Connect the terms with their corresponding explanations. The terms are presented in a chronological order - the number before an explanation refers to the chapter where the term is introduced.

Choose the terms from the following list:

19. A hereditary factor.
19. The part of the cell where the chromosomes are stored.
19. The normal number of chromosomes in most human cells.
19. The number of chromosomes in human sex cells.
19. The appearance of an individual, influenced by the genotype as well as environmental factors.

20. A gene form.
20. If both homologous chromosomes contain the same allele of the gene, the chromosome pair is:
20. Alleles marked with capital letters are alleles.
20. A characteristic or trait that has not been inherited is called an characteristic.


21. A microscopically small organism.
21. A pathogen group that is not considered a living organism.
21. The outermost layer of the skin that consists of dead cells.
21. The layer of the skin located below the epidermis.
21. A blood cell type that kills and consumes pathogens.
21. A microscopically small, unicellular organism.
21. A type of pharmaceutical that can be used to fight bacteria.

22. A food product that is beneficial to health is considered .
22. A process that can be used to create new, better agricultural plant species.
22. A three-letter acronym that means an genetically modified organism.
22. A process that can be used to create genetically identical individuals.
22. A cell that is capable of differentiating into other cell types.


23. A petrified remnant of a dead organism. .
23. A process in which a species develops gradually in accordance to natural selection.
23. A phenomenon where the fittest individuals of a species produce the most offspring.
23. An organ or part of the body that has lost its original purpose.
23. A species that has not changed drastically during thousands of years, e.g. the hedgehog, is called a fossil.
23. The scientist that first developed the modern theory of evolution.
23. The type of oxygen that protects the Earth from UV radiation.

24. A small primate that is closely related to modern humans.
24. The continent where modern humans have evolved.
24. A human species that inhabited Europe approximately 30 000 years ago.
24. The scientific name of the modern human is Homo