Download EOU Chapter 8 Learning Targets

EOU CHAPTER 8
The Cellular Basis of Reproduction and Inheritance
Learning Targets
Connections Between Cell Division and Reproduction
8.1 Compare the parent-offspring relationship in asexual and sexual reproduction.
8.1 Explain why cell division is essential for prokaryotic and eukaryotic life.
8.2 Explain how daughter prokaryotic chromosomes are separated from each other during binary fission.
The Eukaryotic Cell Cycle and Mitosis
8.3 Compare the structure of prokaryotic and eukaryotic chromosomes.
8.4 Describe the stages of the cell cycle. Identify when DNA is replicated, chromo-somes are sorted, and two
new cells are formed.
8.5 List the phases of mitosis and describe the events characteristic of each phase. Recognize the phases of
mitosis from diagrams and micrographs.
8.6 Compare cytokinesis in animal and plant cells.
8.7–8.8 Explain how anchorage, cell density, and chemical growth factors control cell division.
8.9 Explain how cancerous cells are different from healthy cells. Distinguish between benign and malignant
tumors, and explain the strategies behind some common cancer treatments.
8.10 Describe the functions of mitosis.
Meiosis and Crossing Over
8.11 Explain how chromosomes are paired. Distinguish between autosomes and sex chromosomes.
8.12 Distinguish between somatic cells and gametes and between diploid cells and haploid cells.
8.12 Explain why sexual reproduction requires meiosis.
8.13 List the phases of meiosis I and meiosis II and describe the events characteristic of each phase. Recognize
the phases of meiosis from diagrams and micro-graphs.
8.14 Describe the similarities and differences between mitosis and meiosis. Explain how the result of meiosis
differs from the result of mitosis.
8.15–8.17 Explain how independent orientation of chromosomes at metaphase I, random fertilization, and
crossing over contribute to genetic variation in sexually repro-ducing organisms.
Alterations of Chromosome Number and Structure
8.18 Explain how and why karyotyping is performed.
8.19 Describe the causes and symptoms of Down syndrome.
8.20 Define nondisjunction, explain how it can occur, and describe what can result.
8.21 Describe the consequences of abnormal numbers of sex chromosomes.
8.22 Explain how new species form from errors in cell division.
8.23 Describe the main types of chromosomal changes. Explain why cancer is not usually inherited.
anaphase
chromatin
homologous chromosomes
prometaphase
anchorage dependence
asexual reproduction
autosome
benign tumor
binary fission
cancer
carcinoma
cell cycle
anaphase
cell cycle control system
cell division
cell plate centromere
centrosome
chiasma (plural, chiasmata)
chromosome
cleavage furrow
crossing over
cytokinesis
deletion
density-dependent inhibition
diploid cell
Down syndrome
duplication
fertilization
gamete
genetic recombination
growth factor
haploid cell
interphase
inversion
karyotype
meiosis
metaphase
metastasis
mitotic phase (M phase)
leukemia
life cycle
locus (plural, loci)
lymphoma
malignant tumor
mitotic spindle
mitosis
prophase
sarcomas
sex chromosome
sexual reproduction
sister chromatid
somatic cell
telophase
tetrad
translocation
trisomy 21
tumor
zygote
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Lecture Outline
I. Introduction
A. Cancer cells
1. start out as _________________________
2. undergo ___________________________
3. lose the ability to ______________________________
4. run amok, causing disease
B. In a healthy body, cell division allows for
1. __________________
2. the ______________________ of damaged cells
3. ___________________________ from an embryo into an adult
C. In sexually reproducing organisms, eggs and sperm result from mitosis & meiosis
II. Cell Division and Reproduction
A. 8.1 Cell division plays many important roles in the lives of organisms
1. Cell division
a. is ________________________________________
b. requires the __________________________________
c. sorts ______________________________ into the resulting pair of daughter cells.
2. Cell division is used
a. for ______________________ of single-celled organisms,
b. ________________ of multicellular organisms from a fertilized egg into an adult,
c. _______________and _________________________ of cells
d. ______________________________ production
3. Living organisms reproduce by two methods.
a. _______________________________
i. produces offspring that are identical to the original cell or organism and
ii. involves inheritance of all genes from one parent
b. ________________________________
i. produces offspring that are similar to the parents, but show variations in
traits
ii. involves inheritance of unique sets of genes from two parents.
B. 8.2 Prokaryotes reproduce by binary fission
1. _____________(bacteria and archaea) reproduce by ______________ (“dividing in half”).
2. The chromosome of a prokaryote is
a. a ____________________________ DNA molecule associated with proteins
b. much _____________________ than those of eukaryotes.
