Chromosome number, precise number of chromosomes typical for a given species. In any given asexually reproducing species, the chromosome number is always the same. In sexually reproducing organisms, the number of chromosomes in the body (somatic) cells typically is diploid (2n; a pair of each chromosome), twice the haploid (1n) number found in the sex cells, or gametes. The haploid number is produced during meiosis. In some sexually reproducing organisms, individuals may be produced from unfertilized eggs and therefore are haploid; an example is a drone (a male bee).
An organism with any multiple of the diploid number of chromosomes is said to be polyploid. Polyploidy is a normal evolutionary strategy among many plant groups but appears to be quite rare in animals. Examples of polyploid plants and animals are the potato (Solanum tuberosum), the African clawed frog (Xenopus laevis), and the plains viscacha rat (Tympanoctomys barrerae; also called red vizcacha rat). In most animals, however, any change from the typical chromosome number for a species may be accompanied by changes—sometimes drastic—in the organism. For instance, in humans, fetuses affected by polyploidy often are spontaneously aborted early in pregnancy.
The number of chromosomes does not correlate with the apparent complexity of an animal or a plant: in humans, for example, the diploid number is 2n = 46 (that is, 23 pairs), compared with 2n = 78, or 39 pairs, in the dog and 2n = 36 (18) in the common earthworm. There is an equally great range of numbers among plants.
#Chromosome #2n #1n #chromosomeNumber #diploid #haploid #Dna #Genome #allele #somatic #egg #sperm #geneticsClass12 #GeneticsLecture #geneticsBiology #geneticsCrashCourse #geneticsAndHeredity
1 view
16
2
6 years ago 00:09:00 20
Сравнение хоккейных коньков Bauer Nexus 2N 1N
2 years ago 00:03:18 0
2N, 1N, N | Diploid, Haploid | Chromosome number
2 years ago 00:14:49 45
Как найти сумму ряда ∑ n∙ln((2n+1)/(2n−1))−1? // Сергей Фролов / Математический мирок
2 years ago 00:02:43 3
Seymour Duncan SH-2N (Jazz) vs ’59 SH-1N
5 years ago 00:04:20 0
「1N’ 2N’ ONE N’ ONLY!! ~Special Live~」ONLINE LIVE DIGEST
4 years ago 00:07:46 0
Уравнение (sinx)^2n + (cosx)^2n = 1
2 years ago 00:03:01 21
Сократите дробь ➜ (36^n+6^(n+1)+8)/(2^(n+1)+12^n) ➜ ОГЭ по математике
4 years ago 00:16:35 0
ONE N’ ONLY TV#18/ONLINE LIVE「1N’ 2N’ ONE N’ ONLY!! ~Special Live~」②
6 years ago 00:08:25 13
100 тренировочных задач #83 1+2x+3x^2+...+(n+1)x^n
2 years ago 00:14:43 24
Предел последовательности с общим членом ((n+1)(n+2)...(2n))^(1/n)/n // Сергей Фролов / Математический мирок
4 years ago 00:04:31 3
ONE N’ ONLY/ “Breathe” ONLINE LIVE 1N’ 2N’ ONE N’ ONLY!! ~Special Live~
12 years ago 00:07:06 69
Rachmaninov - Etudes tableaux n.2 / n.1 - H. Grimaud
13 years ago 00:10:33 40
m^4 - 2n^2 = 1
3 years ago 00:10:02 39
#1 Dirt Rally 2 N’to-Trauma Worakls Remix
3 years ago 00:00:37 0
Реле безопасности PILZ PZA 300/24VDC 1N/O 2N/C 774029 - Олниса
4 years ago 00:17:41 0
ONE N’ ONLY TV#17/ONLINE LIVE「1N’ 2N’ ONE N’ ONLY!! ~Special Live~」① 【BUDDiiS初登場!】
1 year ago 00:13:14 14
Найти произведение косинусов вида cos(𝝅k/(2n+1)), где k от 1 до n // Сергей Фролов / Математический Мирок
4 years ago 00:09:02 18
Задача-ГРОБ от Серпинского! Бесконечность натуральных n|2^n+1. Не угадал ответ — потратил 3 дня...
1 year ago 00:12:55 35
Сумма функционального ряда ∑ 1/2^n · tg(x/2^n) // Сергей Фролов / Математический Мирок