Biology 1407 Lesson 7 Review
True or false? There are no known animal species that reproduce asexually.
false Some animals are capable of asexual reproduction. Hydras (Class Hydrozoa) and corals (Class Anthozoa) are examples of animals that are able to reproduce both sexually and asexually by budding. There are many others that are also able to produce eggs asexually, including a few vertebrates.
True or false? The sperm contributes genetic material and cytoplasm to the fertilized egg cell.
false The sperm functions to provide genetic material to the fertilized egg, but it does not contribute cytoplasm.
True or false? The spermatogonium undergoes the first meiotic division to produce the primary spermatocyte.
false The spermatogonium undergoes DNA replication and may develop into the primary spermatocyte through a mitotic division, which is a diploid cell that enters meiosis I.
After ovulation, the __________ becomes the corpus luteum.
follicle After ovulation, the ovum is released into the fallopian tube (oviduct) and eventually travels to the uterus. The remaining follicular tissue becomes the corpus luteum.
In sexual reproduction
gametes are usually haploid. In sexual reproduction gametes are usually haploid cells. Haploid cells result from the reductive division of a diploid cell called meiosis. During meiosis a cell with two sets of each chromosome goes through two divisions to produce cells that are haploid (they have one set of each chromosome).
Which of the following physical properties does not assist in the movement of water through a plant?
gravity
An animal cell with one set of chromosomes rather than two has a ______________ chromosome number.
haploid Cells with one set of chromosomes rather than two are referred to as haploid cells. Haploid cells arise from the meiotic division of diploid cells.
A diploid cell with 16 chromosomes
has 8 chromosome pairs. A diploid cell with 16 chromosomes has 8 chromosome pairs. Diploid cells have homologous chromosome pairs. The chromosomes within a pair of homologues carry genes that control the same traits. If a diploid cell has 16 chromosomes then it has 8 pairs of homologous chromosomes.
The chiasma connects a pair of:
homologous chromosomes during meiosis I. A chiasma links a pair of homologous chromosomes during meiosis I. A chiasma is a region where the genetic material is exchanged between the two chromosomes.
During anaphase I of meiosis
homologous chromosomes separate and migrate to opposite poles. During anaphase I homologous chromosomes separate and migrate to opposite poles. After cytokinesis, each cell produced will have one of each homologous chromosome.
Which of the following hormones produced by the anterior pituitary gland help regulate the menstrual cycle? i. follicle-stimulating hormone (FSH) ii. lutenizing hormone (LH) iii. growth hormone (GH) iv. prolactin
i, ii FSH and LH help to regulate the menstrual cycle by stimulating the activities of the ovaries.
Sperm cells are created in a process of cellular replication called
meiosis. Sperm are produced in a type of cellular reproduction called meiosis. Meiosis involves the division of a cell to produce cells with half the number of chromosomes as the parent cell.
At the base of the flagellum, where it attaches to the head of the sperm is
mitochondria to provide energy for movement of the sperm. The middle piece of the sperm contains the mitochondria, which provides energy in the form of ATP for movement of the tail (flagellum).
Crossing over can contribute to genetic variation by exchanging genetic material between
nonsister chromatids of homologues. Crossing over involves the exchange of genetic material between nonsister chromatids of homologous chromosomes. Crossing over takes place during prophase I of meiosis.
Estrogen is secreted throughout the menstrual cycle by the
ovaries. Estrogen is secreted throughout the menstrual cycle by the ovaries.
Meiosis in the female occurs in which organ?
ovary Meiosis in females occurs in the ovaries. The ovaries produce female gametes (ova) and release reproductive hormones.
The ovum is fertilized in the
oviduct. The ovum is fertilized in the oviduct, and is then transported to the uterus where the fertilized egg will develop.
Which of the following hormones do not have a concentration peak around day 14 of the menstrual cycle?
progesterone Progesterone peaks during the luteal phase of the menstrual cycle, after day 14.
During oogenesis, which cell must be fertilized to complete meiosis?
secondary oocyte The secondary oocyte must be fertilized to complete meiosis and become an egg. If the secondary oocyte is not fertilized, meiosis will not be completed.
By convention, when refering to the mestrual cycle, day 0 is
the first day of menstrual flow. By convention, day 0 is considered the first day of the menstrual cycle.
