Chapter 13 Pt 1 Flashcards
Heredity
Transmission of traits from one generation to the next
Genetics
Scientific study of heredity and heredity variation
What does ploidy refer to?
The number of chromosome sets an organism carries
Haploid
Cells contain only one set of chromosomes
n=23
Diploid
- Most multicellular eukaryotes
- two sets of chromosomes
- 2n=46
What does it mean for two chromosomes to be homologous?
Carry the same set of genes and look the same
-usually don’t have the exact same genetic information (different alleles)
Alleles
Different versions of the same gene
Locus
Where a gene is located on a chromosomes
Karyotype
A display of the chromosome pairs of a cell arranged by size and shape
Autosomes
All of the other chromosomes (besides the sex chromosome)
How is sex determined in humans?
Y-chromosome
- SRY region= sex determining region Y
- in the absence of a functional SRY gene, an embryo will develop as a female
X and Y chromosomes
- Look different from one another
- Have different genes on them
- y is much smaller than x; carries fewer genes
Asexual reproduction
One parent gives rise to offspring
- no fusion of gametes
- offspring and parent are genetically identical
Budding
Hydra
Sexual reproduction
Gives rise to offspring; each contribute a gamete
- meiosis produces the haploid gametes for sexual reproduction
- offsprings are genetically unique; each have a unique combination of genes from the two parents
