SB3 Key Words Flashcards
Fertilisation?
Fusing of a male gamete with a female gamete.
Clone?
All the cells in a clone are genetically identical to each other and to the parent’s cells.
Vertebrate?
Animal with bones, such as a human.
Invertebrate?
An animal without bones, such as an insect or worm.
Mitosis?
The process of diploid cells dividing to produce two diploid daughter cells that are genetically identical to the parent.
Asexual reproduction?
Producing new organisms from one parent only. These organisms are genetically identical to the parent.
Variation?
Differences in the characteristics of organisms?
Sexual reproduction?
Reproduction that needs a male and a female parent.
Chromosome?
A structure found in the nuclei of cells. Each chromosome contains one enormously long DNA molecule packed up with proteins.
DNA?
Deoxyribonucleic acid. A polymer made of sugar and phosphate groups joined to bases. One molecule of DNA is found in each chromosome.
Egg cell?
The female gamete in humans.
Genome?
All the DNA in an organism. Each body cell contains a copy of the genome.
Haploid?
A cell or nucleus that has one set of chromosomes. Gametes are haploid.
Sperm cell?
The male gamete in humans.
Gamete?
A haploid cell used for sexual reproduction.
Meiosis?
A form of cell division in which one parent cell produces four haploid daughter cells.
Daughter cell?
A cell produced by another cell that has divided.
Polymer?
A molecule made out of a chain of repeating similar units (called monomers).
Zygote?
Another term for fertilised egg cell.
Replicate? (DNA)
When DNA makes a copy of itself.
Gene?
Section of the long strand of DNA found in a chromosome, which often contains instructions for a protein.
Diploid?
A cell or nucleus that has two sets of chromosomes. In humans, almost all cells except the sperm and egg cells are diploid.
Hydrogen bond?
Weak force of attraction caused by differences in the electrical charge on different parts of different molecules.
Base (in DNA)?
Four substances that help make up DNA, often shown by the letters A, C, G and T. Pairs of bases form ‘links’ between two ‘spines’ formed of phosphate groups and a type of sugar.
Adenine?
One of four bases found in DNA. Often written as A.
Complementary base pair?
Two DNA bases that fit into each other and link by hydrogen bonds. A + T and C + G
Cytosine?
One of four bases found in DNA. Often written as C.
Double helix?
Two helices joined together.
Guanine?
One of four bases found in DNA. Often written as G.
Thymine?
One of four bases found in DNA. Often written as T.