynthesis reaction 2
Reactions that use the ATP and NADPH, produced by the first reaction, to power the synthesis of organic molecules from CO2 , Called carbon fixation reactions (Light-independent reactions)
What photosynthesis reaction is this?
Photosynthesis reaction 1
Photosynthesis reaction 2
What is the chemical reaction for photosynthesis?
6CO2 + 12H2O + light energy → C6H12O6 + 6H2O + 6O2
What is the stroma?
A semi-liquid substance that contains the enzymes needed to convert CO
2 into organic
molecules using ATP and
NADPH.
The energy of a photon is inversely proportional to the wavelength of the light. What does shorter or longer wavelength mean?
Photosystem II acts first, what occurs during this?
The high-energy electrons generated by the splitting of water
What is ATP synthase?
An enzyme that is embedded in the thylakoid membrane, forms, a channel that allows protons to flow in and out of the stroma
What are the four complexes responsible for light-dependent reactions present in the thylakoid membrane?
Photosystem l, Photosystem II, Cytochrome b6f complex, and ATP synthase
What is the Calvin cycle?
The cycle of reactions that allow carbon fixation
What is binary fission?
Asexual
reproduction by division of one cell
or body into two equal or nearly
equal parts
What occurs during the g1 and g2 phases of active growth?
Proteins are being synthesized
and cell organelles are being
produced
Attaches to the chromosomes and will
eventually pull the sister chromatids apart, While the spindle apparatus is forming, the nuclear envelope breaks down, At this point in prophase, the spindle apparatus extends completely across the cell from one pole to the other. What phase of mitosis is this?
What occurs during prometaphase? (select all that apply)
A second set of microtubules grows from the poles of the cell towards the center. They attach to the kinetochores present on each sister chromatid
The new microtubules begin pulling the chromosomes apart, creating enough tension to align the chromosomes at the equator of the cell
What is metaphase?
The stage in cell division where the cell membrane breaks down
The third stage of mitosis where the chromosomes are aligned at the center of the cell
The stage in cell division where the chromosomes move to opposite ends of the cell
The stage in cell division where the cell prepares for DNA replication
What is anaphase?
The shortest phase of mitosis, occurs when the cohesion proteins present on the sister chromatids are removed and the chromosomes are pulled apart
What occurs during telophase? (select all that apply)
The chromosomes begin to uncoil, closer to chromatin, so that they will be accessible for gene expression
The spindle apparatus is
disassembled
A nuclear envelope is created around the sister
chromatids at each pole
What occurs during cytokinesis?
The phase of the cell cycle when the cell
actually divides in two, involves the cleavage of the cell in
roughly equal halves
What are the two irreversible steps of the cell cycle?
DNA replication and Separation of the sister chromatids
If cells are deprived of certain growth factors, they will not make it past the G1 /S checkpoint of the cell cycle. What follows this process?
This arrests their growth and division, putting them into a dormant phase
called the G0 phase
The chromosomes begin to uncoil, closer to chromatin, so
that they will be accessible for gene expression
The new microtubules begin pulling the chromosomes
apart, creating enough tension to align the
chromosomes at the equator of the cell
the spindle apparatus
extends completely across the cell from one pole to
the other
What are gametes?
Reproductive cells (sperm and egg) (haploid); each cell contains 2 chromosomes
What are somatic cells?
All non reproductive cells, diploid (2n)
The diploid (2n) cell resulting from the fusion of male and female gametes, contains two copies of each chromosome, produced through fertilization is called _
Early in development, specific cells are set aside to undergo meiosis to form the gametes that can be used later in life to reproduce. What are these specific cells called?
Germ- line cells
___ , also called crossing over, the exchange of corresponding chromatid segments between homologous chromosomes; responsible for genetic recombination between homologous chromosomes
Recombination
The sites of recombination or crossing over are called chiasmata.
What is the chiasmata?
An X-shaped figure that shows evidence of crossing over, where two chromatids have exchanged parts
What is the role of the kinetochores of the sister chromatids ?
To provide energy for cell division
To act as a unit to capture the polar microtubules
To regulate gene expression
What are dominant traits?
An allele that is expressed when present in either the heterozygous or the homozygous condition
What is a recessive trait?
An allele that is expressed only when present in the homozygous condition, but is “hidden” by the expression of a dominant allele in the heterozygous condition.
What is genotype?
Genotype is the total set of alleles that an individual contains, the genetic constitution underlying a single trait or set of traits.
