IB DP Biology: HL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: HL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: HL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: HL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...
IB DP Biology: HL复习笔记3.1.9 Karyograms
Karyograms During the stages of mitosis,?chromosomes condense?(become visible) This is most notable in?metaphase Staining?can reveal distinctive banding patterns on chromosomes at this stage The?po...
IB DP Biology: HL复习笔记3.1.8 Sex Determination
Sex Determination Sex is determined by an?entire chromosome pair?(as opposed to most other characteristics that are just determined by one or a number of genes) Females?have the sex chromosomes (pa...
IB DP Biology: HL复习笔记3.1.7 Chromosome Number
Haploid Haploid nuclei have one chromosome of each pair Haploid cells contain?one complete set of chromosomes (n) In other words, they have?half?the number of chromosomes compared to normal body ce...
IB DP Biology: HL复习笔记3.1.6 Eukaryotic Chromosomes
Eukaryotic Chromosomes Chromosomes in eukaryotic cells are?one,?very long?DNA molecule associated with proteins The main proteins present are the large, positively charged globular proteins called?...
IB DP Biology: HL复习笔记3.1.5 Prokaryotic Chromosomes
Prokaryotic Chromosomes The DNA in prokaryotic cells is significantly different from the DNA found in eukaryotic cells Prokaryotes?do not contain a nucleus?therefore the DNA is located in the cytop...
