The flashcards below were created by user
heidi.tjeerdsma
on FreezingBlue Flashcards.
-
Inheritance occurs because of what?
genes
-
What are genes made of?
DNA
-
What does a gene do?
provides the information needed to put amino acids in the right order to make one protein
-
What is DNA made of?
nucleotides
-
What are the three parts of a nucleotide?
- Sugar (deoxyribose)
- A phosphate
- A base
-
What are the four possible bases of a nucleotide?
- Adenine
- Thymine
- Cytosine
- Guanine
-
What is the structure of DNA?
double helix (2 strands) connected by the bases in the middle
-
Who found the DNA structure?
James Watson, Francis Crick, Rosalind Franklin
-
Which of the three parts of a nucleotide make the backbone of DNA?
sugar and the phosphate (sides of the ladder)
-
What holds the two strands of DNA together?
hydrogen bonding between bases
-
What are the two strands of DNA in the helix?
anti-parallel (the same distance apart, but each strand starts at opposite ends of the DNA)
-
Why do bases always pair?
so that a base with one ring is paired with a base with two rings
-
What does DNA use as its alphabet?
the bases
-
What happens by putting bases in a different order?
you can make different proteins
-
What is making two identical double helixes?
DNA replication
-
What are the parts for DNA replication?
- Enzymes
- Parent DNA strands
- More nucleotides to make the new strand
-
What means each new DNA helix has one new and one old DNA strand?
semi-conservative
-
What are the steps to replication?
- An enzyme called helicase unwinds the helix to make a replication bubble.
- A second enzyme (DNA polymerase) pairs up the strands with new nucleotides, then connects the backbone of the new nucleotides.
- A third enzyme (DNA ligase) attaches the completed pieces together until it is one long strand of DNA.
-
How rare is it to have a mistake in DNA strands?
around 1 mistake for every billion base pairs
-
What is a change in the sequence of bases in DNA?
mutation
-
How can mutations happen?
due to exposure to things that damage DNA, such as chemicals, sunlight, and cosmic rays
-
What are the types of mutations?
-
Which type of mutation is a small error and does not affect the gene?
neutral
-
Which type of mutation is a large error and makes the whole gene wrong and is less likely to survive?
harmful
-
Which type of mutation is a small error and makes the gene better and may protect against AIDS?
beneficial
|
|