Podcast
Questions and Answers
What primarily affects oral health rather than aging itself?
What primarily affects oral health rather than aging itself?
What phenomenon describes normal diploid cells ceasing to divide after a certain number of divisions?
What phenomenon describes normal diploid cells ceasing to divide after a certain number of divisions?
In the context of appetite changes, which statement is correct regarding hunger and satiety cues?
In the context of appetite changes, which statement is correct regarding hunger and satiety cues?
What does the Hayflick Limit refer to in terms of cellular aging?
What does the Hayflick Limit refer to in terms of cellular aging?
Signup and view all the answers
What is suggested to be a better definition of old age than chronological age?
What is suggested to be a better definition of old age than chronological age?
Signup and view all the answers
Which theory of aging focuses on the buildup of unstable oxygen compounds?
Which theory of aging focuses on the buildup of unstable oxygen compounds?
Signup and view all the answers
Telomere shortening occurs due to what process?
Telomere shortening occurs due to what process?
Signup and view all the answers
What is a characteristic of the programmed aging theory?
What is a characteristic of the programmed aging theory?
Signup and view all the answers
What happens to appetite-regulating mechanisms as one ages?
What happens to appetite-regulating mechanisms as one ages?
Signup and view all the answers
What is a consequence of dehydration in older adults?
What is a consequence of dehydration in older adults?
Signup and view all the answers
Which age range is classified as 'young old' according to the U.S. Census Bureau?
Which age range is classified as 'young old' according to the U.S. Census Bureau?
Signup and view all the answers
What is the primary physiological change associated with aging that affects muscle mass?
What is the primary physiological change associated with aging that affects muscle mass?
Signup and view all the answers
What defines life expectancy in a population cohort?
What defines life expectancy in a population cohort?
Signup and view all the answers
What type of changes does cellular senescence involve?
What type of changes does cellular senescence involve?
Signup and view all the answers
How does body composition typically change with aging?
How does body composition typically change with aging?
Signup and view all the answers
Which scale is used to assess Activities of Daily Living to determine independent living ability?
Which scale is used to assess Activities of Daily Living to determine independent living ability?
Signup and view all the answers
Which statement best describes the human life span as projected?
Which statement best describes the human life span as projected?
Signup and view all the answers
What major global factor contributes to the increase in life expectancy?
What major global factor contributes to the increase in life expectancy?
Signup and view all the answers
What role do hormones play in changing body composition with aging?
What role do hormones play in changing body composition with aging?
Signup and view all the answers
Which sensory change is frequently reported to decline with age?
Which sensory change is frequently reported to decline with age?
Signup and view all the answers
Study Notes
Biology of Ageing - Lecture 22
- Ageing is defined by methods using functional status, rather than chronological age
- Methods include the Katz ADL scale, used to measure daily living activities and independence
- The Katz ADL scale assesses abilities such as bathing, dressing, toileting, transferring, continence, and feeding
- Scores range from 0 (very dependent) to 6 (high independent)
- Defining old age, there's no universally agreed-upon age; ranges and categories exist (e.g., 51-70 years, >70 years, 65 years (Medicare eligibility), 60 years, World Health Organization categories) but functional and various other assessments are important
- The US Census Bureau uses different age categories (young old: 65-74 years, aged: 75-84 years, oldest old: 85+)
- Life expectancy is the average number of years a person is expected to live in a population cohort. It's typically reported as life expectancy from birth
- Life span is the maximum number of years a person can live. Human life span is projected between 110-120 years
- Improvements in life expectancy are largely due to fewer deaths from cardiovascular diseases (CVD), stroke, and accidents. The same is true as someone ages but mortality rates associated with different diseases are important to distinguish
- Physiological changes with ageing include changes in body composition, leading to a loss of physical resilience. Fat-free mass (bone, muscle, water) decreases, with muscle loss being the most prominent (sarcopenia)
- A rise in body fat mass, and a decrease in overall body weight, are also common
- Factors that influence body composition changes with ageing include physical activity, hormones, food intake, and lower metabolism
- Sensual awareness, such as taste and smell, can be affected by ageing; declining taste and smell can also be present due to disease or medication
- Oral health alongside changes in taste and smell can also include issues with teeth loss caused by factors unrelated to aging (GI secretions, skeletal system, mucosal membrane, muscle in the mouth), olfactory neurons and taste buds
- Appetite and thirst regulation mechanisms weaken with age, leading to potential undernutrition and an increase in the likelihood of dehydration
- Tools like the Mini Nutritional Assessment (MNA) are used in clinical contexts to screen and assess nutritional status in older adults
- Cellular senescence is the process of cells accumulating changes in structure and disrupting metabolism, thus leading to deterioration over time
- Hayflick Limit: normal somatic cells have a limited number of cell divisions. Cells stop dividing after about 50-60 divisions in vitro
- Telomeres, repetitive nucleotide sequences at the ends of chromosomes, protect the chromosome from deterioration but shorten with each cell division, thus making an important factor in cell aging
Theories of Aging
-
Programmed aging (e.g., Hayflick Limit, Cellular senescence, Molecular Clock Theory - Telomere shortening)
- Hayflick Limit: All cells have a limited number of divisions
- Cellular senescence: Cells stop dividing after a certain number of divisions
- Telomere shortening: Telomeres shorten upon each cell division leading to cellular ageing
-
Wear and tear theory (e.g., Free Radical Theory)
- Free radical theory: Build-up of unstable oxygen compounds (ROS) leading to damage in tissues and cells over time, leading to cellular ageing
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Explore the various methods used to define and assess ageing, focusing on the Katz ADL scale for measuring functional status. Understand the classifications of old age and how life expectancy and lifespan are determined. This lecture delves into the complexities of ageing beyond just chronological measures.
