Year 8 Biology - Genes Flashcards
What is the theory of Natural Selection?
Natural selection is the idea that organisms best suited to their environment are more likely to survive and reproduce.
Why do species evolve over time?
Species change to fit where they live, win against others, and reproduce easier.
What is the process of peer review?
In peer review, experts check research to make sure it’s accurate, and right for publishing in science journals.
Evaluate the evidence that Darwin used to develop his theory of Natural Selection?
Darwin used observations of different species and fossil records to support his theory and showing how traits changes over time.
What factors may lead to extinction?
Habitat loss, unable to adapt to its environment, pollution and competitions from predators.
What is the importance of biodiversity in maintaining plant and animals populations?
Biodiversity helps plants and animals by giving them different genes, making them strong against changes, and keeping ecosystems balanced.
Why might a species become extinct?
A species might become extinct due to habitat loss, pollution, climate change or disease.
How might lack of biodiversity affect an ecosystem?
Lack of biodiversity can disrupt food webs, and have fewer types of plants and animals makes nature less able to handle big changes.
What does it mean by an endangered species?
An endangered species is one that is at risk of extinction due to low population numbers.
What techniques are used to preserve extinction?
habitat protection, captive breeding, and public awareness campaigns.
How does preserving biodiversity benefit humans?
Preserving biodiversity ensures essential resources, such as food, medicines, and clean air and water,.
How are characteristic inherited?
You inherit characteristics from your parents through genetic material stored in the nucleus of your cells.
Describe the relationship between DNA, genes and chromosomes?
DNA contains genes, which are segments of DNA. Chromosomes are structures that contain many genes.
How does a DNA mutation affect an organism and future offspring?
A DNA mutation can change traits, affecting an organism’s health and potentially passing on changes to offspring.
Describe the structure of DNA?
DNA is a double helix, containing of two long strands twisted around each other, with steps made of nucleotide bases.
How did scientist work together to discover the structure of DNA?
Scientists like Watson worked using X-ray crystallography and model building, to show DNA’s structure.
What’s the difference between dominant and recessive alleles?
Dominant alleles mask the effect of recessive alleles when present together, determining an organism’s trait expression.
How can a Punnett square be used to demonstrate the inheritance of genes?
A Punnett square predicts possible gene combinations in offspring from parental genotypes, showing inheritance patterns.
Why are offspring’s not identical to their parents?
Children get some genes from each parent making them different from their parents and each other.
How is a product produced using genetic modification?
Genetic modification adds new genes to an organism’s DNA to give it desired traits.
Describe some advantages of genetic modification?
Genetic modification can boost crop yield, make plants pest-resistant, improve nutrition, and lower costs.
