L13: Physiological Aging in Adulthood

Question 1

Ageing

Answer 1

The time-related detoriation of physiological functions

Question 2

Senescence

Answer 2

The ageing of cells and the organism as a whole. Biological ageing is inevitable

Question 3

How does ageing manifest at the molecular level?

Answer 3

DNA lesions and the shortening of chromosomes’ telomeres during replication

Question 4

What proportion of New Zealand’s population will be 65+ by 2050

Answer 4

27%

Question 5

Define sarcopenia, osteopenia, and dynapenia

Answer 5

Sarcopenia: Loss of muscle
Osteopenia: Loss of bone
Dynapenia: Loss of strength

All are age-related

Question 6

How much muscle mass is lost every decade after 30?

Answer 6

3 - 8%

Question 7

What muscle type experiences the most atrophy with age and disuse?

Answer 7

Type 2

Question 8

Fibrosis

Answer 8

The scarring and thickening of muscle fibres, which makes them thicker, weaker, and more susceptible to injury

Question 9

If elderly people’s hearts tend to be larger than younger people’s hearts, why are they less healthy?

Answer 9

Elderly people’s hearts are likely to have a greater amount of fibrosis. Even though they appear bigger, they are weaker

Question 10

Brown adipose tissue

Answer 10

Generates heat. Decreases with age which is why elderly people tend to be colder

Question 11

White adipose tissue

Answer 11

Involved in lipid storage and immuno-endocrine responses

Question 12

Why do elderly people tend to have more visceral fat?

Answer 12

Due to changes in gondal hormones

Question 13

When does bone mass and density begin to decline? How does it differ between males and females?

Answer 13

At 50, espically for females going through menopause due to the drop in estrogen

Question 14

What are osteoclasts and osteoblasts responisble for?

Answer 14

Osteoclasts: Breaking down old and weak bone
Osteoblast: Building new and strong bone

Question 15

How does estrogen affect the balence of osteoclasts and osteoblasts?

Answer 15

Estrogen regulates bone metabolism. Lack of estrogen causes the proportion of osteoclasts to be greater than the proportion of osteoblasts

Question 16

What proportion of myocytes are lost between 30 - 70?

Answer 16

35%

Question 17

How does the ageing heart compensate for the loss of myocytes?

Answer 17

The heart increases the volume of remaining myocytes, causing hypertrophy but also stiffer walls

Question 18

Why are elderly people more prone to arrythymias?

Answer 18

Loss of cells in the SA node

Question 19

What proportion of people over 75 have hypertension?

Answer 19

> 80% for both males and females

Question 20

What proportion of brain mass if lost every decade after 40? How does this change in older adults?

Answer 20

5% after 40

20% in older adults

Question 21

What 3 parts of the central nervous system change with age?

Answer 21

1. Gret matter
2. Neurons
3. Synapses

Question 22

What are 3 effects to behaviour and neurological functioning with age?

Answer 22

1. Slower reasoning
2. Slower problem solving
3. Reduced perceptual speed

Elderly people are still intelligent. They’re just slower

Question 23

Why do elderly people tend to struggle with memory?

Answer 23

Atrophy with the hippocampus

Question 24

Why do elderly people struggle with thermoregulation?

Answer 24

Reduced skin blood flow and sweat gland output