Lampbrush chromosomes (LBCs) are giant meiotic chromosomes first described more than 100 years ago from the oocyte nucleus or germinal vesicle (GV) of the axolotl (Flemming 1882) and a shark (Rückert 1892).
Who discovered Lampbrush chromosomes?
Lampbrush chromosomes were discovered in sala- mander egg cells (Ambystoma mexicanum) by Flemming in 1882. Ten years later, LBCs were identified in shark egg cells and described by Rückert in 1982. It was Rück- ert who introduced the term “lampbrush chromosome” into biological nomenclature.
Do humans have Lampbrush chromosomes?
Human and other mammalian chromosomes do not form recognizable lampbrush chromosomes in their own oocytes or in any somatic cells.
What are Balbiani rings?
Balbiani rings are exceptionally large puffs on the polytene chromosomes in the dipteran Chironomus tentans. These puffs are particularly well suited for studies of the structure of active genes and the synthesis and transport of specific RNA-protein (RNP) particles.
Can a woman have Y chromosome?
Each person normally has one pair of sex chromosomes in each cell. The Y chromosome is present in males, who have one X and one Y chromosome, while females have two X chromosomes.
Which is the largest chromosome?
Chromosome 1 is the largest human chromosome, spanning about 249 million DNA building blocks (base pairs) and representing approximately 8 percent of the total DNA in cells.
What is the meaning of Chromomere?
: one of the small bead-shaped and heavily staining masses of coiled chromatin that are linearly arranged along the chromosome.
What are types of chromosomes?
There are four main types of chromosomes: metacentric, submetacentric, acrocentric, and telocentric. Chromosomes are found within the nucleus of most living cells and consist of DNA that is tightly wound into thread-like structures.