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Meiosis
Meiosis

... In your science notebook, READ and take NOTES on the differences between asexual vs. sexual reproduction. Think about how genes (traits) are passed from parent to offspring for each. Also note some examples of each type. ...
B/b
B/b

... The most likely natural cause of polyploidy in plants is the formation of unreduced (2n) gametes in diploid individuals. Some causes of unreduced gamete formation are: ...
Chromosomal Basis of Inheritance
Chromosomal Basis of Inheritance

... Crossing-over can disrupt a blocked allele pattern on a chromosome  Affected by distance between genetic loci  Consider three genes on one chromosome:  If one at one end, a second at the other and the third in the middle  Crossing over very likely to occur between loci  Allelic patterns of gran ...
MULTIPLE ALLELES Characteristics of multiple alleles – Skin colour
MULTIPLE ALLELES Characteristics of multiple alleles – Skin colour

... being wild form & the other mutant.However soon it became know that a gene can have more than two allelomorphs making a series of multiple alleles. It is also possible that several alleles exhibit themselves within the same phenotypic range, whether wild or mutant. Such alleles expressing themselves ...
SCI 30 UA CH 2 Review Questions
SCI 30 UA CH 2 Review Questions

... c. State the probability of a male with hairy ears passing this trait onto his son. ...
WORKSHEET PATTERNS OF HEREDITY
WORKSHEET PATTERNS OF HEREDITY

... For each statement below, write true if the sentence is correct. If the sentence is incorrect, rewrite the sentence to make it right. 6. Traits controlled by more than two genes are said to have multiple alleles. 7. Multiple alleles can be studied only in individuals. 8. In humans there are 23 pairs ...
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General Genetics General concepts Genetic information is

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F. Mutation and Repair 1. Background on DNA Mutations

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lecture-1 - ucsf biochemistry website
lecture-1 - ucsf biochemistry website

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2.5.15 Summary - Intermediate School Biology

... Mitochondria are found in the cytoplasm of every cell. Number of mitochondria per cell varies. Mitochondria contain their own DNA (a small amount- 39 genes). Known as mtDNA Code for some of the enzymes and other materials e.g. RNA required for respiration. Mutations in mtDNA may lead to mitochondria ...
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Mendelian Genetics Study Guide—AP Biology

... Be able to use the laws of probability/multiplication and additive rules (especially to solve complex problems)—Note: Read Section 14.2 in Campbell (pp. 258-259) Incomplete dominance—Concept understanding and ability to work these kinds of problems Codominance—Concept understanding and ability to re ...
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... Genetic Inheritance • A single inherited trait of an individual can be determined by one pair or by many pairs of genes. ...
RELATION BETWEEN HOMOZYGOUS VIABILITY AND
RELATION BETWEEN HOMOZYGOUS VIABILITY AND

... C y O/+ 9 , where Cy 0 denotes Curly wings and complex inversions and the cn bwD chromoand some was selected for high sensitivity to the segregation-distorter (SD) locus (SANDLER HIRAIZUMI1959). The grandparental mating was C y O/S 8 x 9 , and various inbreeding levels were derived i n the last gene ...
Lesson 3
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... Most cells of your body contain a nucleus—the cell’s control center. Inside each nucleus is a set of chromosomes. A chromosome is Most cells in the body contain 46 chromosomes arranged as a threadlike structure 23 pairs. found within the nucleus of a cell that Sections of chromosomes, called genes, ...
biology of myths and monsters
biology of myths and monsters

... sperm and egg cells, must be haploid, one copy of each chromosome, so that when the sperm fertilizes the egg, the diploid condition is restored. The special cell division process to convert a diploid body cell into a haploid gamete is called “meiosis”. During meiosis, the pairs of chromosomes line u ...
Document
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... females (with two X chromosomes) and in males (with one X chromosome) In mammals: only one X chromosome is active in each cell ...
Review for Biology Spring Semester
Review for Biology Spring Semester

