Unit 8-A Flashcards
(50 cards)
1
Q
Gene definition
A
Segments of DNA on a chromosome that code for a trait.
2
Q
Alleles?
EXAMPLE?
A
- The different forms of a gene.
- Ex. Green pea pod allele or yellow pea pod allele
3
Q
The Principle of Dominance
A
- Some alleles are dominant + others are recessive.
4
Q
The Principle of Segregation
A
- Each gamete will only receive 1 copy of a gene in meiosis.
5
Q
The Principle of Independent Assortment
A
- Each gene is inherited separately from others if they’re on different chromosomes
6
Q
Dominant
A
- An allele (gene) that masks another.
- Predicts inheritance with a capital letter.
7
Q
Recessive
A
- An allele (gene) that’s not observed when the dominant gene’s present
- Predicts inheritance with lowercase letter
8
Q
What’s each trait determined by?
A
- Each trait is determined by 2 GENES (1 from EACH PARENT).
9
Q
Genotype
A
- The gene combo for a trait
- Ex. RR, Rr, rr
10
Q
Homozygous genotype (PURE)
A
- Gene combo involving 2 dominant/ 2 recessive genes. (Gene pair is the same)
- Ex. RR, rr
11
Q
Heterozygous genotype (HYBRID)
A
- Gene combo of 1 dominant + 1 recessive allele. (Gene pair is different)
- Ex. Rr
12
Q
Phenotype
A
- The physical appearance that results from the gene pair.
- Ex. Plant = green/yellow
13
Q
Punnett Square
A
- Tool used to calculate genetic outcomes
14
Q
Monohybrid Cross
A
- A genetic cross that compares only 1 trait
- Ex. Flower color
15
Q
Dihybrid Cross
A
- A genetic cross that compares 2 different traits
- Ex. Flower color + plant height
16
Q
Test cross
A
- A genetic cross between an unknown genotype and a homozygous recessive
17
Q
Gregor Mendel
A
- An Austrian monk that worked on inheritance using garden peas.
- Father of Genetics
18
Q
Mendel said that ____ ____ were inherited as particles. Particles are…
A
- Physical traits
- Particles are Chromosomes + DNA.
19
Q
2 forms of alleles
A
- Dominant and Recessive
20
Q
2 things that determine an organism’s characteristics?
A
GENES/DNA + ENVIRONMENT determine an organism’s characteristics.
21
Q
How did Mendel get pure plants?
A
- He allowed them to self-pollinate for several generations
22
Q
P1
A
- Parental generation in a breeding experiment.
23
Q
F1 generation
A
- 1st generation offspring in a breeding experiment
24
Q
F2 generation
A
- 2nd generation offspring in a breeding experiment
25
Phenotype is based on ___?
Phenotype is based on GENOTYPE & ENVIRONMENT
26
Incomplete dominance
- Neither allele is dominant or recessive.
- The heterozygous phenotype is a blending of traits.
- Ex. Red + white = pink flowers
27
Codominance
- Both alleles are expressed at the same time.
- The heterozygous phenotype will show both traits at the same time.
- Black + white = black + white feathers
28
Multiple Allele traits
- Traits determined by 2+ alleles.
29
Blood type is determined by...
- Blood type is determined by 3 alleles: I^a, I^b, and i.
| - Multiple Allele trait
30
Polygenic traits
- Traits determined by 1+ gene.
31
Human skin color
- 4+ genes control this trait.
| - Polygenic trait
32
Sex linked traits
- Traits (genes) that are carried on the X or Y sex chromosomes.
- Ex. Hemophilia + color blindness
33
Dominant disease
- Caused by a dominant allele
| - Ex. Huntington's
34
Recessive disease
- Caused by a recessive allele
| - Ex. Cystic Fibrosis
35
How do you find the gametes for a dihybrid cross?
- FOIL
36
Most sex linked traits carried on what chromosome?
X chromosomes
37
Germ cell mutation
- Occurs in sex cells and can be passed on to offspring.
38
Somatic cell mutation
- Occurs in body cells and won't be passed to offspring
39
Antigen
- A cell surface marker protein
| - Proteins on the blood
40
Antibody
- A plasma protein that will attack similar antigens
41
Function of the heart
- Squeezes blood throughout the body in a closed loop.
42
Blood A
- A antigens
- Anti- B antibodies
- Can receive from A+O
- Can give to A and AB
43
Blood B
- B antigens
- Anti-A antibodies
- Can receive from B+O
- Can give to AB+B
44
Blood AB
- A+B Antigens
- No antibodies
- Can receive from all
- Can only give to AB
45
Blood O
- No antigens
- A+B antibodies
- Can receive from O
- Can give to all
46
Monohybrid Heterozygote cross ratios
1. Phenotype ratio: 3:1
| 2. Genotype ratio: 1:2:1
47
Dihybrid Heterozygote cross ratio
1. Phenotype ratio: 9:3:3:1
48
What are mutations caused by?
- Mutations are caused by mutagens like UV light or chemicals
49
Frameshift mutation
- A frame shift mutation occurs if 1+ nucleotides in DNA are added or deleted.
- This causes the codon sequence to be shifted
50
Female vs. Male Genotypes
- Female: XX
| - Male: XY