Flowering in plants is controlled by
the length of the night.
Meiosis in animals serves all but which one of the following functions?
the production genetically identical daughter cells Meiosis in animals does not result in the production of genetically identical daughter cells. The cells that result from meiosis are both genetically different from each other and from the parental cell.
The purpose of the formation of polar bodies is
to conserve cytoplasm in the developing oocyte for the egg cell. The purpose of polar body formation is to conserve cytoplasm for the oocyte. If fertilized, the oocyte will develop into an egg cell, which will depend on components in the cytoplasm for its development. The polar bodies will get very little cytoplasm and will eventually degenerate.
Sequences of a gene that can move from one location to another are
transposons
True or false? All diploid cells have homologous chromosomes.
true Diploid cells (2n) are those that have two sets of each chromosome, while haploid cells have only one set.
True or false? Homologous chromosomes randomly align at the metaphase plate during meiosis.
true Homologous chromosomes randomly align along the metaphase plate during meiosis.
True or false? In female germ cells, prophase I begins in early fetal development and ends years later.
true In early fetal development, a female has about a million primary oocytes arrested in prophase I within each ovary. Many of these cells will degenerate, but during the female's reproductive years, approximately one primary oocyte per month will complete prophase I to become a secondary oocyte.
Match the following hormones with their role in the menstrual cycle. estrogen LH FSH stimulates follicular growth stimulates proliferation of the endometrium stimulates secretion of progesterone stimulates secretion of estrogen
1. b 2. c, d 3. a, d Estrogen stimulates the proliferation of the endometrium. LH and FSH both stimulate the production of estrogen, but LH is primarily responsible for increasing the secretion of progesterone while FSH stimulates follicular growth.
The average menstrual cycle is __________ long.
28 days The average menstrual cycle is 28 days, and includes menstruation as well as the time between periods.
If we count copies (c) of DNA, what do we start and end with in the process of meiosis?
4c to 1c We start with four chromatids per chromosome and end up with one chromatid.
Which of the following statements regarding spermatogenesis is false?
Spermatogenesis of one primary spermatocyte results in four sperm cells that are genetically identical. A single spermatogonium produces four haploid cells, but they are not genetically identical to each other because they result from meiosis. Meiosis produces four non-identical haploid cells.
Which of the following statements is not true regarding independent assortment?
The arrangement of chromosomes before synapsis determines how chromosomes will be separated. The arrangement of chromosomes along the metaphase plate determines how chromosomes will be separated.
Which of the following statements about differences between the estrous cycle and the menstrual cycle is not true?
The estrous cycle is controlled by pheremones while the the menstrual cycle is controlled by hormones. While pheremones do play a role in the estrous cycle, both the estrous cycle and the menstrual cycle are controlled by hormones.
Which statement regarding oogenesis is correct?
The polar bodies will degenerate. The polar bodies that are generated during oogenesis will eventually breakdown.
Which of the following statements regarding homologous chromosomes is true?
They have genes for the same traits. Homologous chromosomes have the same genes but may have slightly differing versions (alleles) for those genes.
James Watson and Francis Crick were the first scientists to
accurately describe the molecular structure of DNA.
Homologous chromosomes separate and migrate to opposite poles during
anaphase I. Homologous chromosomes separate and move to opposite poles during anaphase I of meiosis.
Sister chromatids of each chromosome separate and move to opposite poles during
anaphase II. Sister chromatids separate and move to opposite poles during anaphase II of meiosis.
Yeast, a single-celled fungi, often replicates by pinching off into two unequal sized cells. This process is called
budding. Budding is a type of asexual reproduction that involves the pinching off of an outgrowth from the parent organism to form an independent organism that has the same genetic make-up of the parent.
The centromere is the location where
chromatids are attached to one another. The centromere is a region where chromatids of chromosomes are attached to each other. The microtubules of the spindle attach at the centromere of chromosomes during mitosis and meiosis.
The tip of a plant that responds to light stimulus is called the
coleoptile
Progesterone is secreted after ovulation by the
corpus luteum. Progesterone is secreted after ovulation by the corpus luteum.
