Reproduction
What is asexual reproduction?
One parent produces genetically identical offspring.
What is genetic cloning?
The deliberate production of genetically identical individuals.
What is an adaptation?
A heritable trait that helps an organism survive and reproduce in its environment.
Name one major environmental stress faced by desert organisms.
Extreme temperatures or lack of water.
What is a population?
All members of a species living in one place at one time.
What is the main difference between sexual and asexual reproduction?
Sexual reproduction involves two parents and produces genetically unique offspring; asexual reproduction involves one parent and produces genetically identical offspring.
Name the type of asexual reproduction where a growth develops on the parent and eventually breaks off.
Budding.
Name the three types of adaptations.
Structural, behavioural and physiological.
Why does thick fur help an Arctic animal survive?
It provides insulation and reduces heat loss.
What is the difference between an abiotic and biotic factor?
Abiotic factors are non-living; biotic factors are living.
Give one advantage and one disadvantage of sexual reproduction.
Advantage: increases genetic diversity. Disadvantage: requires time/energy to find a mate.
In somatic cell nuclear transfer, what is removed from the egg cell before the donor nucleus is inserted?
The nucleus
A desert animal is nocturnal and has large ears. Identify the type of adaptation represented by each and explain the benefit of one.
Nocturnal = behavioural; large ears = structural. Nocturnal behaviour avoids daytime heat; large ears increase surface area for heat loss.
Why are small ears advantageous for animals living in cold environments?
They provide less surface area through which heat can be lost.
A clownfish gains shelter from an anemone, while the anemone is unaffected. What interaction is this?
Commensalism.
Explain why genetic diversity increases a population's ability to survive environmental change.
Greater genetic variation means some individuals may have traits that allow them to survive changing conditions and reproduce.
Describe the basic process of SCNT.
The nucleus from a somatic cell is inserted into an egg cell whose nucleus has been removed. The egg is stimulated to divide and is implanted into a surrogate.
Explain how sunken stomata help a desert plant survive.
They create a more humid environment around the stomata, reducing water loss through transpiration.
Explain how huddling helps animals survive in cold environments.
Huddling reduces the surface area exposed to the environment, reducing heat loss.
A flea feeds on a dog without usually killing it. What interaction is this, and which organism is the host?
Parasitism; the dog is the host.
A species reproduces asexually and all individuals are genetically very similar. A new disease enters the environment. Explain why this could cause a major decline in the population.
Low genetic diversity means individuals are likely to have similar susceptibility to the disease. Few/no individuals may possess alleles that provide resistance, so many could die.
Explain two potential problems associated with SCNT.
It may take many attempts to produce a successful clone, and clones may develop abnormalities or age-related diseases.
A desert plant has both a deep root system and shallow, wide roots. Explain how these two adaptations help the plant obtain water.
Deep roots access underground water, while shallow, wide roots allow rapid absorption of water when rainfall occurs.
Explain why larger-bodied individuals are generally better adapted to cold environments, referring to surface area-to-volume ratio.
Larger individuals have a smaller surface area-to-volume ratio, so they lose less heat relative to their volume.
Explain why elephants can be considered a keystone species if their removal causes savannah grasslands to become forested.
Elephants have a disproportionately large role in maintaining the ecosystem. Their feeding prevents trees from taking over, helping maintain grasslands that support other species.