The document provides an overview of key concepts in biology related to genetics and cellular reproduction. It defines the laws of segregation and independent assortment. It also describes dominant and recessive traits, multiple alleles, polygenic traits, mitosis, meiosis, the cell cycle, and compares the key differences between mitosis and meiosis.

1. Biology 1- EOC Review

2. - Law of Segregation
- Two alleles will segregate from each other so that
each gamete carries only a single copy of each
allele.
- Law of Independent Assortment
- Genes of different traits can segregate
independently during gamete formation.

3.  Dominant
 Trait is shown/seen
 Must have a CAPITAL letter to be dominant
 Recessive
 Trait is masked or not seen if dominant allele is
present
 Must have a lowercase letter

4.  The heterozygous
phenotype is a blend
between the two
homozygous
phenotypes.
 CRCR= Red flowers
 CRCW= Pink flowers
 CWCW= White flowers

5.  Both alleles are
expressed in the
phenotype

6.  Multiple Alleles
 Genes that have more than two alleles
 More than two possible alleles exists in a population.
Ex- coat color in rabbits (full
color, chinchillas, Himalayan, and albino.
 Polygenic Traits
 Traits that are produced by the interaction of several
genes.
 Show a wide range of traits. Ex- human skin colors.

7.  Somatic cells- a body cell that is not passed
on to future generations.
 Sex or germ cells- a cell that is destined to
become a gamete (egg or sperm).
 Diploid (2N) – a cell with 2 chromosome sets
in each cell; somatic cells.
 Haploid (N) – a cell with 1 chromosome set in
each cell; germ cells.

8.  The cell cycle has two
major stages;
interphase and mitotic
phase (M).
 The longest phase of
the cell cycle is
interphase.
 Consists of 3 stages;
G1, S, and G2.

9.  G1
 Stage where cells spend the most time.
 G- growth phase to prepare for S phase.
 S
 S- synthesis
 Stage of DNA replication
 G2
 G- growth period.
 Prepares cell for mitosis.

10.  Cells that undergo mitosis produce
genetically identical cells (2N).
 Four stages of mitosis
 Prophase
 Metaphase
 Anaphase
 Telophase/Cytokinesis

11.  Beginning of cellular
division
 Chromosomes
condense
 Centrioles migrate to
poles
 Nuclear envelope
disappers.

12.  Chromosomes line up
along the equator
 Centrioles are on
opposite poles of the
cell
 Spindle fibers attach to
the centromeres

13.  The centromeres
divide
 Go from two sister
chromatids to 2
separate
chromosomes
 Spindle fibers pull the
chromosomes to
opposite poles

14.  Telophase
 Chromosomes are at poles
 Nuclear envelope reforms
 Cytokinesis
 Division of cytoplasm
 Cleavage furrow forms to
separate daughter cells
 Cell plate forms in plant
cells (eventually forms cell
wall)

15.  Meiosis occurs in sexual reproduction
 A diploid germ cell produces four haploid daughter
cells that become gametes.
 Have two major stages Meiosis I and Meiosis II.

16.  Chromatids pair and
crossing over occurs.
 Chromosomes
condense
 Spindle fibers form
 Nuclear envelope
disappears

17.  Chromatid pairs line up along the equator
 Spindle fibers attach

18.  Spindle fibers pull
chromosomes to
opposite poles
 Sister chromatids
remain attached

19.  Nuclear envelopes
reassemble
 Spindle fibers
disappear
 Cytokinesis divides cell.

20.  Nuclear envelopes
disappears
 Spindle fibers form

21.  Chromosomes line up
along the equator

22.  Sister chromatids are
separated
 Spindle fibers pull the
separate
chromosomes to
opposite poles

23.  Nuclear envelope
forms
 Spindle fibers
disappear
 Chromosomes unravel
 Cytokinesis divides the
cells
 Have four haploid
daughter cells

24. Mitosis Meiosis
2 identical daughter 4 genetically different
cells daughter cells
Diploid (2N)  diploid Diploid (2N)  haploid
(2N) (N)
Asexual reproduction- Sexual reproduction-
organisms reproduce organism produce
by mitosis gametes

25. Mitosis and meiosis are processes involved in
cellular reproduction. Which of the following
describes an event that results from mitosis but
NOT meiosis?
a. Two stages of cell division
b. Replication of cellular genetic material
c. Daughter cells that are identical to the parent cell
d. Four daughter cells that are produced from each
parent cell

26. Mitosis and meiosis are processes involved in
cellular reproduction. Which of the following
describes an event that results from mitosis but
NOT meiosis?
a. Two stages of cell division
b. Replication of cellular genetic material
c. Daughter cells that are identical to the parent cell
d. Four daughter cells that are produced from each
parent cell

27. Which of the following best compares the processes of
mitosis and meiosis?
a. Mitosis involves one division cycle and results in diploid daughter
cells, while meiosis consists of two division cycles and results in
haploid gametes
b. Mitosis involves one division cycle and results in haploid
gametes, while meiosis consists of two division cycles and results
in diploid daughter cells
c. Mitosis involves two division cycles and results in diploid
daughter cells, while meiosis consists of one division cycle and
results in haploid gametes.
d. Mitosis involves two division cycles and results in haploid
gametes, while meiosis consists of one division cycle and results
in diploid daughter cells.

