BSC 108 NIDTERM EXAMS ANSWERS AND
QUESTIONS SET A+
✔✔TRUE OR FALSE: After DNA replicates before meiosis I during the S phase of
interphase, it replicates again before meiosis II - ✔✔FALSE
✔✔Meiosis I separates what? - ✔✔Homologous chromosomes
✔✔Meiosis II separates what? - ✔✔Sister chromatids
✔✔What distinguishes meiosis I from mitosis? - ✔✔Synapses and crossing over
Tetrads at the spindle equator in metaphase
Separation of homologues
✔✔What are the 3 origins of genetic variation among offspring? - ✔✔Independent
assortment of chromosomes
Crossing over
Random fertilization
✔✔Genetic variation is an advantage of what? - ✔✔Sexual reproduction
✔✔What are the 3 generations that Mendel studied? - ✔✔P generation
F1 generation
F2 generation
✔✔Mendel saw a 3:1 ratio of tall and short plants in what generation of his testcross? -
✔✔F2
✔✔What are the 4 concepts that make up Mendel's model? - ✔✔1. Alternative versions
of genes (now called alleles) account for variation in inherited characteristics
2. For each trait, an organism inherits two alleles, one from each parent
3. If the two alleles differ, then one (the dominant allele) determines the organism's
appearance and the other allele (the recessive allele) has no noticeable effect
, 4. The law of segregation: that the two alleles for a heritable character separate
(segregate) during gamete formation and end up in different gametes
✔✔What is the law of independent assortment? - ✔✔Each pair of alleles segregates
independently of other pairs of alleles during gamete formation
✔✔Most genes exist in populations in _____. - ✔✔More than two allelic forms (multiple
alleles)
✔✔In incomplete dominance, offspring can have what? - ✔✔An appearance in between
the phenotype of the two parents
✔✔In codominance, offspring can display what? - ✔✔Two dominant phenotypes at the
same time
✔✔TRUE OR FALSE: The Calvin cycle is light dependent. - ✔✔FALSE
✔✔How do light reactions use the energy of sunlight to make the energy-storing
compounds ATP and NADPH? - ✔✔1. Photons excited electrons in the chlorophyll on
the first photosystem. These photons are trapped by the primary electron acceptor. This
photosystem then replaces the lost electrons by extracting new ones from water. This is
the step that releases O2 during photosynthesis.
2. Energized electrons from the first photosystem pass down an electron transport chain
to the second photosystem. The chloroplast uses the energy released by this electron
"fall" to make ATP
3. The second photosystem transfers its light-excited electrons to NADP+, reducing it to
NADPH.
✔✔During the Calvin cycle within the stoma of the chloroplast, CO2 from the air and
ATP and NADPH produced during the light reactions are used to produce ____, which
can be used to make ____ and _____. - ✔✔G3P, an energy-rich sugar molecule
Glucose
Other organic molecules
✔✔How is C4 photosynthesis different from C3 photosynthesis? - ✔✔C4 plants close
their stomata to save water during hot and dry weather
C3 is traditional
✔✔What is the difference between aerobic and anaerobic respiration? - ✔✔Aerobic
requires oxygen
✔✔The molecules of electron transport chains are built into where? - ✔✔The inner
membranes of mitochondria
QUESTIONS SET A+
✔✔TRUE OR FALSE: After DNA replicates before meiosis I during the S phase of
interphase, it replicates again before meiosis II - ✔✔FALSE
✔✔Meiosis I separates what? - ✔✔Homologous chromosomes
✔✔Meiosis II separates what? - ✔✔Sister chromatids
✔✔What distinguishes meiosis I from mitosis? - ✔✔Synapses and crossing over
Tetrads at the spindle equator in metaphase
Separation of homologues
✔✔What are the 3 origins of genetic variation among offspring? - ✔✔Independent
assortment of chromosomes
Crossing over
Random fertilization
✔✔Genetic variation is an advantage of what? - ✔✔Sexual reproduction
✔✔What are the 3 generations that Mendel studied? - ✔✔P generation
F1 generation
F2 generation
✔✔Mendel saw a 3:1 ratio of tall and short plants in what generation of his testcross? -
✔✔F2
✔✔What are the 4 concepts that make up Mendel's model? - ✔✔1. Alternative versions
of genes (now called alleles) account for variation in inherited characteristics
2. For each trait, an organism inherits two alleles, one from each parent
3. If the two alleles differ, then one (the dominant allele) determines the organism's
appearance and the other allele (the recessive allele) has no noticeable effect
, 4. The law of segregation: that the two alleles for a heritable character separate
(segregate) during gamete formation and end up in different gametes
✔✔What is the law of independent assortment? - ✔✔Each pair of alleles segregates
independently of other pairs of alleles during gamete formation
✔✔Most genes exist in populations in _____. - ✔✔More than two allelic forms (multiple
alleles)
✔✔In incomplete dominance, offspring can have what? - ✔✔An appearance in between
the phenotype of the two parents
✔✔In codominance, offspring can display what? - ✔✔Two dominant phenotypes at the
same time
✔✔TRUE OR FALSE: The Calvin cycle is light dependent. - ✔✔FALSE
✔✔How do light reactions use the energy of sunlight to make the energy-storing
compounds ATP and NADPH? - ✔✔1. Photons excited electrons in the chlorophyll on
the first photosystem. These photons are trapped by the primary electron acceptor. This
photosystem then replaces the lost electrons by extracting new ones from water. This is
the step that releases O2 during photosynthesis.
2. Energized electrons from the first photosystem pass down an electron transport chain
to the second photosystem. The chloroplast uses the energy released by this electron
"fall" to make ATP
3. The second photosystem transfers its light-excited electrons to NADP+, reducing it to
NADPH.
✔✔During the Calvin cycle within the stoma of the chloroplast, CO2 from the air and
ATP and NADPH produced during the light reactions are used to produce ____, which
can be used to make ____ and _____. - ✔✔G3P, an energy-rich sugar molecule
Glucose
Other organic molecules
✔✔How is C4 photosynthesis different from C3 photosynthesis? - ✔✔C4 plants close
their stomata to save water during hot and dry weather
C3 is traditional
✔✔What is the difference between aerobic and anaerobic respiration? - ✔✔Aerobic
requires oxygen
✔✔The molecules of electron transport chains are built into where? - ✔✔The inner
membranes of mitochondria
