AS Biology Unit 3: Cell Cycle, Meiosis, and Reproduction

This allows for the possibility of having different alleles of the same gene, one inherited from each parent.

They represent the long coiled DNA molecule in one chromosome.

A homozygous individual has two identical alleles of a gene, while a heterozygous individual has two different alleles of a gene.

<p>During cell division, specifically during mitosis.</p> Signup and view all the answers

<p>They are exact replicas of each other, containing the same alleles.</p> Signup and view all the answers

<p>Chromatin is the DNA-histone complex present during interphase, while a chromosome is the compact, X-shaped form of chromatin visible during mitosis.</p> Signup and view all the answers

<p>The cell cycle is a regulated process in which cells divide into two identical daughter cells, and it consists of three main stages: interphase, mitosis, and cytokinesis.</p> Signup and view all the answers

<p>Mitosis contributes to growth, repair, and asexual reproduction.</p> Signup and view all the answers

<p>The result of meiosis is haploid gametes.</p> Signup and view all the answers

<p>Polysomy is a condition where there are three or more sets of chromosomes, and an example of a condition that results from this is Down's syndrome.</p> Signup and view all the answers

<p>Monosomy is a condition where there is a single set of chromosomes, and an example of a condition that results from this is Turner's syndrome.</p> Signup and view all the answers

<p>The cell cycle plays a crucial role in the development of an organism by allowing for growth, repair, and reproduction. If it were not regulated, it could lead to uncontrolled cell growth and potentially cancer.</p> Signup and view all the answers

<p>To introduce genetic variation, which allows species to adapt to their environment and evolve.</p> Signup and view all the answers

<p>One</p> Signup and view all the answers

<p>Maternal and paternal alleles can be combined despite being on physically different chromosomes.</p> Signup and view all the answers

<p>They hold the bivalent together</p> Signup and view all the answers

<p>It allows species to adapt to their environment and evolve.</p> Signup and view all the answers

<p>Prophase I</p> Signup and view all the answers

<p>A fault in anaphase, where the chromatids or chromosomes fail to separate and move to opposite poles.</p> Signup and view all the answers

<p>The resulting zygote will have the wrong number of chromosomes.</p> Signup and view all the answers

<p>Trisomy is the presence of three copies of a chromosome instead of two, occurring when a gamete with an extra chromosome is fertilized by a normal gamete.</p> Signup and view all the answers

<p>Trisomy 21, which causes Down syndrome, is the exception.</p> Signup and view all the answers

<p>Down syndrome, which has severe consequences on the individual's phenotype.</p> Signup and view all the answers

<p>Anaphase I or anaphase II.</p> Signup and view all the answers

<p>Monosomy; the exception is the X chromosome, as seen in Turner syndrome.</p> Signup and view all the answers

<p>Diploid; triploid.</p> Signup and view all the answers

<p>About 1 in 5000; they appear female.</p> Signup and view all the answers

<p>X0 individuals have one copy of the X chromosome, while normal females have two copies.</p> Signup and view all the answers

<p>Apples; very common.</p> Signup and view all the answers

<p>Little adverse effect; monosomy is usually fatal, whereas polyploidy has a minimal impact on the phenotype.</p> Signup and view all the answers