Unit 2 AOS 2 SAc

Question 1

What is viviparity in sexual reproduction, and how does it differ from other methods?

Answer 1

Viviparity (live-bearing) involves retaining fertilized eggs in or on a parent’s body. This derived mode of reproduction is thought to have evolved in response to various stresses on free-living larvae, such as predation, limited food resources, drying, cold temperatures, etc.

Question 2

What is oviparity in sexual reproduction, and which animals use this strategy?

Answer 2

Oviparity is the process of reproduction in which embryos develop inside eggs that are laid outside the mother’s body. Birds, most reptiles, and some fish reproduce this way.

Question 3

Why is genetic diversity important for the survival of a species or population?

Answer 3

Genetic diversity allows populations to adapt to changing environments and resist diseases, increasing their chances of survival and reducing the risk of extinction.

Question 4

What are the biological advantages of sexual reproduction?

Answer 4

Sexual reproduction increases genetic diversity, which enhances adaptability and resilience in offspring, enabling species to better survive environmental changes and potential diseases.

Question 5

What are the advantages and disadvantages of asexual reproduction?

Answer 5

Asexual reproduction is advantageous because it is fast and requires less energy, allowing rapid population growth. However, it produces genetically identical offspring, reducing adaptability to environmental changes.

Question 6

What is the purpose of reproductive cloning technology in plants?

Answer 6

Reproductive cloning in plants ensures consistency in traits like disease resistance, growth rates, and yield, making it useful in agriculture to produce high-quality crops.

Question 7

What are some reproductive cloning technologies used in animals?

Answer 7

Techniques like somatic cell nuclear transfer (SCNT) and embryo splitting are used in animals to create genetic copies, often for research, conservation, or agriculture purposes.

Question 8

What are the main ethical challenges associated with cloning?

Answer 8

Cloning raises ethical concerns, including animal welfare, premature aging of clones, potential human cloning, and reduced genetic diversity, along with the ethical treatment of research animals.

Question 9

What is somatic cell nuclear transfer (SCNT), and how is it used in cloning?

Answer 9

SCNT involves transferring the nucleus from a somatic cell into an enucleated egg, creating an embryo that can develop into a clone of the donor organism. This technique is widely used in research and animal cloning.

Question 10

How do animals adapt structurally, physiologically, and behaviorally to survive in hot environments?

Answer 10

Structural adaptations include insulation and high SA
ratio; physiological adaptations include evaporative cooling and concentrated urine; behavioral adaptations involve nocturnal activity and seeking shade to avoid extreme heat.

Question 11

What are some structural adaptations in plants for surviving hot environments?

Answer 11

Plants may have smaller, light-colored, or vertically oriented leaves to reduce heat absorption. Some also develop extensive root systems to maximize water intake and minimize water loss through stomata.

Question 12

How does torpor help animals survive in cold environments?

Answer 12

Torpor reduces metabolic rates and conserves energy, allowing animals to survive on limited resources during cold seasons. Examples include hibernation in mammals and brumation in reptiles.

Question 13

What is countercurrent circulation, and why is it beneficial in cold environments?

Answer 13

Countercurrent circulation transfers heat between adjacent blood vessels, helping animals conserve core body heat by warming blood returning to the heart, which is essential in cold habitats

Question 14

How does huddling behavior help animals conserve heat in cold environments?

Answer 14

By huddling, animals share body heat and minimize exposed surface area, which reduces heat loss and helps them stay warm, especially in species that live in groups.

Question 15

What is an apex predator, and what role does it play in its ecosystem?

Answer 15

An apex predator is at the top of its food chain with no natural predators. It helps control the population of prey species, maintaining balance within its ecosystem.

Question 16

What is a keystone species, and why is it essential to ecosystem health?

Answer 16

A keystone species has a disproportionately large impact on its environment. Its presence helps maintain biodiversity and ecological balance, as it influences the population and distribution of other species.

Question 17

What is vegetative propagation in asexual reproduction, and how is it beneficial?

Answer 17

Vegetative propagation is when new plants grow from cuttings or fragments of the parent plant, allowing for quick reproduction and spread, especially in stable environments.

Question 18

What is the function of stomata in plants, and how do they help with water regulation?

Answer 18

Stomata are openings on leaf surfaces that allow gas exchange and water regulation. Plants close stomata to reduce water loss during hot, dry conditions.

Question 19

How do Aboriginal and Torres Strait Islander perspectives enhance understanding of Australian ecosystems?

Answer 19

Indigenous knowledge includes observations of species’ adaptations and relationships, contributing valuable insights for managing biodiversity and ecosystem sustainability in Australia.

Question 20

How do plants adapt to survive in high-salinity environments?

