Flashcards
DNA the molecule
Flashcards do conjunto (19)
- 1Deoxyribonucleic acidDeoxyribonucleic acid (DNA) is the molecule that determines their characteristics.
- 2What is nucleotides? And how many parts does it have?DNA has the same structure in all organisms in that it is made up of smaller molecules called nucleotides. Nucleotide molecules have three parts:
1. phosphate group
2. deoxyribose sugar
3. one of four nitrogen-rich bases.
- 3What is a double helix?the shape of a double helix is like that of a twisted rope ladder.
- 4Nitrogen rich base: adenine(A), thymine(T), guanine(G) and cytosine(C):all have different chemical structures and shapes that complement each other. this means that they can only pair up in one way.
- 5adenine(A)Nitrogen-rich base; forms pair with thymine (T)
- 6thymine (T)Nitrogen-rich base; forms pair with adenine (A)
- 7guanine (G)nitrogen-rich base; forms pair with cytosine (C)
- 8ChromosomesChromosomes are long, thin, thread-like structures found in the nuclei of all cells in the human body that contain a nucleus.
- 9chromosome numberin your body cells, there are 46 chromosomes, half of which came from your father and half from your mother.
- 10sex chromosomes'X' and 'Y' Chromosome those who determine wether you are male or females:
in females, the sex chromosomes are a pair of x chromosomes (XX)
in males, the sex chromosomes are one X and one Y chromosome (XY)
- 11Homologous chromosomes:-are the same length
-have a structure called centromere in the same position.
-have genes for particular characteristics at the same location along their length.
- 12What is gene?Genes are sections of DNA arranged along the chromosomes. the number of genes on a chromosome ranges from around 200 to 2000.
- 13differences between genes and the next:-the order of bases along the DNA stand
-number of bases in that section of DNA
- 14the order of the bases along the DNA standis the genetic code. each genes codes )(contains instructions) for a specific protein.
- 15what kinds of protein are-structural, such as collagen
-enzymes, such as amylase
-regulatory, such as growth hormone
- 16The unique characteristics of organisms:different versions of genes are found in different organisms. for example:
dogs and snakes both have a gene for the keratin protein, but the gene is little different. - 17Watson-Crick modelthe double helix structure of the DNA molecule
- 18what does centromere means?the point on a chromosome where two chromatids are joined together.
- 19what does dogs and snakes?dogs and snakes both have