3. Binary fission of a prokaryote occurs in three stages.
a. ___________________ of the chromosome and ________________ of the copies,
b. ____________________ of the cell and movement of the copies, and
c. _________________________ into two daughter cells.
III. The Eukaryotic Cell Cycle and Mitosis
A. 8.3 The large, complex chromosomes of eukaryotes duplicate with each cell division
1. Eukaryotic cells
a. _______________________ and _______________ than prokaryotic cells,
b. ___________________________
c. store most of their genes on _________________ chromosomes in nucleus.
2. Eukaryotic chromosomes are composed of __________________________ consisting of
a. ______________________________________________
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b. proteins that help maintain the chromosome structure and control the activity of its
genes.
3. To prepare for division, the chromatin becomes
a. highly ________________
b. visible with a microscope.
4. Before a eukaryotic cell begins to divide, it duplicates all of its
chromosomes, resulting in
a. two copies called ___________________________
b. joined together by a narrowed “waist” called the
__________________
5. When a cell divides, the sister chromatids
a. separate from each other, now called
_____________________
b. sort into ____________________________________
B. 8.4 The cell cycle multiplies cells
1. The _________________ is an ordered sequence of events that extends
a. from the time a cell is first formed from a dividing parent cell
b. until its own division.
2. The cell cycle consists of two stages, characterized as follows:
a. ____________________: duplication of cell contents
i. G1—growth, increase in cytoplasm
ii. S—duplication of chromosomes
iii. G2—growth, preparation for division
b. ___________________: division
i. _____________—division of the nucleus
ii. _____________—division of cytoplasm
C. 8.5 Cell division is a continuum of dynamic changes
1. Mitosis progresses through a series of stages.
a. _______________________
b. _______________________
c. _______________________
d. _______________________
e. _______________________
2. Cytokinesis often overlaps telophase.
3. A _______________________ is
a. required to divide the _________________________
b. composed of ________________________
c. produced by ___________________________, structures in the cytoplasm that
i. organize microtubule arrangement and
ii. contain a pair of __________________________ in animal cells.
4. _________________
a. The cytoplasmic contents double,
b. two centrosomes form
c. chromosomes duplicate in the nucleus during the _______________
d. nucleoli, sites of ribosome assembly, are visible.
5. ___________________
a. In the cytoplasm ______________begin to emerge from ______________, forming
the ________________.
b. In the nucleus
i. chromosomes coil and become compact, and
ii. ________________disappear.
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6. ____________________
a. Spindle microtubules reach chromosomes, where they
i. attach at _________________ on the _____________ of sister chromatids
ii. move chromosomes to the center of the cell through associated protein
“motors.”
b. Other ________________________ meet those from the opposite poles.
c. The ________________________ disappears.
7. _____________________
a. The mitotic spindle is fully formed.
b. Chromosomes align at ____________________.
c. ______________ of sister chromatids are facing the opposite poles of the spindle.
8. _____________________
a. Sister chromatids separate at the _________________.
b. Daughter chromosomes are moved to opposite poles of the cell as
i. motor proteins move the chromosomes along the spindle microtubules
ii. kinetochore microtubules shorten.
c. The cell elongates due to lengthening of _______________________________.
9. ______________________
a. The cell continues to elongate.
b. The ______________ forms around chromosomes at each pole, establishing
daughter nuclei.
c. _______________________ and nucleoli reappear.
d. The ___________________disappears.
10. During _________________________, the cytoplasm is divided into separate cells.
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D. 8.6 Cytokinesis differs for plant and animal cells
1. In animal cells, cytokinesis occurs as
a. a _________________ forms from a contracting ring of microfilaments, interacting
with myosin,
b. the cleavage furrow deepens to separate the contents into _______________.
2. In plant cells, cytokinesis occurs as
a. a ______________ forms in the middle, from vesicles containing cell wall material.
b. The cell plate grows outward to reach the edges, dividing the contents
c. Each cell now possesses a plasma membrane and cell wall.
E. 8.7 Anchorage, cell density, and chemical growth factors affect cell division
1. The cells within an organism’s body divide and develop at different rates.
2. Cell division is controlled by
a. the presence of essential nutrients
b. ______________________, proteins that stimulate division
c____________________________, in which crowded cells stop dividing
d. __________________________, the need for cells to be in contact with a solid
surface to divide.
F. 8.8 Growth factors signal the cell cycle control system
1. The _____________________________ is a cycling set of molecules in the cell that
a. trigger
b___________________________ in the cell cycle.
