Bio Unit 2 Sac 3 AOS 2

What is genetic diversity?

The amount of genetic variation that exists between individuals measured by reference to the populations gene pool

What is a gene pool?

The sum of all the different genes and alleles present in a population.

Why is genetic diversity important?

It protects the longevity of a species by guarding against environmental changes, such as new diseases or predators.

How does a larger gene pool benefit a population?

It increases resilience to environmental changes by containing more alleles that may be adapted to survive new challenges.

What is sexual reproduction?

the fusion of two haploid gametes to form a genetically unique diploid zygote.

What are reproductive strategies?

Different methods organisms use to reproduce, influenced by environmental pressures.

What is fertilisation?

The process of fusion of two haploid gametes.

What is a zygote?

A single, genetically unique cell formed from the fusion of gametes.

What is asexual reproduction?

A method of reproduction that does not involve the fusion of gametes, resulting in offspring that are clones of the parent.

What is binary fission?

A common form of asexual reproduction where an organism splits into two equally sized clones.

What is budding?

A form of asexual reproduction where a new organism develops from an outgrowth or bud on the parent.

What are the advantages of sexual reproduction?

Increased genetic diversity, which enhances adaptability and survival of offspring.

What are the disadvantages of sexual reproduction?

It typically requires more time and energy to find a mate and produce offspring.

What are the advantages of asexual reproduction?

It allows for rapid population growth and does not require a mate.

What are the disadvantages of asexual reproduction?

Lack of genetic diversity can make populations more vulnerable to environmental changes.

What is the impact of environmental pressures on reproductive strategies?

They influence the evolution of different reproductive methods to enhance survival.

How do mutations affect genetic diversity?

Mutations introduce new alleles into the gene pool, increasing genetic variation.

What role does natural selection play in genetic diversity?

It favors alleles that provide advantages in survival and reproduction, shaping the gene pool.

What is gene flow?

The transfer of alleles or genes from one population to another, increasing genetic diversity.

What is genetic drift?

A mechanism of evolution that causes random changes in allele frequencies in a population.

What is vegetative propagation?

A form of asexual reproduction where new plants grow from parts of the parent plant.

What is sporogenesis?

The process of forming spores, which can develop into new individuals without fertilization.

What is parthenogenesis?

A form of asexual reproduction where an egg develops into a new individual without fertilization.

What is the significance of a diverse gene pool in a population?

It enhances the population's ability to adapt to changing environments and resist diseases.

How does sexual reproduction contribute to genetic diversity?

It combines genetic material from two parents, creating unique combinations of alleles in offspring.

What is the difference between oviparity and viviparity?

Oviparity involves laying eggs, while viviparity involves giving birth to live young.

What are reproductive cloning technologies?

Techniques used to create a genetically identical copy of an organism.

What is somatic cell nuclear transfer (SCNT)?

A cloning technique where the nucleus of a somatic cell is transferred to an egg cell from which the nucleus has been removed.

What are some applications of somatic cell nuclear transfer?

Applications include cloning endangered species, agricultural improvements, and producing genetically modified animals.

What are the complications associated with somatic cell nuclear transfer?

Complications include animal suffering, ethical concerns regarding human cloning, and premature aging in cloned animals.

What is embryo splitting?

A cloning technique where an embryo is split into two or more parts, each of which can develop into a genetically identical organism.

What are some applications of embryo splitting?

Applications include producing multiple offspring from a single embryo and enhancing genetic traits in livestock.

What complications are associated with embryo splitting?

Complications include alteration of embryos, reduced genetic diversity, and ethical concerns regarding research animals.

What is plant tissue culturing?

A technique used to grow plants from cells or tissues in a controlled environment.

What is a callus in plant tissue culturing?

A mass of undifferentiated plant cells that can develop into new plants.

What are some applications of plant tissue culturing?

Applications include mass propagation of plants, conservation of rare species, and genetic modification.

What is the process of plant cutting?

A method of vegetative propagation where a part of a plant (stem, leaf, or root) is cut and planted to grow a new plant.

What is the process of plant grafting?

A technique where tissues from one plant are inserted into those of another so that they grow together.

What is rootstock in plant grafting?

The part of the plant that provides the root system for the grafted plant.

What is a scion in plant grafting?

The part of the plant that is grafted onto the rootstock.

What are some applications of cutting and grafting?

Applications include producing disease-resistant plants, improving fruit quality, and propagating rare species.

What are some biological applications of plant cloning?

Applications include enhancing crop yields, preserving genetic diversity, and producing plants with desirable traits.

What is reproductive cloning?

A process that artificially produces genetically identical clones of an organism.

What are the stages of somatic cell nuclear transfer?

1. Enucleation, 2. Extraction, 3. Insertion, 4. Development.

What is the significance of Dolly the sheep?

Dolly was the first mammal cloned using SCNT in 1997.

How does embryo splitting relate to identical twins?

It is similar to the natural process of identical twin formation.

What is the ideal stage for embryo splitting?

When the cluster of cells is between 6-8 cells, as they are still totipotent.

What are the applications of embryo splitting in agriculture?

Used in combination with IVF to produce genetically identical offspring with desirable traits.

What are the applications of plant tissue culturing?

1. Agricultural research, 2. Cloning rare and endangered plants.

What is a plant cutting?

A fragment of a plant that can grow into a clone under the right conditions.

What is plant grafting?

Attaching the stem of one plant (scion) to another plant's root system (rootstock).

What are the benefits of grafting?

Provides cold tolerance, disease resistance, and increased productivity.

What are the biological implications of plant cloning?

Unrestrained cloning can reduce genetic diversity, making cloned populations more susceptible to disease and environmental changes.

