DNA, chromosomes and genes
y chromosome gives the trait of being ______ x chromosome gives the trait of being _____
male, female
the number of different chromosomes a cells contains is represented by letter __
n (italic)
Where does each chromosome in the pair come from?
one from your father and one from your mother
There are generally two types of cells in the humain body:
somatic and reproductive
genes tell your cells...
what to do
The 23rd pair of chromosomes are both ___ in woman but are __ and ___ in men
x, x, y
zygote
- formed by the joining of 2 haploid cells (sperm + egg) - - single diploid cell with a full set of DNA
reproductive cells:
-are involved in reproduction -have n chromosomes=haploid cells -haploid cells contain only one set of each chromosome
somatic cells:
-form a tissu -have 2n chromosomes=diploid cells -diploid cells contain 2 sets of chromosomes
___ of the pairs of the chromosomes in both males and females are the same. The other pair(s) is called __ __ _______
22, the sex chromosome
you get ___ chromosomes from your mom and _____ from your dad. You have ____ in total.
23, 23, 46
The nucleus of human somatic cells (exception of reproductive cells) contain ___ pairs of chromosomes = total of ___ chromosomes
23, 46
What is DNA made of? (what links with what)
4 nitrogen containing bases: Adenine, Thymine, Cytosine and Guanine (A links with T and C links with G)
What is a gene?
A gene is a segment of DNA that determines a particular genetic characteristic and encodes for heredity traits such as eye color.
What is a chromosome?
A structure of condensed DNA that therefore contains genes.
True or false: Humans all have the same genetic code.
False
True or false: Plants do not have chromosomes.
False
True or false: there are 30 000 genes in a cell
False
True or false: a human cell has 23 chromosomes.
False, we have 23 PAIRS of chromosomes
True or false: A chromosome is shaped like sticks.
True
True or false: A gene is a section of a thread of DNA.
True
True or false: Genes are a source of heredity.
True
What is a DNA molecule:
a molecule that contains genetic information for the proper function of cells. It forms a double helix.
A chromosome is usually called a ___ during the process of cell division.
chromatid
DNA molecules are packed into something called _____
chromosomes
each species has a characteristic number of ____
chromosomes
genes are made of ______ ____ _____ (DNA)
deoxyribose nucleic acid
The number of chromosomes does/doesn't determine the complexity of an organism
doesn't
3 reasons why cells divide:
for growth, creation of reproductive cells, to repair tissue
Place the following structure in increasing order of size: cell, gene, DNA, chromosome, nucleus, stomach tissu
gene, DNA, chromosome, nucleus, cell, stomach tissu
