Genetics Flashcards
Male part of a plant that creates pollen (plant sperm) {stamen}
Long tubes
Anther
Ovary in plants
Holds and releases seeds (plant eggs)
Middle part
Check plant structure diagram
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What is pollen
Plant sperm
Stigma
Sticky pollen trap
Holds and releases seeds (plant eggs)
Middle part
Ovary in plants
Anther
Male part of a plant that creates pollen (plant sperm) {stamen}
Long tubes
Seed needs moisture, temperatures, and some soil nutrients
Germination
Monohybrid crosses
Crossing that involves a one trait difference
Why have colorful flowers and give off sweet smells?
Attract pollinators
Germination
Seed needs moisture, temperatures, and some soil nutrients
Crossing that involves a one trait difference
Monohybrid crosses
True breeding
Offspring only displays one form of the trait being tested
Offspring only displays one form of the trait being tested
True breeding
Inheritance
For each character/trait there are two copies of the gene (one from each parent)
For each character/trait there are two copies of the gene (one from each parent)
Inheritance
Different versions of the gene
Alleles
Dominant traits
If two different alleles are present, the trait that is expressed is the dominant trait
Capital letter
Sticky pollen trap
Stigma
If two different alleles are present, the trait that is expressed is the dominant trait
Capital letter
Dominant trait
Recessive trait
Trait not expressed when dominant form is present
Lowercase
Trait not expressed when dominant form is present
Lowercase
Recessive trait
Could 2 brown eyed parents have a blue eyed baby?
Yes, if both parents are heterozygous Bb
Alleles of different genes separate independently of one another
Ex pea color and pea shape
Law of independent assortment
Could 2 blue eyed parents have a brown eyed baby
No , you can only be homozygous recessive (bb)
Genotype
Set of alleles an individual has
Bb BB bb
Set of alleles an individual has
Bb BB bb
Genotype
Traits that are carried on the X or Y chromosome (mainly on X)
Sex linked traits
Two copies of the same gene
PP
pp
Homozygous
DIFFERENT genes of a trait
Pp
Dominant trait will be observable if an individual is heterozygous
Heterozygous
Alleles
Different versions of the gene
Observable characteristics (what you look like)
Phenotype
Law of segregation
Alleles separate when gametes are formed during meiosis
If segregation fails in humans —> extra chromosomes cause different disorders or non viable fetus
Alleles separate when gametes are formed during meiosis
If segregation fails in humans —> extra chromosomes cause different disorders or non viable fetus
Law of segregation
Amniocentesis
Needle is used to remove amniotic fluid that surrounds fetus
Needle is used to remove amniotic fluid that surrounds fetus
Amniocentesis
Down syndrome
Extra 21st chromosome
Extra 21st chromosome
Down syndrome
Linked traits
Traits that are inherited together because they are close to each other on the same chromosome
Violates the law of independent assortment
Red hair and freckles
Law of independent assortment
Alleles of different genes separate independently of one another
Ex pea color and pea shape
Traits that are inherited together because they are close to each other on the same chromosome
Violates the law of independent assortment
Red hair and freckles
Linked traits
Corn seedlings grown in the dark appear white. After being exposed to sunlight, the same seedlings turn green. The whiteness of these seedlings was most probably due to…
The environment
Sex linked traits
Traits that are carried on the X or Y chromosome (mainly on X)
Test cross
Cross the unknown with a homozygous recessive because if the organism shows the recessive trait it must be homozygous
Unknown dominant X Known homozygous
phenotype (BB or Bb) recessive (bb)
Homozygous
Two copies of the same gene
PP
pp
Heterozygous
DIFFERENT genes of a trait
Pp
Dominant trait will be observable if an individual is heterozygous
Cross the unknown with a homozygous recessive because if the organism shows the recessive trait it must be homozygous
Unknown dominant X Known homozygous
phenotype (BB or Bb) recessive (bb)
Test cross
Polygenic inheritance
Traits influenced by more than one gene
Difficult to determine exact outcomes with these traits
Eye color, skin color
Traits influenced by more than one gene
Difficult to determine exact outcomes with these traits
Eye color, skin color
Polygenic inheritance
Incomplete dominance
Phenotype is an intermediate between the two parents.
Ex- wavy hair by straight hair and curly haired parents
Phenotype is an intermediate between the two parents.
Ex- wavy hair by straight hair and curly haired parents
Incomplete dominance
The individual with the condition will have at least one parent with the condition
Autosomal dominant
See pedigree symbols
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Blood type alleles
I^a I^b i
i allele
Blood type O
Blood type A
I^a
Blood type B
I^b
I^b
Blood type B
Blood type O
i allele
Is blood type A or B dominant
None they are codominant
Could a mother that is type a and a father that is type b have a type o baby
Yes
Dad I^b i
Mom I^a i
What can affect traits
Environment
Ph
Pedigrees
Family history that shows how a trait is inherited over several generations
Family history that shows how a trait is inherited over several generations
Pedigrees
Phenotype
Observable characteristics (what you look like)
Autosomal dominant
The individual with the condition will have at least one parent with the condition
I^a
Blood type A
Autosomal recessive
Individual can have two parents that are not affected, but they must then be heterozygous for the trait
Individual can have two parents that are not affected, but they must then be heterozygous for the trait
Autosomal recessive
Check a pedigree
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Sickle cell anemia
Recessive trait
Poor blood circulation because mutated produces defective hemoglobin and red blood cells are sickle shaped
Recessive trait
Poor blood circulation because mutated produces defective hemoglobin and red blood cells are sickle shaped
Common in African ancestors
Sickle cell anemia
Heterozygous sickle cell anemia
Provides advantage from malaria
Sickle cell individuals have both normal red blood cells and sickle cells. Cause the death of malaria
Hemophilia
Sex linked recessive trait
Blood fails to clot and small cuts can be deadly
Sex linked recessive trait
Blood fails to clot and small cuts can be deadly
Hemophilia
Provides advantage from malaria
Sickle cell individuals have both normal red blood cells and sickle cells. Cause the death of malaria
Heterozygous sickle cell anemia
Autosomal recessive
Individual can have two parents that are not affected, but they must then be heterozygous for the trait
Check a pedigree
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Autosomal recessive
Individual can have two parents that are not affected, but they must then be heterozygous for the trait
Individual can have two parents that are not affected, but they must then be heterozygous for the trait
Autosomal recessive
Autosomal recessive
Individual can have two parents that are not affected, but they must then be heterozygous for the trait
Check a pedigree
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