biology

• mitosis - the process of making new body cells.
• meiosis - the process that makes gametes (eggs or sperm).
• the cell cycle consists of interphase and mitosis/meiosis.
• cell division is important because it allows organisms to grow, repair damaged tissues, replace old cells with new ones, and reproduce sexually.
• interphase is when the cell grows and prepares for division.
• mitosis is where the chromosomes are copied and then separated into two identical daughter cells.
• Cytokinesis: the cytoplasmic division of a cell at the end of mitosis or meiosis, bringing about the separation into two daughter cells.
• what re the stages of mitosis

  • prophase
  • metaphase
  • anaphase
  • telophase
• in prophase, the nuclear envelope breaks down and spindle fibers form around the centrosome.
• chromatin condenses into visible chromosomes during metaphase.
• during anaphase, sister chromatids separate from one another and move towards opposite poles of the cell.
• the nucleolus disappears and the chromosomes begin to uncoil during telophase.
• RNA and DNA has 3 parts

  • phosphate
  • sugar
  • nitrogenous base
• DNA is double stranded while RNA is single stranded
• DNA is found in the nucleus while RNA can be found in the cytoplasm or nucleus
• DNA contains thymine while RNA contains uracil
• DNA is made up of deoxyribose sugar while RNA is made up of ribose sugar
• DNA stores genetic information, while RNA carries out instructions from that info
• RNA - is the messenger molecule that carries the genetic information from DNA to the ribosome
• mRNA - transfers the code from DNA to the ribosomes where protein synthesis occurs
• rRNA - makes up part of the structure of the ribosome
• tRNA - brings amino acids to the ribosome during translation
• The three main types of RNA are mRNA (messenger), rRNA (ribosomal) and tRNA (transfer)
• XX and XY chromosome are homologous pairs, they are identical in structure and function
• Homozygous means having two copies of the same allele
• Sex chromosomes determine whether an individual will be male or female
• Heterozygous means having two different alleles at one locus on a pair of homologous chromosomes
• A dominant trait is expressed when only one copy of an allele is present
• A gene is a section of DNA that codes for a specific protein
• Gamete - A sex cell that contains half the number of chromosomes as a normal cell.