Fun Science Questions! Flashcards
If the mitral valve is damaged, which of the following problems may occur?
a. backflow of blood into the L. atrium
b. backflow of blood into the R. atrium
c. Incomplete emptying of the R. ventricle
d. Incomplete emptying of the L. ventricle
A. The mitral valve is on the L side of the heart, separating the ventricle & atrium. If it prolapsed, the blood would back up into the L atrium.
T or F
Blood that passes through the tricuspid valve enters the L ventricle
False. Blood that passes through the tricuspid valve enters the R ventricle
T or F
Blood that passes through the mitral valve enters the pulmonary artery
False. Blood that passes through the mitral valve enters the L ventricle
T or F
After contraction of the L ventricle, blood enters the aorta
True
T or F
After contraction of the R ventricle, blood enters the pulmonary artery
True
T or F
After contraction of the R atrium, blood enters the R ventricle
True
T or F
The pulmonary valve ensures the blood stays in the aorta
False. The pulmonary valve ensures that blood stays in the pulmonary artery
The respiratory system supplies the body with __________ & removes __________
O2; CO2
It is through the walls of the __________ that O2 & CO2 move in & out of the capillaries in the lungs
alveoli
Which of the following happens during inspiration?
a. CO2 enters the lungs from the arterioles around the alveoli
b. O2 leaves the lungs through the arterioles around the alveoli
c. the diaphragm contracts
d. the diaphragm relaxes
C. when the diaphragm contracts, the chest cavity enlarges, creating negative pressure in the chest cavity & pulling air into the lungs.
T or F
The nervous system directs bodily defenses against external stimuli
true
T or F
The nervous system regulates heart & breathing rates
true
T or F
The nervous system supplies the body with O2 & removes CO2
False. This is a function of the respiratory system
T or F
The nervous system releases heat built up by the muscular system
False. This is a function of the integumentary system
The digestion of carbohydrates begins in the _________
mouth
The propulsion of food through the GI tract is called
a. chemotaxis
b. digestion
c. peristalsis
d. metabolism
C. Peristalsis is the rhythmic contractions that occur in the stomach & intestines, which moves food from the stomach toward the anus
The surface area for absorption in the small intestine is increased as a result of
a. enzymatic action on nutrients
b. villi & microvilli
c. mechanical breakdown that occurs during chewing
d. the parasympathetic nervous system
B. Villi & microvilli are finger-like projections of tissue in the intestines that significantly increase the surface area from which nutrients are absorbed
What kind of immunity is produced by a vaccine?
a. naturally acquired passive immunity
b. artificially acquired passive immunity
c. naturally acquired active immunity
d. artificially acquired active immunity
D. Vaccines provide an artificial source (as compared to a natural source that comes from actually having a disease) of active immunity that stimulates antibody & memory cell production
which of the following are released by damaged cells in an effort to draw WBCs to the area of damage?
a. phagocytes
b. cytokines
c. interferons
d. leukocytes
B. damaged tissue releases cytokines, which attract WBCs to the area of infection
What is the physiological benefit of a mild to moderate fever?
a. warns individual that body is under attack by a pathogen
b. stimulates release of macrophages
c. decreases metabolism
d. enhances destruction of pathogens
D. The warm body temp. that occurs during a fever accelerates the destruction of pathogens & increases the activity of WBCs
Fertility rates are higher in which of the following types of countries?
a. less developed
b. more developed
c. countries in equatorial geographic locations
d. countries in temperate geographical locations
A. fertility rates are higher in less-developed countries due to higher infant & child mortality rates
Which of the following are factors that may affect birth rates? (select all that apply)
a. religion
b. culture
c. economy
d. taxes
e. government
f. transportation
g. literacy
h. infant mortality rates
i. abortions
j. accessibility of family planning
A, B, C, E, G, H, I, J
taxes and transportation do not have a direct relationship to birth rates
2 strains of yeast are placed in a hot environment. Strain A has a mutation in a gene that results in an ability to tolerate and grow at the high temp. Strain B does not have a mutation in the same gene & is unable to survive as well in the hot environment. The yeast strains are allowed to grow & reproduce for a time. After a # of generations, a sample is tested & only strain A is found. This is an example of what?