Answer 20

Plants in salty environments develop structural adaptations, like specialized root systems, and physiological mechanisms to control salt intake and conserve fresh water, ensuring survival.

Question 21

What is parthenogenesis in asexual reproduction, and in which organisms does it occur?

Answer 21

Parthenogenesis is a form of asexual reproduction where a female produces offspring without fertilization by a male. It occurs in some plants, invertebrates, and certain reptiles and amphibians.

Question 22

How does a high surface area to volume (SA
) ratio help animals in hot environments?

Answer 22

A high SA
ratio increases the amount of body surface in contact with the air, which enhances heat dissipation and helps animals avoid overheating in hot climates.

Question 23

What is sporogenesis in asexual reproduction, and why is it effective for fungi and molds?

Answer 23

Sporogenesis is the production and release of spores, which can travel via air, water, or other organisms to colonize new areas, enabling fungi and molds to spread widely and reproduce quickly.

Question 24

What are biotic and abiotic factors, and why are they important for adaptations?

Answer 24

Biotic factors are living elements (like predators and food), and abiotic factors are nonliving elements (like temperature and water availability). They influence how organisms adapt to survive in specific environments.

Question 25

What is the purpose of insulation as a structural adaptation for animals in hot environments?

Answer 25

insulation helps larger animals stabilize body temperature, absorbing and releasing less heat, but limits heat release, which is ideal for those unable to escape high temperatures.

Question 26

How does SA ratio affect animals in hot environments?

Answer 26

Animals with a high surface area to volume (SA ) ratio have more contact with air, allowing for easier heat release. Elephants are an exception as they endure rather than release excess heat efficiently.

Question 27

What is vasodilation, and how does it help animals in hot environments?

Answer 27

Vasodilation is the widening of blood vessels near the skin to increase blood flow, allowing heat to escape from the body and cool the animal.

Question 28

Name a behavioral adaptation animals use to cope with extreme heat.

Answer 28

Animals may evade the heat by using burrows or being nocturnal or endure it by staying inactive during the hottest parts of the day or covering their backs with mud.

Question 29

What are two structural adaptations of plants to reduce heat uptake?

Answer 29

Plants have lightly colored leaves with reduced surface area and orient leaves vertically to reduce direct sun exposure and heat absorption.

Question 30

How do plants increase water uptake in arid environments?

Answer 30

They use deep root systems to access groundwater or shallow, spread-out roots to absorb surface water quickly after rainfall.

Question 31

Why is insulation important as a structural adaptation in cold environments?

Answer 31

Thick skin, fur, or fat acts as insulation, trapping body heat and protecting animals from the cold by reducing heat loss.

Question 32

What is torpor, and how does it benefit animals in cold environments?

Answer 32

Torpor is a state of reduced metabolic activity, like hibernation in mammals or brumation in reptiles, allowing animals to conserve energy and survive cold periods.

Question 33

How does countercurrent circulation help animals in cold environments?

Answer 33

This adaptation allows warm blood from the core to transfer heat to cooler blood returning from the extremities, maintaining a stable core temperature.

Question 34

Give an example of a behavioral adaptation animals use in cold environments to conserve heat.

Answer 34

Animals may curl up to reduce surface area exposure, huddle with others, or seek shelter in burrows to retain body heat.

Question 35

What are interdependencies between species, and why are they important?

Answer 35

Interdependencies, such as mutualism and competition, describe interactions where species rely on each other for survival, maintaining ecosystem balance and stability.

Question 36

1. What are the two key structural adaptations used by animals to thermoregulate in hot environments ?

Answer 36

Two key structural adaptations used by animals to thermoregulate in hot environments are large surface area to volume ratio (e.g., large ears in elephants) and light-coloured fur or skin to reflect sunlight.

Question 37

2. What are the two key behavioural adaptations used by animals to thermoregulate in hot environments?

Answer 37

Two key behavioural adaptations used by animals to thermoregulate in hot environments are seeking shade or burrowing during the hottest parts of the day and changing activity patterns, such as being nocturnal. – Evading, and Enduring

Question 38

3. What are two physiological adaptations used by animals to maintain water balance?

Answer 38

Two physiological adaptations used by animals to maintain water balance are concentrated urine to reduce water loss and the ability to tolerate dehydration

Question 39

4. What are two structural adaptations used by plants to reduce heat exposure?

Answer 39

Two structural adaptations used by plants to reduce heat exposure are small or narrow leaves and reflective or waxy leaf surfaces to reduce heat absorption.

Question 40

1. What are two structural and/or physiological adaptations used by plants to increase water uptake and decrease water loss?

Answer 40

Two structural or physiological adaptations used by plants to increase water uptake and decrease water loss are deep root systems to access underground water and stomatal control to limit water loss through transpiration.