variation , evolution + genetic engineering flashcards

All 25 cards

1. Card 1

   Define 'variation' as it relates to individuals within a species.

   Variation is defined as the differences observed between individuals belonging to the same species. These differences can arise from either environmental or genetic factors.

2. Card 2

   Explain how sexual reproduction contributes to genetic variation within a species.

   Sexual reproduction causes variation because offspring receive one set of genetic information from each parent. This process, particularly through meiosis, shuffles the genes, resulting in a unique combination of genes in the offspring that differs from either parent.

3. Card 3

   What is a mutation, and what are the two main types of mutations mentioned?

   A mutation is a change in the structure or amount of DNA in an organism. The two main types of mutations are gene mutations and chromosome mutations.

4. Card 4

   Describe a gene mutation and provide an example of a human condition caused by it.

   A gene mutation occurs when genes, which code for proteins, are damaged or copied incorrectly, leading to the production of a new protein that may not function properly. Examples include Cystic fibrosis and Haemophilia.

5. Card 5

   Explain what a chromosome mutation is and give a human example.

   A chromosome mutation involves a change in an individual chromosome's structure or a change in the total number of chromosomes. Down syndrome, caused by an extra chromosome 21, is an example of a chromosome mutation in humans.

6. Card 6

   Identify two distinct sources or causes of mutations.

   Mutations can be caused by spontaneous changes resulting from mistakes in DNA replication, or by mutagens. Mutagens are agents such as ionizing radiation (e.g., UV rays, X-rays) and certain chemicals (e.g., tobacco smoke, formaldehyde) that alter DNA in a cell.

7. Card 7

   Define 'evolution' according to the provided notes.

   Evolution is defined as the changes between members of a species and the emergence of new species from older species over time. These changes occur in response to environmental shifts, primarily driven by natural selection.

8. Card 8

   What is 'natural selection' and how does it relate to genetic traits?

   Natural selection is the mechanism by which members of a species possessing genetic traits that enhance their survival in a specific environment are more likely to reproduce. Consequently, they pass these advantageous traits on to the next generation, leading to the prevalence of these traits over time.

9. Card 9

   State Darwin's (and Wallace's) first two observations that led to the theory of natural selection.

   Darwin's and Wallace's first two observations were that organisms overbreed and that population numbers tend to remain constant. These observations led them to conclude that there must be a struggle for existence among organisms.

10. Card 10

    How did Darwin's third observation, regarding inherited variations, contribute to the concept of 'survival of the fittest'?

    Darwin's third observation noted that inherited variations occur in populations. This led him to conclude that organisms possessing traits necessary for survival would reproduce and pass these traits on, a concept encapsulated by 'survival of the fittest' or natural selection.

11. Card 11

    Provide one source of evidence for the theory of evolution as mentioned in the notes.

    Fossils provide significant evidence for evolution. The study of fossils, known as palaeontology, reveals how life has changed over time, become more complex, and how these changes can be linked to environmental shifts.

12. Card 12

    What is 'speciation' in the context of evolution?

    Speciation is the process by which new species are produced as a direct result of evolution. It signifies the divergence of populations into distinct species over time.

13. Card 13

    Define 'genetic engineering'.

    Genetic engineering is the artificial alteration and manipulation of genes. It involves directly modifying an organism's DNA to introduce new traits or remove existing ones.

14. Card 14

    What is 'recombinant DNA' and what are organisms containing it called?

    Recombinant DNA refers to altered genes where DNA from different species has been combined. Organisms that contain recombinant DNA are known as Genetically Modified Organisms (GMOs).

15. Card 15

    Name three essential components required to form recombinant DNA.

    To form recombinant DNA, a source of DNA called the target gene, a cloning vector (such as a bacterial plasmid), and a restriction enzyme to cut DNA at specific places are required. Additionally, DNA ligase is needed to join the fragments.

16. Card 16

    Briefly describe the 'cutting the DNA' step in genetic engineering.

    In the 'cutting the DNA' step of genetic engineering, both the target gene (from the source DNA) and the plasmid DNA (from the cloning vector) are precisely cut using a restriction enzyme. This creates compatible ends for joining.

17. Card 17

    What is the purpose of the enzyme DNA ligase in genetic engineering?

    The enzyme DNA ligase is crucial in genetic engineering as it causes the target gene to join with the DNA of the cloning vector. This joining forms the recombinant DNA molecule.

18. Card 18

    Explain the 'transformation' step in the genetic engineering process.

    Transformation is the step where the newly created recombinant DNA is introduced into the desired host cell. This cell will then take up and potentially express the new genetic material.

19. Card 19

    What is the 'cloning' step in genetic engineering, and why is it performed?

    The 'cloning' step involves making identical copies of the new genetically engineered transformed organism. This is done to produce a sufficient number of organisms containing the recombinant DNA for further study or product expression.

20. Card 20

    Describe one application of genetic engineering in plants.

    One application of genetic engineering in plants is the creation of weed killer resistant crops. This involves inserting a bacterial gene for herbicide resistance into crop plants, allowing the herbicide to kill weeds without harming the crop.

21. Card 21

    Give an example of how genetic engineering is applied in animals.

    In animals, genetic engineering can be used to make sheep produce proteins to treat human diseases. For instance, a human gene for a lung-protecting protein can be inserted into sheep DNA, causing the sheep to produce this protein in their milk.

22. Card 22

    How is genetic engineering used with bacteria to benefit human health?

    Genetic engineering is used with bacteria to produce human insulin. The gene for human insulin is inserted into a bacterium, which then produces human insulin that can be used by diabetics.

23. Card 23

    Distinguish between 'inherited variations' and 'acquired variations'.

    Inherited variations are differences within a species that are controlled by genes and passed down from parents. Acquired variations, in contrast, are differences that develop or are learned over an organism's lifetime and are not genetically determined or passed on.

24. Card 24

    Why is the survival rate of mutations generally very low?

    The survival rate of mutations is generally very low due to the activity of enzymes that repair damaged DNA. These repair mechanisms effectively correct many mutations, thus keeping their frequency low.

25. Card 25

    What is the significance of a mutation occurring in gamete cells versus somatic cells?

    A mutation in somatic cells may not be harmful to the organism, and it is not passed on to offspring. However, a mutation in gamete cells (sex cells) can be significant because it will be passed on to the next generation, potentially affecting the offspring's traits or health.

More flashcard decks

• Thermochemistry and Thermodynamics flashcards (149 cards)
• Género Bacillus y Clostridium flashcards (100 cards)
• Ψηφιακά Παιχνίδια και Μάθηση flashcards (100 cards)
• Philosophy AS flashcards (100 cards)
• Nervous system flashcards (100 cards)
• ECG, IGEL and Iv flashcards (100 cards)

Browse every shared deck