What is plasticity?5 answersPlasticity refers to the ability of a material or organism to change its structure or function in response to external stimuli or environmental factors. In materials science, plasticity is the ability of a solid to deform under loads and retain some deformation after the load is removed. In biology, phenotypic plasticity allows a single genotype to produce different phenotypes based on environmental conditions, influencing fitness and survival. Neuroplasticity, observed in the brain, involves the ability of neural networks to reorganize and form new connections, impacting learning, memory, and recovery from injuries. In ecological studies, phenotypic plasticity can evolve in response to variable environments, affecting life history traits and population dynamics, showcasing an eco-evolutionary feedback loop. Additionally, the neuromuscular system exhibits adaptive plasticity, enabling reorganization based on experiences and motor activities.
What is lineage plasticity?4 answersLineage plasticity refers to the ability of cells to change their phenotype and acquire a different molecular and/or histologic identity. It is a dynamic process controlled by transcriptional and epigenetic dysregulation, rather than solely genetic changes within the tumor. Lineage plasticity is a hallmark of cancer and is associated with cancer progression, therapy resistance, metastasis, dysregulated metabolism, and immune evasion. In prostate cancer, lineage plasticity allows tumor cells to switch between different developmental pathways, such as luminal and basal phenotypes, under the pressures of therapy. In breast cancer, luminal-to-basal plasticity is responsible for the emergence of basal-like characteristics in tumors expressing lower levels of estrogen receptor (ER). Lineage plasticity is a nongenetic, potentially reversible transcriptional adaptation, but oncogenic genetic mutations can drive elevated lineage plasticity in cancer cells. Understanding lineage plasticity is crucial for developing strategies to target and treat highly plastic tumors.
What is the potential pitfalls of overemphasis on group work engagement?5 answersOveremphasis on group work engagement can lead to potential pitfalls. It can inhibit the enjoyment and skill in shared learning, as well as promote competitive learning and anxieties about individual students' academic achievements. If students cannot see the objective of group work, are unsure of what is expected of them, or believe the assessment methods are invalid or unfair, tensions can emerge and the educational benefits of group work are reduced. In addition, poorly managed group work can lead to dysfunction, interpersonal conflicts, and uneven distributions of labor among group members. These issues can hamper overall student success, especially in engineering fundamentals courses where advanced students may dominate the group work, leaving other students falling behind. Therefore, careful planning, clear assessment guidelines, and effective group management processes are essential to avoid these pitfalls and ensure the success of group work.
What are the ethical concerns in enhancing plasticity (e.g., drugs, devices) in rehabilitation and learning?5 answersEnhancing plasticity in rehabilitation and learning raises ethical concerns regarding safety, compromised character, distributive justice, and coercion. These concerns apply to both adults and children, as well as to soldiers who may choose to enhance their abilities. Prohibition of enhancements is not seen as a viable option, and instead, cultural norms, clinical practice, and public policy discussions are needed to address these concerns. In the context of stroke recovery, drug therapies and stem cell therapy show promise in enhancing functional recovery. However, the efficacy of these treatments in severely affected patients and those with massive brain lesions needs further investigation. Additionally, the use of biomaterials that resemble lesioned brain structures may hold potential for increasing functional reconnections within host tissue. Overall, the ethical concerns surrounding plasticity enhancement in rehabilitation and learning require careful consideration and ongoing research.
What are the downsides of neuroplasticity?5 answersNeuroplasticity, the brain's ability to adapt and change, can have downsides. One downside is the development of pain and dysfunction in organs controlled by the autonomic nervous system after spinal cord injury (SCI). This occurs due to structural neuroplasticity, which involves the growth of new synaptic connections in response to injury. Another downside is the negative consequences that can arise from therapies that directly stimulate nerve growth, such as increased pain and dysfunction. Additionally, long periods of stress can lead to structural and excitatory changes associated with anxiety and depression. Drugs of abuse can also cause long-lasting changes in reward-related circuits, resulting in addiction. These forms of long-term plasticity in the brain require changes in gene expression and can lead to sensitization or desensitization of neural circuits.
What is high plasticity in plants?3 answersHigh plasticity in plants refers to the ability of an organism to change its phenotype in response to different environments. It is a quantitative trait that allows plants to adapt to rapid changes in their surroundings. Plasticity can provide a fitness advantage and mitigate negative effects due to environmental perturbations. The genetic basis of plasticity in plants is not fully understood, but recent advances in understanding the genetic architecture have been made. Computational approaches and theories are being developed to uncover the causal genes for plasticity and their role in plant fitness and evolution. Plants have remarkable plasticity due to their vast genetic potential, which interacts with external factors and developmental signals to govern development and adaptation to changing environments. Plasticity in plants can be advantageous for increasing environmental tolerance, but not all plastic responses are adaptive. Some plastic changes may simply reflect passive responses to the environment or be by-products of adaptive plastic responses in other traits. Flower longevity in plants is a highly plastic trait that is optimized to balance reproductive success against the costs of flower maintenance. It is influenced by pollination success and can vary within and among populations. Alpine populations of plants show higher plasticity in flower longevity compared to populations from lower elevations, which may be advantageous in their unpredictable pollination environment. Invasive plant species display high trait plasticity, particularly in response to nutrient availability. This plasticity can influence plant performance and fitness.