Unit 3 Medical Interventions

Who formed the foundational work on genetics?

Gregor Mendel

What did Mendel’s experiment show?

How dominant and recessive traits ared passed.

What did Mendel’s P1 generation show?

Pure-breeding plants were crossed only yellow or only green

What happened when Mendel crossed yellow and green peas?

Shows that yellow is dominant over green

What is Mendel’s Law of Segregation?

during the formation of gametes (sperm and egg cells), the two alleles for a specific trait separate, or "segregate," so that each gamete receives only one allele.

What is a punnett square?

a chart used in genetics to determine the possible genotypes and probabilities of an offspring from a specific cross between two parents.

How are punnett squares used in biotechnology?

to predict the probability of offspring inheriting specific traits by showing all possible gene combinations from parents.

What is the Law of Independent Assortment?

a principle of genetics stating that the alleles for different traits separate independently of one another during the formation of gametes

Why is the Law of Independent Assortment important in biotechnology?

it is fundamental to genetic variation, allowing for the creation of diverse combinations of traits in offspring

What is a testcross?

a genetic cross where an individual with an unknown genotype (but a dominant phenotype) is crossed with an individual that is homozygous recessive for the trait of interest.

What is homozygous?

having two identical alleles of a particular gene or genes.

What is heterozygous?

having two different alleles of a particular gene or genes.

Why are test crosses important in biotechnology?

they help determine the genotype of an individual with a dominant trait

What is incomplete dominance?

a genetic trait where one allele is not completely dominant over another, resulting in a blended, intermediate phenotype in the heterozygote

What does incomplete dominance show in biotechnology?

a heterozygous genotype can produce an intermediate phenotype

What is codominance?

a genetic trait where both alleles for a gene are fully and equally expressed at the same time in the offspring

What is an example of a trait determined by codominance?

human blood type AB

Why is codominance important in biotechnology?

it allows for the creation of genetic markers

What is polygenic inheritance?

a pattern where a single trait is influenced by the combined effects of multiple genes, resulting in a continuous range of phenotypes rather than distinct categories

What is a classic example of polygenic inheritance produce?

Human skin color

How is sex determined?

primarily based on the presence or absence of the Y chromosome

Why is sex determination important in biotechnology?

for developing species-specific applications

What is a classic example of polygenic inheritance?

human height

How are sex linked traits determined?

by genes located on the sex chromosomes, primarily the X chromosome because it is larger and contains more genes than the Y chromosome

Why are males more likely to express X-linked disorders?

they only have one X chromosome

How do females express sex linked disorders?

a female can be a carrier

Why is it important to understand sex-linked inheritance in biotechnology?

accurately diagnosing and treating genetic disorders, developing targeted therapies, and informing genetic counseling and family planning decisions.

What are chromosomal alterations?

changes in the number or structure of chromosomes, which can result in missing, extra, or rearranged genetic material

What is deletion?

the loss of a segment of DNA, which can range from a single base to an entire chromosome, leading to the absence of one or more genes

What is inversion?

a chromosomal defect where a segment of a chromosome breaks off, flips 180 degrees, and reattaches in the reverse order

What is translocation?

the movement of something from one place to another.

What is duplication?

the action or process of duplicating something.

What is crossing over?

the exchange of genetic material between homologous chromosomes that occurs during meiosis, the process of creating sperm and egg cells.

Why is crossing over important in science and biotechnology?

it is a fundamental source of genetic diversity through the exchange of genetic material between homologous chromosomes during meiosis

When does crossing over occur?

prophase I of meiosis

What is nondisjunction?

the failure of chromosomes or sister chromatids to separate properly during cell division (mitosis or meiosis)

What is the result of nondisjunction?

a gamete with an abnormal number of chromosomes

What disease does nondisjunction help explain?

Down syndrome (Trisomy 21), but also Edwards syndrome (Trisomy 18), Patau syndrome (Trisomy 13), Turner syndrome, and Klinefelter syndrome

What is Down’s syndrome?

a genetic disorder caused by an extra copy of chromosome 21. 

Causes

What is Turner syndrome?

a genetic disorder that affects females, typically caused by the absence or partial deletion of one X chromosome. 

What is Klinefelter syndrome?

a genetic disorder that affects males, caused by an extra X chromosome.