What type of reproduction involves two parents combining genetic material?
Sexual reproduction
What is heredity?
The passing of traits from parents to offspring
What is incomplete dominance?
A blend of traits (e.g., red + white = pink)
What organelle stores genetic material?
The nucleus
What is the independent variable in an experiment?
The factor that is changed
Why does asexual reproduction produce identical offspring?
There’s only one parent, so DNA is copied exactly
What do we call the different forms of a gene?
Alleles
What is codominance?
Both traits show (e.g., red and white spots)
What is the main function of DNA?
To carry instructions for traits and cell activities
Why are controlled variables important?
They ensure only one factor is tested at a time
What is one disadvantage of sexual reproduction compared to asexual?
It takes more time and energy
How can two parents with brown eyes have a child with blue eyes?
Both parents carry a recessive blue-eye allele
If two heterozygous plants (Rr × Rr) are crossed, what’s the genotype ratio?
1 RR : 2 Rr : 1 rr
What process allows multicellular organisms to grow?
Mitosis
Give an example of an adaptation that helps an animal survive.
Thick fur for cold climates; long necks to reach food
Which type of reproduction increases genetic diversity, and why is that beneficial?
Sexual reproduction; helps populations survive environmental changes
Explain how environment can influence a trait that’s usually genetic.
Environmental conditions can affect gene expression (e.g., nutrition affecting height)
In humans, blood type shows codominance. Which alleles make blood type AB?
A and B alleles
How does DNA determine an organism’s traits?
It codes for proteins that express traits
Why might a gray rat snake survive better in a rocky habitat than a green one?
Camouflage helps it hide from predators
Some lizards can reproduce without males. What type of reproduction is this, and what is a possible drawback?
Asexual reproduction; less genetic variation means less adaptability
If a gene has two alleles, R (dominant) and r (recessive), what percentage of offspring will show the dominant trait if both parents are Rr?
75%
A white flower and red flower produce pink offspring. Predict what would happen if two pink offspring were crossed.
25% red, 50% pink, 25% white
What would happen if DNA in a cell were damaged and not repaired?
The cell might malfunction or die; could lead to mutations
Explain how genetic variation supports natural selection.
Variation allows some individuals to survive changes and pass on beneficial traits.