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Big Idea 3 Test Review - Class Pages
Big Idea 3 Test Review - Class Pages

... › You MAY NOT say, spell, or ‘sounds like’ any part of any word on the board. There may be some rounds where I restrict other words.  The first team to guess correctly gets the point. ...
Name Date ________Block
Name Date ________Block

... A human somatic cell contains how many homologous chromosomes? ...
Chapter 10
Chapter 10

... • Protein and organelle production increased • Gather and synthesize nutrients – ex. Make the 6 billion nucleotides needed to replicate the DNA. Acquire/synthesize enough amino acids to build all the required proteins to divide the cell, etc… Cells can hang in this subphase for a very long time like ...
Polygenic Traits
Polygenic Traits

... • Mothers older than 35 have rapidly increasing risk. – 95% of non-disjunctions occur with the ovum. • Most Down syndrome babies are born to women younger than 35 because those are the ages that most women have children. • Dogma: all your oocytes are present at birth; meiosis is arrested in Prophase ...
Chapter Three The Biological Basis of Life
Chapter Three The Biological Basis of Life

... Referring to members of chromosome pairs. Homologous chromosomes carry genes that govern the same traits. During meiosis, homologous chromosomes pair and exchange segments of DNA. ...
Chapter 9 Power Point
Chapter 9 Power Point

... Diploid cells (2n) have 2 sets of chromosomes (somatic cells- almost all cells in the body) Haploid cells (n) have one set of chromosomes (gametes or sex cells) ...
Differentiation in Germline Cells
Differentiation in Germline Cells

... • Mutations in germline cells are passed onto offspring. – For example: Cystic Fibrosis • A gene mutation on chromosome 7 may become the recessive form (leading to production of thick and sticky mucus). This mutant allele is passed onto gametes during meiosis. If the other parent is a carrier of the ...
Human Genetics and Pedigrees
Human Genetics and Pedigrees

...  If two copies of an autosomal chromosome fail to separate during meiosis, an individual may be born with three copies of a chromosome.  This is known as a trisomy.  Three copies of chromosome number 21.  Produces mild to severe mental retardation and characterized by an increased susceptibility ...
unit 4 – syllabus - Effingham County Schools
unit 4 – syllabus - Effingham County Schools

... Vocabulary terms to know in order to discuss the Kingdom Plantae: ...
mitosis
mitosis

... “HOMEWORK or LABORATORY TITLE” ___________________________________________________ ___________________________________________________ ...
Ch 8 Review Sheet - Mr. Swords` Classes
Ch 8 Review Sheet - Mr. Swords` Classes

... The following are short definitions, but students were to draw a picture that represents the process or idea. The pictures need not be related to cells. For example, a student could draw two stick figures having a tug-of-war with a rope. The rope could represent spindle fibers. The stick figures cou ...
Gral Regents Review Part 2
Gral Regents Review Part 2

... Gametes carry ½ the chromosomes of body cells and are genetically different. Recombinations occur when gametes form and at fertilization. ...
Biology 2
Biology 2

... MITOSIS: The Five Stages of Division 1. Interphase – it is a period of growth when the cell synthesizes new molecules and organelles. The cell contains two microtubule – organizing centers (MTOC’s), which are clouds of cytoplasmic material that contain centrioles. 2. Prophase – Within the nucleus, t ...
Cell Division (aka Mitosis)
Cell Division (aka Mitosis)

... • When external chemical or physical signals (growth regulators) stimulate or inhibit growth and division ...
cell cycle
cell cycle

... Chromosome – one long DNA molecule; condensed and clearly visible during cell division Chromatid – two identical DNA molecules attached by a centromere (sister chromatids) ...
CELL DIVISION and REPRODUCTION
CELL DIVISION and REPRODUCTION

... Exceptions to the rule that all chromosomes are part of a homologous pair may be found with the sex chromosomes – in humans, it is the X and Y. Human females have a homologous pair of chromosomes, XX, but males have one X chromosome and one Y chromosome. Nonsex chromosomes; that is, all the chromoso ...
Genetics
Genetics

