IB DP Biology: SL复习笔记3.3.3 Skills: Inheritance
Constructing Punnett Grids A?monohybrid trait?is one that is controlled by only?one gene Generally, we consider that such a gene has?two alleles Either: one allele is dominant and the other is rece...
IB DP Biology: SL复习笔记3.3.2 Inheriting Alleles
Segregation of Alleles Meiosis is a form of?nuclear division?that results in the?production of?haploid?cells?from diploid cells During meiosis a diploid cell will?divide twice?to form?four haploid ...
IB DP Biology: SL复习笔记3.3.1 Inheritance
Mendel's Experiments Gregor Mendel?was an Austrian monk He was trained in mathematics and natural history at the University of Vienna In the mid-19th century, Mendel carried out breeding experiment...
IB DP Biology: SL复习笔记3.2.5 Skills: Meiosis
Drawing the Stages of Meiosis Cells undergoing?meiosis?can be observed and photographed using specialized microscopes The different stages of meiosis have distinctive characteristics meaning they c...
IB DP Biology: SL复习笔记3.2.4 Non-disjunction
Non-disjunction Non-disjunction?occurs when chromosomes fail to separate correctly during?meiosis This can occur in either anaphase I or anaphase II, leading to?gametes?forming with an?abnormal num...
IB DP Biology: SL复习笔记3.2.3 Genetic Variation
Genetic Variation & Meiosis Crossing over and random orientation promote genetic variation Having?genetically different offspring?can be?advantageous?for natural selection and therefore increas...
IB DP Biology: SL复习笔记3.2.2 Stages of Meiosis
DNA Replication before Meiosis Before meiosis occurs, all of the DNA inside the nucleus of the 'parent' cell is?replicated This occurs during a period of the cell cycle known as?interphase Once thi...
IB DP Biology: SL复习笔记3.2.1 Meiosis
Meiosis There are two processes by which the?nucleus?of a?eukaryotic cell?can?divide. These are: Mitosis Meiosis Mitosis?gives rise to?genetically identical cells?and is the type of cell division u...
IB DP Biology: SL复习笔记3.1.10 Skills: Using Databases
Use of Databases to Identify Gene Loci Use of databases to identify the locus of a human gene and its polypeptide product Following the?sequencing of the whole human genome, we now know the?exact l...
