• Study Resource
  • Explore Categories
    • Arts & Humanities
    • Business
    • Engineering & Technology
    • Foreign Language
    • History
    • Math
    • Science
    • Social Science

    Top subcategories

    • Advanced Math
    • Algebra
    • Basic Math
    • Calculus
    • Geometry
    • Linear Algebra
    • Pre-Algebra
    • Pre-Calculus
    • Statistics And Probability
    • Trigonometry
    • other →

    Top subcategories

    • Astronomy
    • Astrophysics
    • Biology
    • Chemistry
    • Earth Science
    • Environmental Science
    • Health Science
    • Physics
    • other →

    Top subcategories

    • Anthropology
    • Law
    • Political Science
    • Psychology
    • Sociology
    • other →

    Top subcategories

    • Accounting
    • Economics
    • Finance
    • Management
    • other →

    Top subcategories

    • Aerospace Engineering
    • Bioengineering
    • Chemical Engineering
    • Civil Engineering
    • Computer Science
    • Electrical Engineering
    • Industrial Engineering
    • Mechanical Engineering
    • Web Design
    • other →

    Top subcategories

    • Architecture
    • Communications
    • English
    • Gender Studies
    • Music
    • Performing Arts
    • Philosophy
    • Religious Studies
    • Writing
    • other →

    Top subcategories

    • Ancient History
    • European History
    • US History
    • World History
    • other →

    Top subcategories

    • Croatian
    • Czech
    • Finnish
    • Greek
    • Hindi
    • Japanese
    • Korean
    • Persian
    • Swedish
    • Turkish
    • other →
 
Profile Documents Logout
Upload
Cell Cycle, Mitosis and Meiosis
Cell Cycle, Mitosis and Meiosis

... These steps can be divided into two main components: interphase and the mitotic phase. Interphase is the stage when the cell mostly performs its “everyday” functions. For example, it is when a kidney cell does what a kidney cell is supposed to do. The cell also gets ready to divide during this time. ...
Unisexual reproduction in Vertebrates AP Biology Extra Credit
Unisexual reproduction in Vertebrates AP Biology Extra Credit

... explain what this means. ...
The Cell Cycle and Cell Division
The Cell Cycle and Cell Division

... Meiosis I is preceded by an S phase during which DNA is replicated. Each chromosome then consists of two sister chromatids. At the end of meiosis I, two nuclei form, each with half the original chromosomes (one member of each homologous pair). The centromeres did not separate, so each chromosome is ...
3 The Cell Cycle
3 The Cell Cycle

... always have more chromosomes than simpler eukaryotes. For example, potatoes have 48 chromosomes, but humans have 46. Many eukaryotes, including humans, have pairs of similar chromosomes. These pairs are called homologous chromosomes. One chromosome in a pair comes from each parent. Cell division in ...
Sordaria
Sordaria

... inherited chromosomes will swap genetic material. At the end of the process, each chromosome will consist of a patchwork of genes from both mother and father. Essentially, each chromosome will be “shuffled” so that entirely new gene combinations will be present on each chromosome. Fungi are generall ...
Module B Keystone Practice Problems answers File
Module B Keystone Practice Problems answers File

... that causes hemophilia is located on the X-chromosome. Given this information, which of the following statements is true? a. In order for a male offspring to be a hemophiliac, his mother must be a hemophiliac. b. In order for a female offspring to be a hemophiliac, her father must be a hemophiliac. ...
Chapter 3 – Cell Structure and Function
Chapter 3 – Cell Structure and Function

... - The sequence of nucleotides in DNA creates a code for building proteins. - RNA carries out these instructions, reads the code and puts the amino acids together to make the proteins. Those proteins become traits (hair, eyes, bones) RNA is a nucleic acid like DNA but it is different: - the sugar in ...
Chapter 7 – Linkage, Recombination, and
Chapter 7 – Linkage, Recombination, and

... • Cis configuration/coupling – Both wildtype alleles are on one chromosome; both mutant alleles are on the homologous chromosome ...
AP Bio Summer Work Reading Guide (2013 - 2014).
AP Bio Summer Work Reading Guide (2013 - 2014).