... the sex of their offspring. Males can contribute an X or a Y chromosome toward the sex of their offspring. Absence of an Y chromosome results in a the embryo developing into a female. Presence of an Y chromosome results in the embryo developing into a male. ...
Chapter 14 Human Genetics
Chapter 14 Human Genetics

... Chapter 14 Human Genetics ...
Preview Sample 1
Preview Sample 1

... 31) List in order of occurrence the phases of (a) mitosis and (b) prophase I of meiosis. Answer: (a) prophase, prometaphase, metaphase, anaphase, telophase (b) leptonema, zygonema, pachynema, diplonema, diakinesis ...
My comments/additions/corrections are in BOLDFACE
My comments/additions/corrections are in BOLDFACE

... ANS: Chromosome disjunction occurs during anaphase I. Chromatid disjunction occurs during anaphase II. FEEDBACK: 2.3 DIFFICULTY: easy 2.16 In flowering plants, is sporophytic tissue haploid or diploid? How many nuclei are present in the female gametophyte? How many are present in the male gametophyt ...
Name:
Name:

... 7. Based on your data, what can you infer about the relative length of time an onion root tip cell spends in each stage of mitosis? Be sure to discuss each stage! ...
Mitosis in Onion Root Tip Cells Lab
Mitosis in Onion Root Tip Cells Lab

... The genetic information of plants, animals and other eukaryotic organisms resides in several (or many) individual DNA molecules, or chromosomes. For example, each human cell possesses 46 chromosomes, while each cell of an onion possesses 8 chromosomes. All cells must replicate their DNA when dividin ...
3. Mitosis
3. Mitosis

... • One chromosome of each such pair now moves along the spindle to opposite poles of the mitotic spindle. ...
Strand V Review
Strand V Review

... •During meiosis the cells goes through division TWICE! •At the end of meiosis there are 4 daughter cells that are haploid. •The daughter cells have HALF the normal number of chromosomes. Symbolically this is known as n. ...
lecture notes-microbiology-3-Eucaryotes
lecture notes-microbiology-3-Eucaryotes

... In Meiosis - The diploid cell's chromosomes (DNA) is replicated once and separated twice, producing four sets of haploid cells each containing half of the original cell's chromosomes. - These resultant haploid cells will fertilize with other haploid cells of the opposite gender to form a diploid cel ...
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Meiosis



Meiosis /maɪˈoʊsɨs/ is a specialized type of cell division which reduces the chromosome number by half. This process occurs in all sexually reproducing single-celled and multi-celled eukaryotes, including animals, plants, and fungi. Errors in meiosis resulting in aneuploidy are the leading known cause of miscarriage and the most frequent genetic cause of developmental disabilities. In meiosis, DNA replication is followed by two rounds of cell division to produce four daughter cells each with half the number of chromosomes as the original parent cell. The two meiotic divisions are known as meiosis I and meiosis II. Before meiosis begins, during S phase of the cell cycle, the DNA of each chromosome is replicated so that it consists of two identical sister chromatids. In meiosis I, homologous chromosomes pair with each other and can exchange genetic material in a process called chromosomal crossover. The homologous chromosomes are then segregated into two new daughter cells, each containing half the number of chromosomes as the parent cell. At the end of meiosis I, sister chromatids remain attached and may differ from one another if crossing-over occurred. In meiosis II, the two cells produced during meiosis I divide again. Sister chromatids segregate from one another to produce four total daughter cells. These cells can mature into various types of gametes such as ova, sperm, spores, or pollen.Because the number of chromosomes is halved during meiosis, gametes can fuse (i.e. fertilization) to form a zygote with a complete chromosome count containing a combination of paternal and maternal chromosomes. Thus, meiosis and fertilization facilitate sexual reproduction with successive generations maintaining the same number of chromosomes. For example, a typical diploid human cell contains 23 pairs of chromosomes (46 total, half of maternal origin and half of paternal origin). Meiosis produces haploid gametes with one set of 23 chromosomes. When two gametes (an egg and a sperm) fuse, the resulting zygote is once again diploid, with the mother and father each contributing 23 chromosomes. This same pattern, but not the same number of chromosomes, occurs in all organisms that utilize meiosis. Thus, if a species has 30 chromosomes in its somatic cells, it will produce gametes with 15 chromosomes.
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