Genetics Unit Quiz Flashcards
Distinguish mitosis and meiosis.
Mitosis is asexual reproduction, is when offspring are produced by 1 parent through binary fission, therefore it is genetically identical
Meiosis is sexual reproduction and is also referred to as reduction division. It occurs in the germ cells of the gonads. Daughter cells contain half the chromosomes as parent cells (23)
Distinguish between a gene and allele.
A gene is the instructions for each trait found in chromosomes, they are arranged in a specific order on each chromosome
A allele is a singular trait of a gene that controls each trait.
Ex. Floppy ears in dogs is controlled by a gene that has two possible forms (alleles)
B bent ears
b erect ears
Distinguish dominent and recessive.
A dominent allele is the expressed allele, it is represented with a capital letter.
A masked allele is called recessive.
The dominent allele will be the trait that is expressed if a gene is heterozygous.
Distinguash homozygous and heterozygous.
Homozygous is when both alleles are the same. It can be homozygous recessive or homozygous dominent.
Heterozygous is when the two alleles are different and the dominent allele is expressed.
Distinguish phenotype and genotype.
Genotypes are different allele combinations.
Phenotypes is the trait that is expressed.
Distinguish between Somatic cell and sex cells.
Somatic cells have a diploid number of chromosomes, which is 46 chromosomes, while sex cells have a haploid number of chromosomes, which is a total of 23 chromosomes.
Somatic cells are all body cells besides sex cells.
Distinguish autosomes and sex chromosomes.
Autosomes are the first 44 chromosomes in humans. Sex chromosomes are the last 2 chromosomes that determine the gender of humans.
Distinguish between DNA and RNA.
DNA is double stranded and stays in the nucleus DNA is formed from deoxyribose. RNA is a transcription of DNA that is composed of ribose.
Distinguish between nucleotide and amino acid.
A nucleotide is made out of sugar, nitrogen base and phosphate and is the base nucleic acids (DNA) (RNA).
Amino acids compose protein, different amino acid formations determine types of proteins.
Distinguish between Transcription and translation.
Transcription takes place in the nucleus. It is used to make DNA into RNA. At the end of transcription the RNA exits the nucleus and goes into the cytoplasm and translation stage where amino acids are used to from a sequence and proteins are formed.
Distinguish a codon and anticodon.
A codon is a three-nucleotide or triplet sequence found on mRNA that codes for a certain amino acid during translation. The anticodon is a three-nucleotide sequence found on tRNA that binds to the corresponding mRNA sequence. The amino acid transported by the tRNA molecule is determined by the anticodon sequence.
Why is meiosis referred to as reduction division. What event is responsible for reducing chromosome number. How many daughter cells are formed?
It is referred to reduction division due to its result of 23 chromosomes for each of the 4 daughter cells in the final stage. Meiosis 1 is responsible for reducing chromosome number. 4 daughter cells are formed.
List Mendels three laws.
-Law of dominance
-law of segregation (hom/het)
-law of independent assortment (foil)
What is the term crossing over and what effects does it have on genetic variation.
Crossing over occurs in meiosis 1 when chromosome homologous pairs intertwine, break and exchange genetic info which results in more genetic variation.
Look at pedigree
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