Sexual Reproduction
What is sexual reproduction?
The process of producing offspring by combining genetic material from two parents.
What is natural selection?
The process where organisms with helpful traits survive and reproduce more.
What is asexual reproduction?
When one parent produces offspring that are genetically identical to itself.
What is a gene?
A piece of DNA that determines a trait.
Which type of reproduction-sexual or asexual-would allow a species to adapt more quickly in a homogenous environment?
Asexual reproduction.
What are the male and female reproductive cells called?
Sperm and egg
What is an adaptation?
A trait that helps an organism survive in its environment.
What is the main advantage of asexual reproduction?
It's fast and doesn't require a partner.
What do we call different versions of a gene?
Alleles
They will likely all die because they have identical DNA
Offspring from sexual reproduction show genetic variation. What does “variation” mean?
Differences in traits among individuals.
Why do populations change over time through natural selection?
Helpful traits become more common.
Name one type of asexual reproduction.
If "T" is dominant for tall plants and "t" is recessive for short plants, what genotype must a plant have to be short?
tt.
Without drawing a Punnett square, if two parents both have the genotype Bb for eye color, what percentage of their offspring are expected to show the dominant trait?
75%
What is fertilization?
When a sperm cell joins an egg cell.
What is "survival of the fittest" referring to?
Organisms best suited to their environment survive long enough to reproduce.
Why are asexually produced offspring usually identical to the parent?
Because all their DNA comes from a single parent.
What is a Punnett square used for?
Predicting the probability of traits in offspring.
Explain how natural selection and genetic variation work together to change a population over time.
Variation provides differences, natural selection favors helpful differences.
Why does sexual reproduction lead to greater diversity in a population?
Because offspring inherit different combinations of genes from each parent.
Give an example of natural selection in action.
Galapagos Finches beaks changing depending on their environment.
Name one disadvantage of asexual reproduction.
Lack of genetic variation; a harmful change can affect all offspring.
What does the terms "phenotype" and "genotype" mean?
The physical expression of a trait. The different versions of the trait in the gene on the DNA (the alleles).
A population of beetles has two alleles for shell color: G (green, dominant) and g (brown, recessive). Birds can see green beetles more easily than brown ones.
Over time, the environment becomes darker because of a fire.
Question:
Predict how the frequency of the g allele might change over several generations. Explain why using both genetics and natural selection.
Variable answer.