chapter 13 Flashcards
Which of the following defines a genome?
D) the complete set of an organism’s genes and other DNA sequences
Asexual reproduction in Eukaryotes occurs during ________.
B) mitosis
Which of the following is a true statement about sexual vs. asexual reproduction?
B) In sexual reproduction, individuals transmit half of their nuclear genes to each of their offspring.
Which of the following is true of a species that has a chromosome number of 2n = 16?
C) Each diploid cell has eight homologous pairs.
In a plant’s sexual life cycle ________.
B) gametophytes produce gametes by mitosis
Which of the following is an example of alternation of generations?
B) A diploid plant (sporophyte) produces, by meiosis, a spore that gives rise to a multicellular, haploid pollen grain (gametophyte).
In a human karyotype, chromosomes are arranged in 23 pairs. If we choose one of these pairs, such as pair 14, which of the following do the two chromosomes of the pair have in common?
C) length, centromere position, staining pattern, and traits coded for by their genes
Homologous chromosomes ________.
B) carry information for the same traits
If meiosis produces haploid cells, how is the diploid number restored for those organisms that spend most of their life cycle in the diploid state?
D) fertilisation
The human X and Y chromosomes ________.
C) include genes that determine an individual’s sex
If a cell has completed meiosis I and is just beginning meiosis II, which of the following is an appropriate description of its contents?
A) It has half the amount of DNA as the cell that began meiosis.
Which of the following happens at the conclusion of meiosis I?
A) Homologous chromosomes of a pair are separated from each other
Sister chromatids separate from each other during ________.
D) mitosis and meiosis II
Which of the following occurs in meiosis but not in mitosis?
B) synapsis of chromosomes
Somatic cells of roundworms have four individual chromosomes per cell. How many chromosomes would you expect to find in an ovum from a roundworm?
B) two
Which of the following can occur by the process of meiosis but not mitosis?
C) Diploid cells form haploid cells.
What is a major difference between meiosis II and mitosis in a diploid animal?
C) Meiosis II occurs in a haploid cell, while mitosis occurs in diploid cells.
Crossing over normally takes place during which of the following processes?
B) meiosis I
For the duration of meiosis I, each chromosome ________.
B) consists of two sister chromatids joined by a centromere
Homologous pairs of chromosomes align opposite of each other at the equator of a cell during ________.
B) meiosis metaphase I
Independent assortment of chromosomes occurs during ________.
A) meiosis I only
For a species with a haploid number of 23 chromosomes, how many different combinations of maternal and paternal chromosomes are possible for the gametes?
D) about 8 million
Independent assortment of chromosomes is a result of ________.
A) the random way each pair of homologous chromosomes lines up at the metaphase plate during meiosis I
When homologous chromosomes cross over, what occurs?
C) Corresponding segments of non-sister chromatids are exchanged.
