Bio Chapter 9 and 10
Chromosomes are duplicated during the _____ of the cell cycle.
S phase
Which photosynthetic unit consists of a pair of chlorophyll a molecules with an absorption peak of 700 nm?
Photosystem
By definition, substances that absorb visible light are called
Pigments
Which part of the chlorophyll molecule is responsible for absorbing light?
Porphyrin ring
Homologous chromosomes undergo synapsis.
Prophase I
In unwound chromatin, nucleosomes are organized into large coiled loops held together by
scaffolding proteins.
In a human cell at prophase I, there are ______ tetrads.
23
How many carbon fixation reactions make up the Calvin cycle?
3
Thylakoid membranes are involved in synthesis.
ATP
What happens in the second phase of the Calvin cycle?
ATP and NADPH are used to convert the PGA molecules to glyceraldehyde-3-phosphate
Sister chromatids separate and chromosomes move to opposite poles.
Anaphase II
Which of the following is produced by meiosis?
Animal gametes
Which of the following are surrounded by fibrils that make up the pericentriolar material?
Centrioles
At a plant's light compensation point the rate of photosynthesis is greater than the rate of respiration.
False
Cyclic electron transport is different from noncyclic electron transport in that cyclic electron transport produces NADPH.
False
Enzymes required for DNA replication are synthesized during the G1 phase.
False
The photolysis of water occurs in conjunction with photosystem
False
Which type of electromagnetic waves has the shortest wavelength?
Gamma waves
_________ organized on chromosomes carry the information that controls the functions of the cell.
Genes
A group of thylakoid discs make up what part of the chloroplast?
Granum
What color does chlorophyll reflect?
Green
What are the reactants of the light-dependent reactions of photosynthesis?
H20, ADP, and NADP+
An electron absorbs a photon of light energy and becomes energized; the electron shifts from a atomic orbital to atomic orbital.
Lower energy; higher energy
A chlorophyll molecule has a porphyrin ring containing a single atom of
Magnesium
Tetrads line up at the cell equator.
Metaphase I
Which organism would be classified as a chemoautotroph?
Nitrogen fixing bacteria
What is not a hallmark of prophase?
Nuclear envelope is visible with the light microscope.
ATP synthesis during the light-dependent reactions occurs by which process?
Phosphorylation
Which process not only yields electrons that replenish photosystems I and II, but also is the source of almost all the oxygen in Earth's atmosphere?
Photolysis
The energy of a(n) is inversely proportional to its wavelength
Photon
_______ contain identical DNA sequences and are held together by ____ during mitosis.
Sister chromatids; cohesin proteins
In C3 plants, the are typically closed at night and open during the daytime to allow for gas exchange.
Stomata
What is the fluid-filled sac within the inner membrane of a chloroplast called?
Stroma
Nuclear envelope forms around single-stranded chromosomes.
Telophase II
A cell is dividing by binary fission. What can you conclude?
The cell is prokaryotic.
When is a cell in metaphase?
The chromosomes are aligned at the midplane of the cell
Chlorophyll and accessory photosynthetic pigments are associated with which part of the chloroplast?
Thylakoid membranes
An animal zygote is a haploid cell.
True
Bacteria divide asexually by mitosis.
True
CAM plants open their stomata at night, admitting CO2 while minimizing water loss.
True
Cell-eycle checkpoints temporarily block key events from being initiated during the cell cycle.
True
Homologous pairs of chromosomes separate during meiosis I.
True
In the cell cycle, DNA is replicated during the G2 phase.
True
Surrounding the grana is the thylakoid lumen.
True
The product of the Calvin cycle that is of greatest practical importance to the plant is carbohydrate.
True
What is the ultimate source of electrons for noncyclic electron transport, and thus photosynthesis?
Water
To prevent disastrous consequences, the eukaryotic cell cycle is controlled by
a series of cell cycle checkpoints
During prophase I, each chiasma represents
a site of crossing-over.
Cytokinesis in animal cells involves contraction of a ring of microfilaments.
actin plus myosin
Duplicated centrioles move to opposite poles of a dividing _____ cell during the_____ of the cell cycle.
animal; prophase
Cytokinesis in plant cells occurs via the formation of a(n)
cell plate
Eukaryotic chromosomes consist of
circular DNA molecules complexed with negatively charged histone proteins
What is the first step in the Calvin cycle?
co2 attaches to RuBP.
Plant hormones known as stimulate mitosis
cytokinins
Nucleosomes are best described as
eukaryotic DNA associated with histone proteins
When an electron returns to its ground state, energy will be released as heat or as an emission of light, known as
fluorescence
A cell in the G2 phase
has twice the amount of DNA present in a telophase nucleus.
ATP is formed when the thylakoid lumen.
hydrogen ions enter 6.hydrogen ions leave
The cell cycle of a typical somatic cell consists of the ______ and M phases.
interphase
The mitotic spindle is made of
microtubules.
Gametophyte plants produce gametes using
mitosis
haploid spores The is responsible for the separation of the chromosomes during the of mitosis,
mitotic spindle; anaphase
At the completion of oogenesis, ____ are produced.
one egg cell and three polar bodies
The function of nucleosomes is to
prevent DNA strands from tangling.
During prophase I of meiosis, homologous chromosomes lie side by side. This phenomenon is known as
tetrad formation.
Homologous chromosomes can be identified and/or characterized by
their similar and characteristic staining patterns