2. Checkpoints in the cell cycle can
a. stop an event or
b. signal an event to proceed.
3. There are three major checkpoints in the cell cycle.
a. _____________________
i. allows entry into the S phase or
ii. causes the cell to leave the cycle,
entering a
nondividing G0 phase.
b. ___________________
c. ____________________
4. Research on the control of the cell cycle is one of the
hottest areas in biology today.
G. 8.9 CONNECTION: Growing out of control, cancer cells produce malignant tumors
1. Cancer currently claims the lives of ________ of the people in the United States and other
industrialized nations.
2. Cancer cells ________________ controls on the cell cycle.
3. Cancer cells
a. divide rapidly, often in the absence of ____________________
b. spread to other tissues through the circulatory system
c. grow without being inhibited by other cells.
4. A _______________ is an abnormally growing mass of body cells.
a. _____________________ remain at the original site.
b. ___________________ spread to other locations, called __________________.
5. Cancers are named according to the organ or tissue in which they originate.
a. _________________________ arise in external or internal body coverings.
b. ________________________ arise in supportive and connective tissue.
c. ________________ and __________________ arise from blood-forming tissues.
6. Cancer treatments
a. Localized tumors can be
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i. removed ___________________ and/or
ii. treated with concentrated ___________________________________
b. Chemotherapy is used for __________________________ tumors.
H. 8.10 Review: Mitosis provides for growth, cell replacement, and asexual reproduction
1. When the cell cycle operates normally, mitosis produces genetically identical cells for
a. _________________
b. __________________ of damaged and lost cells, and
c. ______________________
IV. Meiosis and Crossing Over
A. 8.11 Chromosomes are matched in homologous pairs
1. In humans, _________________ have
a. ________ pairs of homologous chromosomes
and
b. one member of each pair from each parent.
2. The human ______________________ X and Y differ
in size and genetic composition.
3. The other 22 pairs of chromosomes are
_____________________ with the same size and
genetic composition.
4. ___________________________ are matched in
a. length,
b. centromere position, and
c. gene locations.
5. A ________________(plural, loci) is the position of a gene.
6. Different versions of a gene may be found at the same locus on
____________________________ chromosomes.
B. 8.12 Gametes have a single set of chromosomes
1. An organism’s ________________ is the sequence of stages leading
a. from the adults of one generation
b. to the adults of the next.
2. Humans and many animals and plants are ____________, with body cells that have
a. _______________ of chromosomes,
b. __________ from each parent.
3. Meiosis is a process that converts ____________ nuclei to _____________ nuclei.
a. ______________ have two homologous sets of chromosomes.
b. ______________ have one set of chromosomes.
c. Meiosis occurs in the sex organs, producing _____________________________.
4. ______________________ is the union
of sperm and egg.
5. The ________________ has a diploid
chromosome number, one set from each
parent.
6. All sexual life cycles include an
alternation between
a. a diploid stage and
b. a haploid stage.
7. Producing ____________ gametes
prevents the chromosome number from
doubling in every generation.
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C. 8.13 Meiosis reduces the chromosome number from diploid to haploid
1. ___________ is a type of cell division that produces haploid gametes in diploid organisms.
2. Two haploid gametes combine in fertilization to restore the diploid state in the zygote.
3. Meiosis and mitosis are preceded by the duplication of chromosomes. However,
a. _______________ is followed by two consecutive cell divisions, and
b. ___________ is followed by only one cell division.
4. Because in meiosis, __________________ of chromosomes is followed by __________, each
of the four daughter cells produced has a __________________ set of chromosomes.
5. ________________________________ – events occurring in the nucleus.
a. Chromosomes coil and become compact.
b. Homologous chromosomes come together as pairs by ___________________
c. Each pair, with four chromatids, is called _____________________.
d. Nonsister chromatids exchange genetic material by _____________________.
6. _____________________ – Tetrads align at the cell equator.
7. _____________________ – Homologous pairs separate and move toward opposite poles
8. ______________________
a. Duplicated chromosomes have reached the poles.
b. A nuclear envelope re-forms around chromosomes in some species.
c. Each nucleus has the _____________ number of chromosomes.
9. Meiosis II follows meiosis I ___________________________________________.
10. Each of the two haploid products enters meiosis II.
11. _____________________________
a. Chromosomes coil and become compact (if uncoiled after telophase I).
b. Nuclear envelope, if re-formed, breaks up again.
12. _____________________________ – Duplicated chromosomes align at the cell equator.
13. _____________________________
a. Sister chromatids separate, and
b. chromosomes move toward opposite poles.
