Variation Flashcards
(27 cards)
What is variation within a species?
Variation within a species refers to the differences among organisms of the same species, which can be genetic or environmental.
Examples include different breeds of dogs, such as Dalmatians and Pugs.
What causes genetic variation within a species?
Genetic variation is caused by different alleles (versions of genes) and can arise from mutations and sexual reproduction.
Sexual reproduction combines alleles in various ways, leading to diverse offspring.
Fill in the blank: Genetic variation can be caused by _______ arising through mutations.
new alleles
What are acquired characteristics?
Acquired characteristics are traits that organisms gain during their lifetimes due to environmental factors.
For example, a plant’s growth can be affected by sunlight availability.
How does the environment affect phenotype?
The environment influences phenotype by determining how much an organism can express its genetic potential.
For instance, a plant’s maximum height is genetically determined, but its actual height depends on environmental conditions.
What are mutations?
Mutations are changes to the base sequence of DNA that can result in new alleles.
Mutations can be neutral or may slightly alter an organism’s phenotype.
True or False: Most mutations have a significant effect on an organism’s phenotype.
False
What is the effect of a rare mutation on phenotype?
A rare mutation can have a big effect on phenotype, potentially leading to the production of non-functional proteins.
An example is cystic fibrosis, where a mutation disrupts protein function related to salt and water movement in cells.
What is the role of new combinations of alleles in variation?
New combinations of alleles may interact to produce new phenotypes.
This interaction can lead to diverse characteristics within a population.
Fill in the blank: Most variation in phenotype is determined by a mixture of _______ and environmental factors.
genetic
What is the relationship between genetic and environmental influences on variation?
The variation seen in organisms is a complex mixture of genetic and environmental influences, often making it difficult to assess which is more influential.
This complexity is illustrated by factors such as British weather affecting plant growth.
What is the Human Genome Project?
A scientific project aimed to map all human genes
It has been described as one of the most exciting developments in recent science.
What have scientists identified about genes related to disease through the Human Genome Project?
About 1,800 genes related to disease
What is one potential medical application of the Human Genome Project’s research?
Prediction and prevention of diseases
Fill in the blank: Many common diseases are caused by the interaction of different genes and _______.
lifestyle factors
What is the benefit of knowing which genes predispose individuals to diseases?
Tailored advice on diet and lifestyle
What kind of disorders can be tested thanks to the Human Genome Project?
Inherited disorders
Give an example of an inherited disorder.
Cystic fibrosis
What has the Human Genome Project enabled scientists to do more quickly?
Identify genes and alleles causing inherited disorders
What can be developed once a disease-causing allele is identified?
Better treatments or cures
How has genome research impacted drug design?
It allows for drugs tailored to specific genetic variations
What can tests currently identify regarding breast cancer?
Whether a patient will respond to a particular drug
True or False: Genome research can lead to more effective treatments with fewer side effects.
True
What is one potential drawback of knowing one’s genetic predisposition to diseases?
Increased stress
