unit 7 - genetics

Question 1

allele

Answer 1

alternative form that a single gene can have for a particular trait

Question 2

autosome

Answer 2

chromosome that is not a sex chromosome

Question 3

carrier

Answer 3

individual that is heterozygous for a recessive disorder, and expresses the dominant pheotype.

Question 4

chromosome

Answer 4

condensed DNA contaning structure that carries genetic material thru generations

Question 5

codominance

Answer 5

non-mendelian pattern of inheritance that occurs when more than one allele is dominant and are equally expressed

Question 6

crossing-over

Answer 6

exchange of chromosomal segments between a pair of homologous chromosomes during prophase I of meiosis

Question 7

dihybrid cross

Answer 7

cross of two individuals differing in 2 traits

Question 8

diploid

Answer 8

• 2 copies of each chromosome
• (2n)
• body/somatic cells

Question 9

dominance

Answer 9

relation between alleles in which the phenotype of one allele masks the phenotype of the other allele.

Question 10

dominant trait

Answer 10

mendels name for a specefic trait that appeared in the F1 generation
- is expressed & has the ability to hide/mask the recessive form.

Question 11

F1(filial) generation

Answer 11

first generation of offspring produced by a set of parents

Question 12

fertilization

Answer 12

process where a haploid sperm fuses with a haploid egg/ovum to become a diploid zygote (fertilized egg)

Question 13

gamete

Answer 13

• haploid sex cell
• formed from meiosis

Question 14

gene

Answer 14

functional unit of DNA that controls inherited trait expression that is passed thru generations

Question 15

genome

Answer 15

entire set of DNA found in nucleus of each cell in organism

Question 16

genotype

Answer 16

orgenism’s allele pairs are represented by letters
- capital (dominant)
- lowercase (recessive)

Question 17

haploid

Answer 17

one copy of each chromosome
- half of diploid
- gametes/sex cells

Question 18

heterozygous

Answer 18

organisms with 2 diff alleles for a specific trait

Question 19

homologous

Answer 19

• paired chromosomes
• one from each parent
• location of centromere anc carry genes for the same traits at the same location
• similar not identical

Question 20

homozygous

Answer 20

organisms with 2 of the same forms of allles for a specific trait (pubread)

Question 21

incomplete dominance

Answer 21

non mendelian in heritance patter
- heterozygous have 2 diff alleles where neither is dominant over the other
- phenotype of intermediate and a blend b/w the two homozygous parent organisms.

Question 22

inherited trait

Answer 22

traited passed from parent to offspring, determined by genes

Question 23

law of independent assortment

Answer 23

mendelian law stating that a random distribution of alleles found on diff chromosomes occurs during the formation of gametes

Question 24

law of segregation

Answer 24

mendelian law states that 2 alleles for each trait seperate during meiosis

Question 25

monohybrid cross

Answer 25

repro process that only occurs in diploid, gametes
- 1 diploid produces 4 haploid cells & each are genetically unique

Question 26

monohybrid cross

Answer 26

cross of 2 indivduals differing in 1 trait

Question 27

multiple alleles

Answer 27

having more than 2 alleles for a trait in a population (ex - blood types)

Question 28

non-mendelian inheritance

Answer 28

inheritance of traits having more complex patterns that complete dominant and recessive relations b/w alleles

Question 29

pedigree

Answer 29

diagrammed fam history that is used to study inheritance patterns of a trait thru several generations

Question 30

phenotype

Answer 30

observable characteristic that is physically expressed as a result of an allele pair

Question 31

punnett square

Answer 31

square diagram thats used to predict the ofspring genotypes of a particular cross/breeding expiriment

Question 32

recessive

Answer 32

mendel’s name for a trait hidden or masked by a dominant allele

Question 33

sex cell

Answer 33

haploid repro cells of an organism that are the product of meiosis

Question 34

sex chromosome

Answer 34

X/Y chromosomes
- paired sex chromosomes determine the genetic sex of an individual (XX female, XY male)

Question 35

sex-linked trait

Answer 35

characteristic/trait controlled by genes on the X chromosome (x-linked trait)

Question 36

tetrad

Answer 36

a 4 part structure that forms during prophase I of meiosis
- consists of 2 homologous chromosomes, each composed of 2 sis chromatids, crossing over may occur

Question 37

zygote

Answer 37

fertilized egg
cell formed by union of 2 gametes