Homologous chromosomes originate
during fertilization. Homologous chromosomes arise after fertilization. Each parent contributes a haploid cell that has one of each chromosome. After fertilization the resulting cell will have two of each chromosome.
True or false? A synapsis is the X-like formation that represents an exchange of genetic material between chromatids on homologous chromosomes.
false Chiasmata is the term to describe the X-like formation that represents an exchange of genetic material between homologous chromosomes.
True or false? Homologous chromosomes are attached at the centromere.
false Sister chromatids are attached at the centromere. Homologous chromosomes have the same gene loci, but may have different alleles for those genes. Homologous chromosomes are attached to one another during synapsis of meiosis.
__________ cells do not directly take part in sexual reproduction, while __________ cells do.
Somatic; germ Somatic cells are all cells of the body. Somatic cells do not take part in sexual reproduction. Germ cells are gametes, cells that do take part in sexual reproduction.
If a cell has a diploid number of six chromosomes, and crossing over does not take place between the homologous chromosomes, how many different chromosomal combinations are possible in the resulting daughter cells after meiosis? (Each homologous pair consists of a maternal chromosome and a paternal chromosome).
8 There will be eight possible chromosomal combinations resulting from an organism with a diploid number of six. Each homologous pair consists of two chromosomes that can be separated into two different daughter cells (thus there are two possible combinations for each homologous pair). A cell with a dipoid number of six has three homologous pairs of chromosomes. The different types of daughter cells that can result from meiosis are 2 × 2 × 2 = 8.
The menstrual cycle is regulated by hormone secretions of the
A and C The menstrual cycle is regulated by hormone secretions of the ovaries and pituitary glands. The ovaries secrete estrogens and progesterone, while the anterior pituitary gland secretes follicle-stimulating hormone (FSH) and lutenizing hormone (LH).
Which of the following acts as a hormone in plants?
Auxins and Gibberellins Ethylene and abscisic acid All of these
Which of the following ranks the structures in order of size from largest to smallest?
Chromosome,gene,codon,nucleotide.
The attachment of -CH3 to DNA bases to effect long-term DNA inactivation is called
DNA methylation.
Which statement regarding disjunction is false?
Disjunction occurs only during anaphase II of meiosis. Disjunction also occurs during meiosis I with the separation of the homologous pairs.
Which of the following is not a function of estrogen?
Estrogen signals the corpus lueteum to produce progesterone. LH stimulates the corpus leuteum to produce progesterone.
Who first extracted nucleic acid (DNA) from white blood cells?
Friedrich Miescher
What hormone maitains the uterine lining after fertilization?
HCG The fetus produces HCG a LH mimic, which stimulates the corpus luteum to continue producing progesterone and estrogen, which causes the maintenance of the endometrial lining.
Which statement regarding homologous chromosomes is not correct?
Homologous chromosomes have identical alleles. Homologous chromosomes don't have to have identical alleles for each gene, although they can. For example, a set of homologous chromosomes may have a gene for hair color, but each chromosome may have a different allele for that hair color gene (brown vs. blond hair).
Which statement regarding meiosis is true?
Homologous chromosomes separate during anaphase I. This statement is true. During anapahse I, homologous chromosomes separate from one another.
Which statement regarding independent assortment is true?
Independent assortment is the result of the random orientation of homologous pairs of chromosomes along the metaphase plate. Since homologous chromosomes randomly align along the metaphase plate, there is a fifty-fifty chance that a daughter cell will get a particular chromosome from each homologous pair.
Bacteria most commonly reproduce by a method called
Neither A nor B. Most bacterial cells replicate by a method called binary fission. This process involves the doubling of the bacterium's chromosome and the division of the cell to form two cells identical to the parent cell.
_____ are pigments involved in the flowering response of plants to light.
Phytochromes
All of the following are functions of meiosis except:
Production of identical daughter cells. The purpose of meiosis is to form haploid cells from diploid cells. The haploid cells that result will not be identical to the parent cell that produced them or to each other. During prophase of meiosis I, genes on homologous chromosomes are shuffled in a process called crossing over. Haploid cells called gametes will be able to take part in sexual reproduction.
Which type of cell nourishes and protects developing sperm cells?
Sertoli cells Sertoli cells are present in the tissues of the seminiferous tubules and protect and nourish developing sperm cells.