What is phenotype?
The physical appearance or other observable characteristics of that individual that result from an allele’s expression, the realized expression of the genotype
What is a dihybrid cross?
A single genetic cross involving two different traits, such as flower color and plant height
What is incomplete dominance?
Two or more alleles of a gene do not display clear dominance, the phenotype of a heterozygote is intermediate between the homozygous forms.
What are codominant alleles?
Two or more alleles of a gene are each dominant to other alleles but not to each other. The phenotype of a heterozygote for codominance exhibits characteristics of each of the homozygous forms.
What is the human ABO blood group system?
The gene that determines ABO blood types encodes an enzyme that adds sugar molecules to proteins on the surface of red blood cells that act as recognition markers for the immune system
What are the three components of a nucleic acid?
5-carbon sugar (ribose or deoxyribose), phosphate group (PO4 -), and a nitrogen-containing base
What is the phosphodiester backbone
One single strand of DNA, repeating sugar and phosphate units joined by phosphodiester bonds
Notice that each base-pair combines a two-ringed purine with a single-ringed pyrimidine. What do we call this pattern?
Opposite
Contradictory
Complementary
Unrelated
Antiparallel configuration - two DNA strands that are put together with opposite polarities (5’ > 3’ and 3’ > 5’). What is this a configuration of?
Native double-stranded DNA
What is DNA polymerase?
A class of enzymes that all synthesize DNA from a preexisting template
The main replication enzyme, responsible for the bulk of DNA synthesis is called _
DNA polymerase III
What is topoisomerase?
Any of a class of enzymes that can change the topological state of DNA to relieve torsion caused by unwinding.
DNA polymerase can also only add nucleotides in the 5’-3’ direction. ○ The combination of these two factors means that polymerases present on each DNA strand must be acting in __ directions.
What is the difference between the leading and lagging strand?
Leading strand- the DNA strand that can be synthesized continuously from the origin of replication ;
Lagging strand - the DNA strand that must be synthesized discontinuously
What occurs in leading strand synthesis? (select all that apply)
DNA primase adds a single RNA primer to the DNA strand ;
This is the ONLY priming event that occurs
DNA polymerase III then travels along the single DNA strand to add nucleotides to it;
There is nothing to stop this action except running out of DNA to synthesize
What occurs in lagging strand synthesis? (select all that apply)
1. DNA primase adds an RNA primer to the DNA strand; This must be done for EACH Okazaki fragment
2. Okazaki fragments are synthesized by DNA polymerase III
3. The RNA primer is removed by DNA polymerase I and replaced with DNA
4. DNA ligase then joins the Okazaki fragments together
5. This process is repeated until the entire DNA strand is replicated.
The __ __describes information flow in cells as DNA to RNA to protein
What is the difference between transcription and translation?
Transcription is the enzyme catalyzed assembly of a RNA molecule complementary to a strand of DNA.; Translation is the assembly of a protein on the ribosomes, using mRNA to specify the order of amino acids.
True or false: Transcription is the DNA is directed synthesis of RNA by the enzyme RNA polymerase.
This process uses complementarity, taking advantage of the complimentary bases and using DNA as a template to make RNA
True
False
What is the difference between the coding strand and the template strand?
The coding strand is the strand of a DNA duplex that is the same as the RNA encoded by a gene, has thymine instead of uracil in RNA ,while the template strand is the strand of DNA that is used as a template for RNA.
The AUG triplet, which indicates the site of the beginning of mRNA translation; this codon also codes for the amino acid methionine. This is known as the __ __
Eukaryotes have three distinct RNA polymerases, all with different cellular roles why bacteria/prokaryotes have a single RNA polymerase. What occurs during this RNA transcription? (select all that apply)
RNA polymerase I - transcribes rRNA
RNA polymerase II - transcribes mRNA
RNA polymerase III - transcribes tRNA
mRNA in eukaryotes is not the same as a primary transcript (simple copy) of a DNA strand. Which of the following is true about the transcription modifications? (select all that apply)
Modified 5’ end
Modified 3’ end produced by a different enzyme
Removal of introns (noncoding sequences)
What is pre-mRNA splicing?
In eukaryotes, the process by which introns are removed from the primary transcript to produce mature mRNA
The three-nucleotide sequence at the end of a transfer RNA molecule that is complementary to, and base-pairs with, an amino-acid–specifying codon in mRNA is known as which of the following?
anticodon loop
