Week 1 Flashcards

A combination of some sections of chapter 14 and 13

Sexual Reproduction

the combination of genetic mater from two parents of which an offspring will receive half of its genetic information from each of its parents (sperm and egg)

Gametes

haploid cells that are created at the end of meiotic cell division (23 chromosomes)

Fertilization

the process in which two gametes from two parents fuse together to form a zygote (diploid cell)

Meiotic Cell Division

A cell division process which produces four haploid daughter cells from a parent cells

These cells are genetically unique from each other

There are two different round of successive cell division with one round of DNA replication

Meiosis 1

The first round of cell division in meiotic cell division which homologous chromosomes separate and there is a reduction in the total number of chromosomes in half

crossing over will occur at this time

Meiosis 2

The second round of cell division in meiotic cell division in which sister chromosome will separate

this process is the most similar to mitosis and the number of chromosomes will remain the same

Cytoplasm Division in Female Mammals

The division of the cytoplasm in female mammals which is unequally divided and forms an octye which is considered an egg cell

Cytoplasm Division in Male Mammals

The division of the cytoplasm in male mammals which is divided equally and produces four sperm cells

Chromosomes Theory of Inheritance

A theory which states that chromosomes are the basis of inheritance and are passed down from a parent to a daughter cell during cell division

Nondisjunction

The failure of a pair of chromosomes to separate during the anaphase portion of cell division

The result is that a daughter cell will receive an extra copy of a chromosomes while another will lack that copy

First Division Nondisjunction

Homologous chromosomes don’t separate accordingly and results extra/missing chromosomes

This occurs during meiosis 1

The result is that 2 haploids will have an extra pair of chromosomes and 2 will have no pairs

Second Division Nondisjunction

Sister chromatids don’t separate accordingly and produce gametes with extra/missing chromosomes

This occurs during meiosis 2

The results is 2 haploids with the correct number of chromosomes, 1 with and extra pair and 1 with a missing chromosome

Dominant

An allele of a gene that is expressed in heterozygotes where only one dominant allele is needed to express the phenotype

Recessive

An allele of a gene that is expressed in heterozygotes where two recessive alleles are needed to express the phenotype

Principle of Segregation

The separation of alleles into different gametes during meiosis in which half of the gametes will receives one allele and the other half will receive another allele

Heterozygous

Two alleles for a given given inherited from each parent that are different

Punnett Square

Shows the frequency of gametes from each parent in a box and shows all possible genotypes of all the possible offspring genotypes

Testcross

Any cross of an unknown genotype with a homozygous recessive genotype which helps reveal the genotype of the other parent (heterozygous or homozygous)

Incomplete Dominance

A phenotype of a heterozygous genotype is intermediate between those of homozygous genotypes

Ratio is 1:2:1 as theres is a distinct phenotype for each genotype

Codominance

Describes how both alleles are able to produce a characteristic phenotype that is shown in heterozygous genotypes

ex. type AB blood type

Addition Rule

A process used when possible outcome cant occur simultaneously; shows that the chances of either occurring is given by the sum of their individual probabilities

Multiplication Rule

A process used when outcomes can occur simultaneously with no effect on each other; the probability of two independent event occurring together is the product of their respective probabilities

Mutations

Permanent change in DNA sequences that can occurs over time which are necessary for evolution to occurs

Genotype

The genetic makeup of a cell or organism in which there is a large variation

Polymorphism

The genetic differences present amongst individuals in a population

ex. difference base pairs in a certain portion of the genome

Alleles

Different forms of any gene; referring to specifically different DNA sequences in the genes

Phenotype

Gene Expression, an individuals observable characteristics or traits or can be behavior or development of cells or the organism

Harmful Mutations

These mutations are often eliminated in early generations since these types of mutations decrease survival and reproduction

Neutral Mutations

Mutations that will not affect the survival or reproduction rate

Beneficial Mutations

Mutations that will improve the chance of survival and reproduction

Mutation Effects

Effects of a mutation depends on factors such as the presences of certain genes and environment