Test 2 Hereditary & Environmental Influences Flashcards
(51 cards)
Number of chromosomes in a person
46 total or 23 pairs of chromosomes
23 from each parent
Allele….
Specific portion of chromosome that codes for a specific trait
There are atleast 2 alleles that code for each trait.
Homozygous / Hetrozygous
Define…
Homozygous; when both alleles code for the same thing. EXP 2 Blood type A
Hetrozygous: when alleles code for something different. EXP Blood Type A & B
Blood type
Has Alleles for both A & O
Which blood type will they have…
A - due to it being Dominate
Genotype / Phenotype
Genotype (Alleles)
Phenotype (Physical traits)
The two alleles for a given trait (one from each parent) separate during gamete formation, so each gamete receives only one allele.
This ensures that offspring inherit one allele from each parent.
Law of segregation
Trait: Flower color in pea plants.
Alleles: Purple (P) and white (p).
A plant with genotype Pp (heterozygous) will produce gametes with either P or p.
During fertilization, offspring can inherit any combination of these alleles, leading to genotypes PP, Pp, or pp, and phenotypes of purple or white flowers.
Law of Segregation
Alleles for different genes are distributed to gametes independently of one another, provided the genes are located on different chromosomes or far apart on the same chromosome (not linked).
Law of independent assortment
Traits: Seed shape (round, R vs. wrinkled, r) and seed color (yellow, Y vs. green, y).
A plant with genotype RrYy produces four types of gametes: RY, Ry, rY, ry.
The combination of these gametes during fertilization leads to offspring with a variety of genotype combinations (e.g., RrYY, Rryy, rrYy) and phenotypes.
Law of independent assortment
Imagine you have a bag of red marbles and blue marbles. These marbles represent traits like the color of a flower.
You can only give one marble (one trait) to your friend at a time, either red or blue.
When plants make seeds, they also pass along just one of their two traits (like “purple” or “white”) to each seed.
Law of segregation
Now imagine you have two bags—one with marbles for flower color (red or blue) and one with marbles for seed shape (round or square).
When you give a marble from each bag to your friend, which marble you choose from the first bag doesn’t affect which marble you choose from the second bag.
This means traits like flower color and seed shape are chosen separately and don’t depend on each other.
Law of independent assortment
To solve multiple Genotypes in punit squares describe process.
What is probably of RrYy × RRYy producing RrYy
Solve each genotype separate
Make punnit square for (Rr × RR) and note fraction. Rr = 1/2
Make punnit square for (Yy × Yy) and note fraction. Yy = 1/2
Multiple Fractions Straight across.
1/2 × 1/2 = 1/4
Chromosomes are made of….
Which is made of…
Chromatin
DNA & Protein
____ looks at traits that have been passed on in a family.
Genogram / Pedigree
Basic building block of genes and chromosomes
DNA
The sequence of ____ will determine which amino acids will be assembled
Base pairs - Nucleotide
Segments of DNA that direct production of products necessary for structure or function…
Gene
DNA makes Genes
Genes make Chromosomes
T or F
T
Gametes (Sperm & Egg cells) have how many chromosomal pairs…
23
Autosomal….
Body chromosomes
22 pairs in the body
Describe the make up of Male & Female gametes
XX = Female
XY = Male
Karotype….
Genotype….
Phenotype….
Karyotype: Picture/diagram of all the chromosomes in a person’s cells, arranged in pairs and organized by size, shape, and number
Genotype: Genetic composition
Phenotype: Observable characteristics
Monosomy: missing a chromosome (Only 1)
Compatible with life?
Not often compatible with Life
Exceptions: Turner syndrome
Female is born with only one X chromosome
Symptoms include short stature, delayed puberty, infertility, heart defects, and certain learning disabilities.
Trisomy: Extra chromosome ( 3 )
Increase incidents….
Downs 21, 13 & 18 rare & severe
Increase incidents in AMA