14. ______________________________
a. Chromosomes have reached the poles of the cell.
b. A nuclear envelope forms around each set of chromosomes.
c. With cytokinesis, __________________ cells are produced.
D. 8.14 Mitosis and meiosis have important similarities and differences
1. Mitosis and meiosis both
a. begin with ______________ parent cells that
b. have chromosomes duplicated during the previous _________________.
2. However, the end products differ.
a. Mitosis produces ________________________________________ daughter cells.
b. Meiosis produces ________________________________________ gametes.
E. 8.15 Independent orientation of chromosomes in meiosis and random fertilization lead to varied
offspring
1. Genetic variation in gametes results from
a. ______________________________ at metaphase I and
b___________________________________.
2. Independent orientation at metaphase I
a. Each pair of chromosomes independently aligns at the cell equator.
b. There is _______________________ of the maternal or paternal chromosome facing
a given pole.
c. The number of combinations for chromosomes packaged into gametes is 2n where
_________________________________________
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3. Random fertilization – The combination of each unique sperm with each unique egg
increases genetic variability.
F. 8.16 Homologous chromosomes may carry different versions of genes
1. Separation of homologous chromosomes during meiosis can lead to genetic differences
between gametes.
a. Homologous chromosomes may have different versions of a gene at the same locus.
b. One version was inherited from the ___________________ and the other came from
the ________________________.
c. Since homologues move to opposite poles during __________________, gametes
will receive either the maternal or paternal version of the gene.
G. 8.17 Crossing over further increases genetic variability
1. __________________ is the production of new combinations of genes due to crossing over.
2. __________________ is an exchange of corresponding segments between separate (nonsister) chromatids on homologous chromosomes.
a. Nonsister chromatids join at a ________________ (plural, chiasmata), the site of
attachment and crossing over.
b. Corresponding amounts of genetic material are exchanged between maternal and
paternal (nonsister) __________________.
V. Alterations of Chromosome Number and Structure
A. 8.18 A karyotype is a photographic inventory of an individual’s chromosomes
1. A ____________________ is an ordered display of magnified images of an individual’s
chromosomes arranged in pairs.
2. Karyotypes
a. are often produced from dividing cells arrested at ________________ of mitosis
b. allow for the observation of
i. _____________________________
ii._____________________________
iii. ____________________________
B. 8.19 CONNECTION: An extra copy of chromosome 21 causes Down syndrome
1. _______________
a. involves the inheritance of three copies of chromosome 21 and
b. is the most common human chromosome abnormality.
2. Trisomy 21, called ____________, produces a characteristic set of symptoms, which include:
a. mental retardation,
b. characteristic facial features,
c. short stature,
d. heart defects,
e. susceptibility to respiratory infections, leukemia, and Alzheimer’s disease, and
f. shortened life span.
3. The incidence increases with __________________________.
C. 8.20 Accidents during meiosis can alter chromosome number
1. _____________________ is the failure of chromosomes or chromatids to separate normally
during meiosis. This can happen during
a______________, if both members of a homologous pair go to one pole or
b. _____________ if both sister chromatids go to one pole.
2. Fertilization after nondisjunction yields zygotes with altered numbers of chromosomes.
D. 8.21 CONNECTION: Abnormal numbers of sex chromosomes do not usually affect survival
1. _________________________ abnormalities tend to be less severe, perhaps because of
a. the small size of the _____ chromosome or
b. ______-chromosome inactivation.
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2. Table 8.21 in the textbook lists the most common human sex chromosome abnormalities. In
general
a. a single _____________ is enough to produce “maleness” even in combination with
several X chromosomes, and
b. the absence of a Y chromosome yields “_________________”
E. 8.22 EVOLUTION CONNECTION: New species can arise from errors in cell division
1. Errors in mitosis or meiosis may produce _________________ species, with more than two
chromosome sets.
2. The formation of _________________ species is
a. widely observed in many plant species but
b. less frequently found in animals.
F. 8.23 CONNECTION: Alterations of chromosome structure can cause birth defects and cancer
1. Chromosome breakage can lead to rearrangements that can produce
a. ________________________
b. if changes occur in somatic cells, _________________
2. These rearrangements may include
a. __________________, the loss of a chromosome segment,
b. _________________, the repeat of a chromosome segment,
c. _________________, the reversal of a chromosome segment, or
d. _________________ the attachment of a segment to a nonhomologous
chromosome that can be reciprocal.
3. Chronic myelogenous leukemia (CML)
a. is one of the most common leukemias,
b. affects cells that give rise to white blood cells (leukocytes), and
c. results from part of ____________________ switching places with a small fragment
from a tip of _________________________.
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