Natural selection
T or F
The action of natural selection is due to the presence of mutations in DNA that are passed on from generation to generation
True
T or F
RNA is the messenger between DNA & protein production
True
Indicate whether the following bases are found in DNA only, RNA only, or both DNA & RNA
a. Adenine
b. Cytosine
c. Guanine
d. Thymine
e. Uracil
a. Both
b. Both
c. Both
d. DNA only; DNA contains adenine, cytosine, guanine, & thymine bases
e. RNA only; RNA contains adenine, cytosine, guanine, & uracil bases
T or F
The nucleus is the site of ATP production in cells
False. the mitochondria is the site of ATP production in cells
A scientist wishes to construct a synthetic cell & wants to make sure it has the proper organelles for protein production, transport, & secretion. Given this situation, identify whether the following statements are T or F
a. chloroplasts are needed
b. a golgi apparatus is needed
c. ribosomes are needed
a. False. Chloroplasts are involved in photosynthesis & the production of glucose in plants
b. True
c. True
Which of the following is present in both eukaryotic & prokaryotic cells? A. golgi apparatus b. endoplasmic reticulum c. mitochondrion d. cytoplasm
D. cytoplasm is contained in both types of cells
In prokaryotic (bacterial) cells, the DNA is located in the __________, & in eukaryotic (animal/plant) cells, the DNA is found in the __________.
nucleoid; nucleus
In bacteria, which lack nuclei, the large-massed nucleoids are found in the cytoplasm. In animals & plants, the nucleus separates the cytoplasm from the DNA
__________ are large structures of DNA that contain the __________, the blueprints for making an individual
chromosomes; genes
Each chromosome is a single molecule of DNA. Certain areas along this single molecule are transcribed into RNA. This makes them genes.
The central dogma of biology states that __________ gives rises to RNA, which gives rise to protein.
DNA.
DNA found in the cell nucleus, holds the code for protein production; however, it requires the messenger RNA to carry that code out of the nucleus to the ribosomes to complete protein production
T or F
Cellular differentiation may occur in a developing embryo or in an adult
True
What is an embryo?
An embryo is an animal or a plant in the early stages of development after fertilization
T or F
There are 3 steps of the cell cycle during interphase
True
Explain briefly how the DNA double helix can be released to allow replication
Enzymes initiate the process of unwinding DNA & releasing the 2 complementary strands of the DNA so DNA polymerase enzymes can duplicate them
During meiosis, a __________ cell will give rise to 4 _________ cells.
diploid; haploid
T or F
Mitosis & meiosis occur in all types of cells
False.
Mitosis occurs to replace old cells in all cell types, while meiosis occurs in gametes to bring about genetic variation amongst offspring
A new type of algae has been discovered. To determine whether or not this algae in an autotroph, the scientists should observe for which of the following?
a. chloroplasts
b. mitochondria
c. glucose
d. ATP
A.
Chloroplasts allow an autotroph to use sunlight to produce glucose. Mitochondria are found in heterotrophs. Glucose & ATP are products found in both autotrophs & heterotrophs
The organelle in plants that allows photosynthesis to occur is the _________, which contains the chemical _________ to trap energy from the sun
Chloroplast; chlorophyll
Chromosomes contain stretches of DNA called _________, which contain the information that controls particular traits for an individual
genes
These parts of the chromosome are compromised of DNA & contain information for particular traits
T or F
Genetic traits are expressed through the actions of proteins.
True
Name the major enzyme responsible for DNA replication in cells
DNA polymerase
T or F
DNA in gametes is the DNA passed on to future generations
True
__________ are the entire set of genes in organisms, while __________ are the characteristics & traits that are expressed by those genes
Genotypes; Phenotypes
genes comprise of the genotype of an individual , & the phenotype is what can be seen or observed
Different coat colors between cat breeds are examples of genotype or of phenotype?
Phenotype
Coat color is what is seen or what is expressed by the cat, which is controlled by the genotype in the cat’s DNA.
Order the following forms of electromagnetic radiation from short to long wavelengths: Infrared, X-ray, Radio, & Ultraviolet
X-ray, Ultraviolet, Infrared, Radio
Order the 7 visible forms of electromagnetic radiation from short to long wavelengths
Violet, Indigo, blue, green, yellow, orange, red
Suppose a 5-kilogram object is held at a height of 6 m. What is the object’s potential energy at the height?
300 Joules
Since potential energy is calculated by the expression PE = Mgh, it can be determined from the given information that PE = (5kg)(10meters/second²)(6meters) = 300 Joules. The appropriate units are Joules, which match kilograms & meters.
Suppose an object possess a total energy of 100 J when held at a height of 10 m. If the object is then released, how much kinetic energy & potential energy will the object have at a height of 2 m?
