General Bio I- Final Exam: Genotype - Genetic variation

Genotype

The genetic makeup of an individual organism

phenotype

The observable characteristics of an organism *physical traits)

homozygous

When there are 2 identical alleles (RR rr)

heterozygous

When there are 2 different alleles (Rr)

dominate alleles

a version of a gene whose traits are expressed even when only 1 copy is present in n individuals genotype. has enough functional protein for full trait

recessive alleles

when there are 2 different alleles causing 1 to be present

when is a recessive trait expressed?

Recessive trait can only be expressed when the genotype is homozygous recessive

complete dominance

One allele is full dominated; the heterozygote shows the same phenotype as the homozygous dominate individual

incomplete dominance

Neither of the alleles are dominate making the zygote show a blend of both phenotype

codominance

Mode of inheritance share 2 alleles are fully expressed heterozygote. AB as both a and b have to be present

ABO blood system

The alleles that determine one’s blood type based on the presence and absence of A and B antigens.

Haploid

2 sets of chromosomes (gametes)

Diploid

two sets of chromosomes (body cells)

sex determination

Is determined by sperm (xx female xy male) eggs always carry x chromosome and sperm can carry either or

sperm

has the power of picking biological sex and has x or y chromosomes

sex linked traits

Since males only have 1 x chromosome, they are more likely to develop linked disorders. females have 2 X chromosome one is heathy and enough to prevent diseases. (internal bleeding, muscle hemorrhages, prolong bleeding, spontaneous bleeding)

Hemophilia

an x linked recessive disorder caused by a defective blood clotting protein gene.

cystic fibrosis

An autosomal recessive disease when one inherits 2 mutated copies of the CFTR gene (1 from each parent)

CTFR gene

encodes a protein that functions and chloride and bicarbonate ions to regulate salt and water transport. Maintains organ tissues hydrated with thin free flowing mucus

Females

can be carriers of genes even if they do not have the disease

Mutated CTFR gene

The mutation stops the movement of chloride stopping water flow creating a thick and sticky mucus

Pleiotropy

a single gene influence multiple seemingly unrelated traits or body systems caused by a dominate mutation. bell shaped curve

Marfan syndrome

When a defective allele becomes dominate and causes the disorder. This effects heart, blood vessels eyes, bones, and joints (long limbs, think fingers)

single gene traits

controlled by one gene and its allele (cystic fibrosis, sickle cell)

polygenic traits

are influenced by combining effects of multiple genes with environmental contributing (height, skin, color, weight)

flower color

color is influenced by acidic ph in soil. aluminum becomes available and changes the pigment creating blue flowers. without aluminum creates pink or purple

different allele combinations

causes genetic variation due to mutations, recombination, and environmental factors.

why is genetic variation important?

genetic variation helps people, adapt and survive changes