... a. What happens to chromosome number in meiosis? b. During which division is the chromosome number reduced? c. What is the purpose of meiosis? d. How many times does the cell divide in meiosis? e. How many times do the chromosomes duplicate? f. ...
Pierce chapter 7
Pierce chapter 7

... – Between genes on different chromosomes – Independent assortment/random segregation during Metaphase/Anaphase I – Produces 50% recombinant/50% non-recombinant ...
APBioSummerWorkReadingGuide_2014_2015
APBioSummerWorkReadingGuide_2014_2015

... a. What happens to chromosome number in meiosis? b. During which division is the chromosome number reduced? c. What is the purpose of meiosis? d. How many times does the cell divide in meiosis? e. How many times do the chromosomes duplicate? f. ...
Name
Name

... Harmless organisms could be genetically engineered to recognize and destroy A. random cells in the body. Disease-causing organisms could be genetically engineered to produce insulin B. instead of toxins. Harmless organisms could be genetically engineered to have surface proteins from C. disease-caus ...
Keystone Review Packet Selected Topics Winter 2015 #4 Keystone
Keystone Review Packet Selected Topics Winter 2015 #4 Keystone

... that causes hemophilia is located on the X-chromosome. Given this information, which of the following statements is true? a. In order for a male offspring to be a hemophiliac, his mother must be a hemophiliac. b. In order for a female offspring to be a hemophiliac, her father must be a hemophiliac. ...
S phase
S phase

... distinct stages: interphase, mitosis, and cytokinesis. Interphase is the period between successive rounds of nuclear division and is distinguished by cellular growth and new synthesis of DNA. ...
Indicate the answer choice that best completes the
Indicate the answer choice that best completes the

...        1. Which of the following would be least likely to happen as a result of a mutation in a person's skin cells? a. skin cancer b. reduced functioning of the skin cell c. no change in functioning of the skin cell d. the person's offspring have mutated skin        2. How can cancer cells be descr ...
The Cell Cycle and Mitosis
The Cell Cycle and Mitosis

... slightly different. For example, in animal cells the cytoplasm is pinched and separated during cytokinesis and in plants a cell plate forms to separate the cytoplasm. ...
DNA
DNA

... controlling traits that are passed to an offspring • Replication – creation of new exact copies of DNA to be used in newly made cells Packet page # ...
labskillstest2handou..
labskillstest2handou..

... What are characteristics of green algae and multicellular land plants that suggest green algae are ancestral to plants? List 3 characteristics. Euglena is unicellular and contains chlorophyll. So does Chlamydamonas. But, Euglena is not considered to be algae. Why? ----------------------------------- ...
INHERITANCE
INHERITANCE

... Inheritance is the passage of hereditary traits from one generation to the next. It is the process by which you acquired your characteristics from your parents and transmit some of your traits to your children. The branch of biology that deals with inheritance is called genetics. Genotype and Phenot ...
Handout
Handout

... Types of Mutations Some mutations affect a single gene, while others affect an entire chromosome. A __________________________________ affects a single gene.  Many kinds of mutations can occur, especially during replication. Types of Gene Mutations:  A ________________________________________ subs ...
File
File

...  Spindle fibers from centromere to centrioles Anaphase:  Sister Chromatids split at Centromere  Individual Chromosomes move toward poles  Chromatid pairs from each chromosome separate from each other  Chromatids are pulled apart by the shortening of the microtubules in the spindle fibers Teloph ...
Animal Reproduction and Genetics
Animal Reproduction and Genetics

... and extend from the centromeres. – Metaphase- spindle fibers align the chromosomes along the middle of the cell nucleus. ...
Chapter 24 - S3 amazonaws com
Chapter 24 - S3 amazonaws com

... 1. Like all plants, the life cycles of mosses, ferns, and conifers include alternation of generations. 2. Flowers are the reproductive structures of anthophytes. 3. In anthophytes, seeds and fruits can develop from flowers after fertilization. I. Reproduction in Plants A. Asexual reproduction 1. veg ...
National Human Genome Research Institute
National Human Genome Research Institute

... Changes in the number or structure of chromosomes in new cells may lead to serious problems. For example, in humans, one type of leukemia and some other cancers are caused by defective chromosomes made up of joined pieces of broken chromosomes. It is also crucial that reproductive cells, such as eg ...
Document
Document

... A. In humans XX is female and XY is male 1. The SRY gene has been shown to trigger the development into a male fetus at about 2 months old. 2. SRY probably regulates other genes 3. Some XX male and XY females exist with mutated SRY genes ...
< 1 ... 126 127 128 129 130 131 132 133 134 ... 431 >

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.
  • studyres.com © 2026
  • DMCA
  • Privacy
  • Terms
  • Report