B16 - chromosomes & genes, cell division, monohybrid inheritance Flashcards
which cell has no nucleus
red blood cells
which cells are haploid
gametes
which cells are diploid
all body cells except gametes & red blood cells
how many chromo. & sets in haploid in humans
n = 23
(n = a set of chromo.)
how many chromo. & sets in diploid in humans
2n = 46
-23 pairs
(n = a set of chromo.)
note: no. chromo. varies depending on organisms
how do you number the human chromo.
-largest pair is 1st
-last pair is 23rd pair (sex chromo.)
how long is DNA in each nucleus
2m
what is 1 chromo. to DNA
-1 chromo. = 1 DNA molecule
note: nucleus - chromosome - gene - allele - DNA - bases
how many bases code 1 amino acid
every 3
define inheritance
transmission of genetic information from generation to generation
eg. eye colour, hair colour, height
define chromosome
-made of DNA which contains genetic info in the form of genes
eg.
-46 chromo. (23 pairs) in every nucleus - 23 from sperm, 23 from egg
-arranged in pairs
define gene
-a length of DNA that codes for a protein
-eg. brown eyed protein
define Allele
-an alternative version of a gene
-eg. brown eyed allele
define haploid nucleus
-nucleus containing a single set of chromo.
eg. gametes, pollen & ovaries
define diploid nucleus
-nucleus containing 2 sets of chromo.
eg. in all body cells (2n = 46 [in pairs])
define gametes
sex cells ( sperm & egg)
define zygote
-fertilized egg
how to make a zygote
-sperm + egg -> zygote
- 23 chromo. [n] + 23 chromo. [n] -> 46 chromo [2n]
23rd chromo. of males & females
-male = XY
-female = XX
chromo. of egg
X, X
chromo. of sprem
X, Y
-50% - X, 50% - Y
% of gender out come as girl/ boy
50%