Adaptations, Diversity, and Reproduction — Vocabulary Flashcards (Video Notes)

Vocabulary flashcards covering key terms related to adaptations, ecological relationships, energy flow, reproduction, cloning, biotic/abiotic factors, and human impacts as described in the video notes.

Allele

A variant form of a gene that can influence how a trait is expressed.

Genetic Diversity

The variety of alleles within a population; increased by mutations, sexual reproduction, and gene flow; decreased by asexual reproduction, bottlenecks, and founder effects; maintained by large populations, ongoing gene flow, and balancing selection.

Mutation

A random change in DNA that can create new alleles.

Gene Flow

Movement of individuals and their genes between populations.

Population Bottleneck

A drastic reduction in population size that reduces the allele pool and genetic diversity.

Founder Effect

A small group starts a new population with a limited set of alleles.

Asexual Reproduction

Reproduction without gamete fusion, producing genetically identical offspring.

Balancing Selection

Natural selection that maintains multiple alleles in a population.

Structural Adaptation

Physical features of an organism that help regulate temperature, access food, or move efficiently.

Behavioral Adaptation

Actions or patterns of activity that aid survival (e.g., avoiding predators, finding food or mates).

Physiological Adaptation

Internal body processes that enable survival in harsh conditions or improve efficiency.

Symbiosis

A relationship between two or more species where at least one benefits or is harmed.

Parasitism

One species benefits at the expense of the other; a parasite lives on or in the host.

Mutualism

A relationship where both species benefit and neither is harmed.

Commensalism

One species benefits while the other is neither harmed nor helped.

Amensalism

One species is harmed while the other is unaffected.

Keystone Species

A species with a disproportionate impact on ecosystem diversity, population sizes, and structure.

Food Chain

A linear sequence showing energy transfer from one organism to another; about 10% of energy is transferred to the next level, with 90% lost as heat.

Ten Percent Rule

Rough rule that only ~10% of energy is passed to the next trophic level; the rest is lost as heat.

Primary Producers

Organisms that produce energy for the ecosystem (e.g., plants, algae).

Primary Consumers

First-order consumers that eat producers.

Secondary Consumers

Eat primary consumers; second-order consumers.

Tertiary Consumers

Eat secondary consumers; third-order consumers.

Quaternary Consumers

Fourth-order consumers at the top of the food chain.

Food Web

A network of feeding relationships showing energy and matter flow in an ecosystem.

Meiosis

Cell division that produces genetically varied gametes with half the chromosome number.

Gametes

Reproductive cells (sperm and egg) carrying half the normal number of chromosomes.

Fertilisation

Fusion of two gametes to form a zygote; creates genetic variation through random combination.

Zygote

The fertilised egg; the first cell of a new organism.

Internal Fertilisation

Fertilisation occurs inside the female’s body; fewer gametes are needed and success rates are higher.

External Fertilisation

Fertilisation occurs outside the body (usually in water); many gametes are released and success rates are lower.

Embryo Splitting

A cloning method where a fertilised embryo is divided to form two or more genetically identical embryos.

Nuclear Transfer

A cloning method where a donor nucleus is transferred into an enucleated egg to create a genetically identical embryo.

Cloning

Reproduction that produces genetically identical offspring; can involve embryo splitting or nuclear transfer.

Reproductive Cloning

Cloning aimed at producing genetically identical organisms for reproduction; has advantages (uniformity, conservation) and disadvantages (low success, ethical concerns, reduced diversity).

Embryo Transfer

Transferring embryos into surrogate mothers during cloning or assisted reproduction.

Biotic

Living factors in the environment that influence organisms and their interactions.

Abiotic

Non-living environmental factors that set physical limits for survival.

Habitat Destruction

The loss or destruction of a habitat, reducing resources and living space for species.

Pollution

Contamination of the environment that harms living organisms and ecosystems.

Climate Change

Long-term changes in climate patterns that affect distributions, survival, and interactions.

Overexploitation

Excessive use of natural resources leading to declines in populations.

Invasive Species

Non-native species that spread rapidly and harm native ecosystems.

Conservation

Efforts to protect and manage biodiversity to prevent extinction and decline.

Habitat Restoration

Rehabilitating damaged ecosystems to restore their natural structure and function.

Legal Protection

Laws and regulations that protect species and habitats from harm.