Chromosomes and Genes Flashcards
how did Walter Fleming discover chromosomes
using red dye to stain embryos, he saw red threadlike material that doubled during cell division
what was Thomas Hunt Morgan’s theory when he bred flies
that chromosomes carry genes
what do genes determine
inherited characteristics
genes definition
functional units of dna (they code proteins)
what’s nucleosome
compacted DNA knotted together
what are chromosome pairs called
homologous pairs
what don’t have chms
what do they have instead
bacteria
circular pieces of DNA instead
how many chms do humans have
how many pairs
46
23 pairs
what’s composed of DNA wrapped around histones
chromatin
where are chromatids joined in the chm structure
centromere
what’s the end/tip of chromatids known as
telomere
What does fluorescent in situ hybridisation (FISH) consist of
paint chms with fluorescent probe
denature chms and hybridise with fluorescent probe
results in fluorescent stain
what does FISH make easier
to detect deletions and translocations among chromosomes
how many copies of every chm
where from
2
1 from mother, 1 from father
what are the sex chromosomes named
what number pair are they
X and Y
23
what’s diploid number
total number of chms
what’s haploid number
half total number of chms (one of each pair)
where’s haploid number only found
in gametes
what are chm pairs 1-22 called
autosomes
what makes male
1 X and 1 Y
what makes female
2 X’s