... 11. Compare mitosis and meiosis: purpose, number of cell divisions, products… Mitosis is asexual reproduction to help your body replace old cells and heal, there is only one set of division that produces the same amount of chromosomes (Humans=2323) Meiosis is sexual reproduction to make gametes (s ...
Chapter 2: Genes in pedigrees
Chapter 2: Genes in pedigrees

... the   germ   line.     Contrary   to   the   somatic   cells   and   cells   of   the   germ   line,   gametes   only   contain   one   copy   of   the   “genomic   encyclopedia”.     The   number   of   chromosomes   found   in   haplo ...
Initiation of recombination suppression and PAR formation during
Initiation of recombination suppression and PAR formation during

... from the last common Tokudaia ancestor. On the basis of the sequence data for mitochondrial cytochrome b (Cytb) and nuclear recombination activating gene 1 (RAG1), divergence times between T. muenninki and the two other species are estimated to be around 1.5–1.7 and 0.6–0.8 million years ago (MYA) ( ...
View PDF
View PDF

... Figure 6.2 for reference. 1. Draw a cell with four chromosomes in the first box. Make one pair of chromosomes large and the other pair small. Color in one large chromosome and one small chromosome. 2. In the next box, draw the cell in prophase I. Have each pair of homologous chromosomes line up toge ...
Mutations
Mutations

... - Can involve rearranging chromosome structure or changes in the number of chromosomes. - Can be harmful (genetic disorder or death), neutral, or beneficial ...
Genetics
Genetics

... the environment. ...
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Chromosome



A chromosome (chromo- + -some) is a packaged and organized structure containing most of the DNA of a living organism. It is not usually found on its own, but rather is complexed with many structural proteins called histones as well as associated transcription (copying of genetic sequences) factors and several other macromolecules. Two ""sister"" chromatids (half a chromosome) join together at a protein junction called a centromere. Chromosomes are normally visible under a light microscope only when the cell is undergoing mitosis. Even then, the full chromosome containing both joined sister chromatids becomes visible only during a sequence of mitosis known as metaphase (when chromosomes align together, attached to the mitotic spindle and prepare to divide). This DNA and its associated proteins and macromolecules is collectively known as chromatin, which is further packaged along with its associated molecules into a discrete structure called a nucleosome. Chromatin is present in most cells, with a few exceptions - erythrocytes for example. Occurring only in the nucleus of eukaryotic cells, chromatin composes the vast majority of all DNA, except for a small amount inherited maternally which is found in mitochondria. In prokaryotic cells, chromatin occurs free-floating in cytoplasm, as these cells lack organelles and a defined nucleus. The main information-carrying macromolecule is a single piece of coiled double-stranded DNA, containing many genes, regulatory elements and other noncoding DNA. The DNA-bound macromolecules are proteins, which serve to package the DNA and control its functions. Chromosomes vary widely between different organisms. Some species such as certain bacteria also contain plasmids or other extrachromosomal DNA. These are circular structures in the cytoplasm which contain cellular DNA and play a role in horizontal gene transfer.Compaction of the duplicated chromosomes during cell division (mitosis or meiosis) results either in a four-arm structure (pictured to the right) if the centromere is located in the middle of the chromosome or a two-arm structure if the centromere is located near one of the ends. Chromosomal recombination during meiosis and subsequent sexual reproduction plays a vital role in genetic diversity. If these structures are manipulated incorrectly, through processes known as chromosomal instability and translocation, the cell may undergo mitotic catastrophe and die, or it may unexpectedly evade apoptosis leading to the progression of cancer.In prokaryotes (see nucleoids) and viruses, the DNA is often densely packed and organized. In the case of archaea by homologs to eukaryotic histones, in the case of bacteria by histone-like proteins. Small circular genomes called plasmids are often found in bacteria and also in mitochondria and chloroplasts, reflecting their bacterial origins.
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