Benchmark Flashcards
Meiosis is a process that makes what kind of cells?
Sex cells AKA Gametes.
Where do Sex cells come from?
Germ Cells.
Sex Cells are also called..?
Gametes
How many chromosomes do gametes have in the average human?
23 Chromosomes.
Body cells are also called…?
Somatic Cells.
In humans somatic cells have __ Chromosomes.
46 chromosomes.
How does meiosis increase genetic Variation?
Crossing over and independent Assortment.
Occurs during Prophase 1 and provides almost infinite combinations of genes on chromosomes.
Crossing Over.
Occurs in Metaphase 1 and provides over 8 billion comibinations of chromosomes.
Independent Assortment.
Meiosis produces gametes. These gametes… Are Which of the following
A.) Haploid
B.) Diploid
A.) Haploid.
Meiosis produces gametes. These gametes…Are which of the following.
A.) Have 23 chromosomes
B.) Have 46 chromosomes
A.) Have 23 Chromosomes.
Meiosis produces gametes. These gametes…Are which of the following.
A.) Are genetically identical
B.) Different.
B.) Different.
What is is the name of the new cell that is made from fertilization?
A zygote is made.
1 sperm (n)+1 egg (n) = Zygote (2n
Why do you look like your parents?
Because of the traits you inherit.
What is an allele?
A form of a gene that determines traits, represented by upper/lower case letters.
Homologous chromosomes have the same____, but possible different _____.
Genes
Alleles.
What is the difference between a homozygous and heterozygous genotype?
Homozygous means the genotypes are the same Ex: RR, rr
Heterozygous means the genotypes are different Ex: Rr
is Purebred another word for…
A.) Homozygous
B.) Heterozygous
A.)Homozygous
Hybrid is another word for…
A.) Homozygous
B.) Heterozygous
B.) Heterozygous
The alleles that are inherited
Genotype.
Physical trait, what the organism looks like.
Phenotype.
Allele that is always expressed when it is present, represented by an upper case letter.
Dominant.
Allele that is only expressed when 2 recessive alleles are present.
Recessive.
Organisms only donate 1 cope of each gene in their gametes.
Law of segregation.
In a cross of parents that are homozygous for different traits only the dominant phenotype will appear in the next generation.
Law of Dominance.
During meiosis, chromosome pairs line up independently of each other, so different alleles are distributed to sex cells independently of one another.
Law of Independent assortment.
Probabilities do not predict the _____ results, but they can predict the ______ number of occurrences.
Exact, Average.
A family has 5 male children. What are the chances of the mother having a girl for her next child? Why?
50% no matter how many children she may have the probability will stay the same.
If a gene comes in more than 2 forms it is an example of what?
Polygenic traits.
The first 22 pairs of chromosomes in a karyotype are called ______, the 23rd pair are called ____ chromosomes.
Autosomes, sex.
dna is different in every person except for who?
Identical twins.
Involve the loss of part of a chromosome.
Deletion.
Reverse the direction of parts of chromosomes.
Inversion.
Produce extra copies of a chromosome.
Duplication.
Occurs when part of a chromosome breaks off and attaches to another chromosome.
Translocation.
There are ____ chromosomes in each normal human gamete.
46
what type of cells does nondisjunction affect?
Sex cells/gametes.
Most sex linked traits are carried on the ___ chromosome.
X
What sex chromosome is found in an egg cell in a female?
X
What is recombinant DNA?
DNA that contains genes from more than one organism.
Genetic engineering can alter the ___ of an organism.
DNA