What ethical implications must be considered in reproductive cloning?

The ethical concerns surrounding the manipulation of life and potential consequences of cloning.

What are abiotic factors?

Non-living properties of the environment, such as temperature, water, nutrient availability, and acidity.

What are biotic factors?

Living properties of the environment, including predator-prey interactions, plant-herbivore interactions, competition for resources, and symbiotic relationships.

What is the tolerance range of an organism?

The range of conditions within which an organism can thrive, survive, or not stay alive.

What are the two main categories of adaptations in hot environments?

Structural adaptations and physiological adaptations.

What is a structural adaptation?

Evolved modifications to an organism's physical structure.

What is a physiological adaptation?

Evolved modifications to an organism's internal functioning or metabolic processes.

What is a behavioral adaptation?

Evolved modifications to an organism's actions.

How do desert animals maximize heat loss?

By evolving insulation techniques and optimizing their surface area to volume ratio.

What is the significance of surface area to volume ratio (SA:V) in desert animals?

A high SA:V ratio allows for rapid heat release, while a low SA:V ratio helps resist temperature changes.

How do camels regulate their body temperature?

They have evolved optimal thickness of fur and fat to manage heat release.

What role does the circulatory system play in temperature balance for desert animals?

It helps release heat through dilation of blood vessels and increased blood flow to the skin.

What is evaporative cooling?

A method of heat loss through the evaporation of water, such as sweating and panting.

Why is evaporative cooling a challenge in arid environments?

It requires water, which can lead to dehydration.

How do desert mammals conserve water through urine?

They excrete concentrated urine that contains very little water.

How do reptiles and birds conserve water?

By excreting uric acid with other wastes in a semi-solid state.

What adaptation do desert animals have regarding their feces?

They have highly complex digestive systems that produce feces with low water content.

What are nocturnal behaviors?

Behaviors characterized by being active during the night and sleeping during the day.

What is the main challenge for endotherms in hot environments?

They must evolve effective strategies to release excess metabolic heat.

What advantage do ectotherms have in hot environments?

They can use energy not spent on metabolic heat for other processes, such as foraging.

What is the difference between endurers and evaders in desert animals?

Endurers are larger animals that do not avoid extreme temperatures, while evaders are smaller animals that modify their behaviors to avoid extreme temperatures.

How do desert animals avoid extreme temperatures?

Many desert animals seek shade or retreat to burrow systems to avoid heat absorption from solar radiation.

What behavioral adaptation do endurers exhibit during the hottest periods of the day?

Endurers tend towards inactivity to reduce metabolic heat production.

How do larger mammals like pigs and elephants cool down?

They wallow in mud or water baths, using evaporative cooling to remove heat from their bodies.

What is the significance of burrow systems for desert animals?

Burrow systems maintain cooler temperatures than the outside environment and rarely change during the hottest hours of the day.

What is nocturnal behavior in desert animals?

characterized by being active during the night and sleeping during the day, taking advantage of cooler nighttime temperatures.

What are the three main strategies plants use to survive in hot and dry environments?

1) Decrease heat intake, 2) Maximize water uptake, 3) Minimize water loss.

How do plants reduce their heat intake?

Plants may have light-colored or reflective leaves, leaves of low surface area, or vertically hanging leaves to minimize sun exposure.

What adaptation allows desert plants to access groundwater?

Many long-living desert plants have extensive deep root systems that can reach groundwater reserves.

How do some desert plants store water?

Some plants collect and store large amounts of water during the rainy season for use in the dry season, like baobabs and cacti.

What is the role of sunken stomata in desert plants?

Sunken stomata reduce water loss by creating pockets of humid air around the stomata, minimizing transpiration.

How do guard cells regulate stomata in desert plants?

Guard cells lose water during hot parts of the day, causing them to become flaccid and close the stomata to prevent gas exchange.

What is the purpose of having rolled or folded leaves in desert plants?

Rolled or folded leaves help maintain a humid environment around the leaf, reducing water loss.

What is the effect of increasing surface area on heat dissipation?

Increasing surface area allows for greater heat dissipation, as seen in practical activities comparing temperature drop in different containers.

How does the volume of water affect heat dissipation in practical experiments?

A full cup of water has a lower surface area to volume ratio compared to a quarter-filled cup, affecting the rate of temperature drop.

What is the significance of the surface area to volume ratio in heat regulation?

A greater surface area to volume ratio allows for more efficient heat dissipation, which is crucial for temperature regulation in both animals and plants.

What adaptations do desert plants have for minimizing water loss?

Desert plants may have reduced stomatal density, sunken stomata, or mechanisms to close stomata during the hottest parts of the day.

What is the purpose of regeneration after fire in desert plants?

allows certain desert plants to recover and thrive in environments that experience periodic fires.

What is the most influential abiotic factor in cold environments?

Extremely low temperatures.

What adaptations have animals evolved to survive in cold environments?

Structural, physiological, and behavioral adaptations.

What adaptations have plants evolved to survive in cold environments?

Structural and physiological adaptations.

How do low temperatures affect biological reactions?

They slow down or stop reactions required for life.

What impact do piercing winds have on organisms in cold environments?

They increase heat loss and exert strong pressures on plants.

Why is low availability of nutrients a challenge for organisms in cold environments?

It restricts macromolecule synthesis and overall growth rate.

How does precipitation as snow affect organisms?

It makes it difficult to obtain the liquid water required for survival.

What is one structural adaptation animals use for temperature balance?

Thick insulating layers of fur, plumage, or subdermal fat.

How does decreasing surface area to volume ratio help animals in cold environments?

It slows down heat release, helping maintain body temperature.