Heredity Flashcards
What is a genotype?
The genetic makeup of an organism.
What is meiosis?
Cell division that produces haploid cells, each with ½ of the chromosomes.
What are alleles?
Forms of a gene that can result from mutations.
What is a phenotype?
The observable characteristics of an organism.
What does heterozygous mean?
Having one of each allele.
What does homozygous dominant mean?
Having two dominant alleles (e.g., AA).
What does homozygous recessive mean?
Having two recessive alleles (e.g., aa).
Why is meiosis important?
It is essential for reproduction and genetic variation.
What is gametogenesis?
The formation of gametes through cell growth and fertilization.
What is spermatogenesis?
The formation of sperm.
What is oogenesis?
The formation of eggs.
What is simple complete dominance?
When one allele is dominant over the other (e.g., A = small, a = big, Aa = small).
What is incomplete dominance?
Neither allele is dominant over the other.
What is codominance?
Both alleles are expressed (e.g., blood type A from dad + blood type B from mom = AB).
What is multiple allele dominance?
When there are more than two alleles in a gene (e.g., ABO blood type).
What is polygenic inheritance?
When traits are controlled by multiple genes (e.g., red hair).
What is Mendelian dominance?
A classic pattern where traits are controlled by a gene with two alleles.
What is non-Mendelian dominance?
Patterns that do not follow classic Mendelian inheritance, including sex-linked traits.
What are sex chromosomes?
Chromosomes that determine the sex of the offspring (e.g., X and Y).
What does ‘Homo’ signify in genetics?
Same - represented as BB or bb.
What does ‘Hetero’ signify in genetics?
Different - represented as Bb.
What are the two types of gametogenesis?
Spermatogenesis and oogenesis.
What are the female reproductive structures in plants?
Pistil, which includes stigma, style, and ovules.
What are the male reproductive structures in plants?
Stamen, which includes anther and filament.
What is codominance?
A genetic scenario where two alleles are present and expressed.
What is incomplete dominance?
A genetic scenario where the phenotype is a mix or blend, with a heterozygous genotype.
What are multiple alleles?
More than two alleles for a gene.
What is a sex-linked trait?
A trait associated with a gene that is carried only by the male or female parent.
What is epistasis?
A situation where one gene affects the expression of another gene.
What is polygenic inheritance?
A trait controlled by multiple genes.
What is Mitosis?
Mitosis is a cell division process that produces 2 identical cells.
What is Meiosis?
Meiosis is a cell division process that produces 4 cells, each with half of the chromosomes of the original cell.
What is the starting and ending point of Mitosis?
Mitosis starts with 1 diploid cell and ends with 2 diploid cells.
What is the starting and ending point of Meiosis?
Meiosis starts with 1 diploid cell and ends with 4 haploid cells.
What is the first step in the process of Meiosis?
Start with 1 chromosome pair from mom and dad. Each chromosome codes for the same thing.
What happens after chromosomes duplicate in Meiosis?
Chromosomes line up and crossing over occurs.
What happens after chromosomes split apart in Meiosis?
Pairs split apart again, and gametes form.
What is the male part of the flower?
The stamen consists of the anther and filament.
Color the stamen RED (anthers) & YELLOW (filament).
What does the anther contain?
The anther is the part of the stamen that contains the pollen.
Color the anthers RED.
What is the function of the filament?
The filament is the thin stalk that supports the anther.
Color the filaments YELLOW.
What are petals?
Petals are modified leaves of the flower, often brightly colored to attract pollinators.
Color the petals PINK.
What is the female part of the flower?
The pistil consists of the stigma, style, and ovary.
Color the pistil (stigma is PURPLE, style is GREEN, & the ovary is ORANGE).
What is the stigma?
The stigma is a sticky structure at the top of the style that collects pollen transferred by pollinators.
Just color the stigma PURPLE.
What is the style?
The style is a long, slender stalk connecting the stigma and the ovary.
Just color the style GREEN.
What does the ovary contain?
The ovary sits at the base of the style and contains ovules, or eggs, that will develop into mature seeds once fertilized.
Color the ovary ORANGE.
What is the flower’s role in angiosperms?
The flower is the reproductive organ of angiosperms - plants that bear flowers and fruits.
What does meiosis create in gametes?
Meiosis creates genetic variation in the gametes as alleles are reshuffled into different combinations.
What are the two processes that create genetic variation during meiosis?
The two processes are crossing over and independent assortment.
How can siblings with the same biological parents appear different?
Siblings can appear very different due to the genetic variation created by meiosis, although there is often a family resemblance.
What is crossing over?
Crossing over is the mutual exchange of pieces of chromosomes (and their genes) between homologous chromosomes.
What is the result of crossing over?
Crossing over results in the recombination of alleles in the gametes.
What is independent assortment?
Independent assortment is the random alignment and distribution of homologous chromosomes to the gametes.
What happens to chromosomes during interphase before meiosis?
Chromosomes replicate during interphase to produce replicated chromosomes with sister chromatids held together at the centromere.
What occurs when replicated chromosomes are paired during the first stage of meiosis?
Non-sister chromatids may become entangled and segments may be exchanged in a process called crossing over.
What is the effect of crossing over on offspring?
Crossing over produces greater variation in the offspring than would otherwise occur.
What are polygenic traits?
Polygenic traits are traits that are controlled by more than one gene, such as height, hair color, eye color, and skin color.
How do polygenic traits differ from Mendelian traits?
Polygenic traits are controlled by multiple genes, while Mendelian traits are controlled by a single gene.
What is polygenic inheritance?
Polygenic inheritance describes the inheritance of traits that are determined by more than one gene.
What are polygenes?
Polygene are the genes that produce specific traits when they are expressed together.
How do polygenic traits differ from Mendelian traits?
Polygenic traits are determined by multiple genes, while Mendelian traits are determined by a single gene.
What type of distribution do polygenic traits tend to have?
Polygenic traits tend to have a bell-shaped distribution in a population.
What is incomplete dominance?
Incomplete dominance is when one allele does not completely dominate another, resulting in a mixture of phenotypes.
What are the three key features used to read chromosomes?
Size, Banding Pattern, Centromere position
Each feature is briefly described in the activity.
What is the description of Metacentric chromosomes?
The centromere lies near the center of the chromosome.
What is the description of Submetacentric chromosomes?
The centromere is off-center so one chromatid is longer than the other. The short arm is p and the long arm is q.
What is the description of Acrocentric chromosomes?
The centromere is very near one end.
What is a centromere?
Areas where two chromatids are joined.
Pro
Forward. Favoring. Before
Poly
Many. Several
Hist
Tissue. Woven
Anti
Against. Opposite
Mut
Change
Non
Not
Mis
Wrong
Sub
Under
Trans
Across
Scribe
Write
Script
Write
Ex
Out of
Gen
Producer
Gene
Orgin
Hetero
Different
Homo
Same
Co
With
Zyg
Joined together
Sis. Osis
Condition
Paed. Ped
Child
Oo. Ov. O
Egg
Cyte
Cell
Sperm
Seed
Pheno
Show
Ous
Full of
Gam
Marriage
Epi
Upon