28. Which of the following best compares the processes of
mitosis and meiosis?
a. Mitosis involves one division cycle and results in diploid daughter
cells, while meiosis consists of two division cycles and results in
haploid gametes
b. Mitosis involves one division cycle and results in haploid
gametes, while meiosis consists of two division cycles and results
in diploid daughter cells
c. Mitosis involves two division cycles and results in diploid
daughter cells, while meiosis consists of one division cycle and
results in haploid gametes.
d. Mitosis involves two division cycles and results in haploid
gametes, while meiosis consists of one division cycle and results
in diploid daughter cells.

29. Which of the following best describes how the process of
crossing over during meiosis leads to an increase in
genetic diversity?
a. During prophase I, DNA replication takes place, and homologous
chromosomes trade places with each other before lining up in
preparation for metaphase
b. During prophase I, DNA segments are exchanged between
homologous chromosomes, resulting in different combinations
of alleles
c. During prophase II, fragments of DNA break off of chromosomes
and attach to the ends of other chromosomes, resulting in
different gene sequences
d. During prophase II, sister chromatids separate from each
other, as they travel to opposite ends of the cell, DNA segments
of nearby chromosomes are exchanged

30. Which of the following best describes how the process of
crossing over during meiosis leads to an increase in
genetic diversity?
a. During prophase I, DNA replication takes place, and homologous
chromosomes trade places with each other before lining up in
preparation for metaphase
b. During prophase I, DNA segments are exchanged between
homologous chromosomes, resulting in different combinations
of alleles
c. During prophase II, fragments of DNA break off of chromosomes
and attach to the ends of other chromosomes, resulting in
different gene sequences
d. During prophase II, sister chromatids separate from each other,
as they travel to opposite ends of the cell, DNA segments of
nearby chromosomes are exchanged

31. The allele for brown eyes is dominant to the allele for
blue eyes. Which of the following best explains how
two brown-eyed parents could produce a blue-eyed
child?
a. Each parent must be carrying the recessive allele for blue
eyes
b. Eye color is a sex-linked trait and male children could have
only the allele for blue eyes
c. Mutations after fertilization could alter gene sequences and
change alleles
d. One parent must have had only blue eyed parents

32. The allele for brown eyes is dominant to the allele for
blue eyes. Which of the following best explains how
two brown-eyed parents could produce a blue-eyed
child?
a. Each parent must be carrying the recessive allele for blue
eyes
b. Eye color is a sex-linked trait and male children could have
only the allele for blue eyes
c. Mutations after fertilization could alter gene sequences and
change alleles
d. One parent must have had only blue eyed parents

33. When an organism has more than 10 fingers or
toes, the condition is known as polydactylism.
Although polydactylism is rare, it is a dominant trait. If
two cats that are heterozygous for polydactylism
mate and have a litter with a total of 12 kittens, how
many of them would you expect more than 10 fingers
or toes?
a. 0
b. 6
c. 9
d. 12

34. When an organism has more than 10 fingers or
toes, the condition is known as polydactylism.
Although polydactylism is rare, it is a dominant trait. If
two cats that are heterozygous for polydactylism
mate and have a litter with a total of 12 kittens, how
many of them would you expect more than 10 fingers
or toes?
a. 0
b. 6
c. 9
d. 12

35. In pea plants, the allele for white flowers is recessive
to the allele for purple flowers. In a generation of pea
plants, 89 plants produced purple flowers and 31
plants produced white flowers. Which of the following
is the best conclusion you can make about the parent
plants of this generation?
a. Both parent plants are heterozygous for flower color
b. Both parent plants were homozygous with purple flowers
c. One parent plant had white flowers and the other was
heterozygous for flower color
d. One parent plant was heterozygous for flower color, and
the other was homozygous with purple flowers

36. In pea plants, the allele for white flowers is recessive
to the allele for purple flowers. In a generation of pea
plants, 89 plants produced purple flowers and 31
plants produced white flowers. Which of the following
is the best conclusion you can make about the parent
plants of this generation?
a. Both parent plants are heterozygous for flower color
b. Both parent plants were homozygous with purple flowers
c. One parent plant had white flowers and the other was
heterozygous for flower color
d. One parent plant was heterozygous for flower color, and
the other was homozygous with purple flowers

37. Meiosis allows a plant to produce offspring
plants with which characteristic?
a. A high rate of random mutations
b. Unique combinations of genetic material
c. Traits identical to those of the parent plant
d. Characteristics adaptive to the plants environment

38. Meiosis allows a plant to produce offspring
plants with which characteristic?
a. A high rate of random mutations
b. Unique combinations of genetic material
c. Traits identical to those of the parent plant
d. Characteristics adaptive to the plants environment

39. Suppose you cross two heterozygous tall pea
plants, both with genotype Tt. What is the probability
that the offspring will display the dominant trait?
a. 100%
b. 75%
c. 50%
d. 25%

40. Suppose you cross two heterozygous tall pea
plants, both with genotype Tt. What is the probability
that the offspring will display the dominant trait?
a. 100%
b. 75%
c. 50%
d. 25%

41. In biology, several different processes make up the
cycles for cell division. In which complete process are
four new cells created from one original cell?
a. Anaphase
b. Meiosis
c. Mitosis
d. telophase

42. In biology, several different processes make up the
cycles for cell division. In which complete process are
four new cells created from one original cell?
a. Anaphase
b. Meiosis
c. Mitosis
d. telophase

43. The process by which cells replicate is very
different than the process by which gametes
are produced. Which of the following do both
processes have in common?
a. Cytokinesis
b. Haploid cells form
c. Crossing-over occurs
d. Homologous chromosomes pair up

44. The process by which cells replicate is very
different than the process by which gametes
are produced. Which of the following do both
processes have in common?
a. Cytokinesis
b. Haploid cells form
c. Crossing-over occurs
d. Homologous chromosomes pair up