KE = 80 Joules
PE = 20 Joules
Conservation of energy means that the sum of the KE plus the PE equals the total energy. Since the object has fallen 1/5 of the way, the PE must be 1/5 of the total energy. (There is no KE at the 10 meters height because it has no velocity there). If the PE equals 20 Joules, then the remaining energy of 80 Joules must be in the form of KE.
Describe the construction of an atom
An atom contains a nucleus which protons and neutrons reside. Electrons circle the nucleus in varying energy levels
26
Fe
Iron
55.845
What is the atomic number?
What is the atomic mass
How many protons?
How many neutrons?
Iron has an atomic # of 26 (indicated above the Fe)
Iron AMU is 55.845
Iron has 26 protons, because that’s the atomic #
Approximately 30 neutrons because 56-26=30
How many protons would a positively charged isotope ion of O-18 have?
8
The # of protons depends only on the atomic # & is independent of the ionic charge & the isotope type. Since Oxygen has an atomic # of 8, it has 8 protons.
How many protons would a negatively charged isotope ion of C-14 have?
6
The # of protons depends only on the atomic # & is independent of the ionic charge & the isotope type. Since Carbon has an atomic # of 6, it has 6 protons.
Given reactants (X & Y), a catalyst (C), & a product (Z), order the following steps in the general catalytic reaction process
- XYC –> CZ
- CZ –> C + Z
- X + C –> XC
- Y +XC –> XYC
- X + C –> XC
- Y + XC –> XYC
- XYC –> CZ
- CZ –> C + Z
The catalyst acts on the raw reactants (X & Y) to create the 4 step product reaction chain, finally resulting in the product (Z) & catalyst (C). Notice the catalyst is available to begin the reaction again
How does a catalyst increase the rate of a chemical reaction?
By lowering the activation energy.
Reaction rates are increased when the activation energy decreases
Within a given family on the periodic table, atomic radii __________ while electronegativity __________
increase; decreases
The # of filled shells increases from top to bottom within a family, so the size of the atoms increase. Also, the greater atomic radius decreases the electronegativity, because the attraction for an electron due to the nucleus is lessened.
Which groups on the periodic table contain the most metalloids?
14, 15, 16
The metalloids are located next to the stairstep line on the periodic table. This line serves as a boundary that distinguishes metals from nonmetals.
A student has 2 material samples. One is metal (A), and the other is a nonmetal (B). The student is trying to determine which one is the metal. Which of the following could the student observe? (select all that apply)
- samples A & B both conduct an electric current
- Sample A cools rapidly when refrigerated, but sample B does not.
- Sample B heats very slowly when heat is applied, but sample A heats very quickly.
all are correct
Metals are excellent conductors of electricity; nonmetals are not. metals also cool & heat faster than nonmetals. Although, many nonmetals do not conduct electricity, some do conduct electricity, such as water.
T or F
Enzymes participate in a limited # of chemical reactions throughout the human body
False
Although enzymes are selective in their form & function, thousands of such reactions are known to occur throughout the body
T or F
Enzymes act to lower the activation energy of chemical reactions
True
T or F
An enzyme can reshape itself when placed in contact with a substrate
True
T or F
The amino-acid structure of an enzyme is important to its function
True
Why does hydrogen gas exist as H2 & never just H? (That is, why do 2 hydrogen atoms need to be connected together in the natural state?)
Hydrogen only exists in pairs because the atom is unstable on its own. A covalent bond is necessary to make the atom stable
Regarding the Lewis structure for sulfur (S), how many unshared pairs of electrons will sulfur have?
2
Since sulfur belongs to the same family as oxygen, sulfur will have the same Lewis dot structure. Since there are 6 valence electrons (and since electrons form pairs), there will be 2 unshared pairs
Balance the following reaction
__Ca(OH)2 + __ HCl –> __H2O + __ CaCl2
Ca(OH)2 + 2HCI –> 2H2O +CaCI2
The tally for the reactant (left) of the unbalanced reaction is: 1 Ca, 1 O, 2 H, & 2 Cl. Only Ca is balanced, so begin with the easiest fix, which is Cl. Place a 2 in front of HCl.
Because the right side has less H & O, a 2 needs to be placed in front of H2O
T or F
pH neutralization is an important oxidation-reduction reaction
False.
pH neutralization is an important acid-base reaction
T or F
Metabolism is an important oxidation-reduction reaction
True
T or F
Combustion is an important acid-base reaction
False.
Combustion is an important oxidation-reduction reaction
T or F
Photosynthesis is an important acid-base reaction
False.
Photosynthesis is an important oxidation-reduction reaction
T or F
Water serves as the standard for pH and has a value of 6
g
T or F
g
