Adaptation to Biological Stressors: (Mal)Nutrition

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What condition is associated with the consumption of unmilled rice?

Rickets

Beriberi (correct)

Anemia

Scurvy

Which of the following symptoms is NOT associated with Scurvy?

Severe bruising

Bulging eyes

Swollen, bloody gums

Poorly mineralized bones (correct)

What role does Vitamin D play in the body?

Stimulates calcium absorption (correct)

Absorbs iron from diet

Stimulates protein synthesis

Regulates thyroid hormone

Which mineral deficiency leads to the development of goiters?

Iodine Signup and view all the answers

What is a common symptom of iron deficiency anemia?

Fatigue Signup and view all the answers

Which group of individuals is most likely to experience Scurvy today?

Low income populations with poor diet Signup and view all the answers

What causes lactose intolerance in mature mammals?

Decreased lactase activity Signup and view all the answers

Which vitamin is crucial for collagen production?

Vitamin C Signup and view all the answers

What is a typical sign of rickets, commonly caused by Vitamin D deficiency?

Weakening of bones Signup and view all the answers

What role do electrolytes play in the body?

Carry electric charge and facilitate bodily functions Signup and view all the answers

What type of malnutrition is characterized by neither an excess nor a complete lack of food but rather an unbalanced diet?

Chronic micronutrient malnutrition Signup and view all the answers

Which nutrient is classified as a macronutrient that can be broken down into building blocks?

Proteins Signup and view all the answers

In the context of protein deficiency, what happens when there is a lack of any essential amino acid?

It leads to general protein deficiency Signup and view all the answers

What is the primary short-term energy source used by the body during periods of total undernutrition?

Glycogen Signup and view all the answers

Which historical diet is noted for reducing the risk of essential amino acid deficiencies due to its variety?

Mesoamerican Diet Signup and view all the answers

What type of malnutrition results from excessive caloric intake leading to health risks?

Obesity Signup and view all the answers

Which essential component of proteins must be consumed because the body cannot produce them?

Essential amino acids Signup and view all the answers

Which type of malnutrition is likely to result when food intake is completely absent?

Protein-calorie malnutrition Signup and view all the answers

What role does fat play in the body's energy reserves during periods of prolonged undernutrition?

It serves as a long-term energy store Signup and view all the answers

Which of the following is NOT classified as a macronutrient?

Vitamins Signup and view all the answers

What is a consequence of protein breakdown after glycogen and fat reserves are depleted?

Muscle wasting and impact on the immune system Signup and view all the answers

Which condition is characterized by protein deficiency while maintaining adequate intake of other nutrients?

Kwashiorkor Signup and view all the answers

What growth disruption is specifically associated with a reduction in linear growth?

Stunting Signup and view all the answers

Which vitamin deficiency can lead to rhodopsin protein deficiency resulting in 'night blindness'?

Vitamin A Signup and view all the answers

How does severe malnutrition in all categories, characterized by dehydration and emaciation, present?

Marasmus Signup and view all the answers

What physiological change can occur due to inadequate protein that affects bone growth?

Harris lines formation Signup and view all the answers

What is a common misconception about overnutrition during childhood?

It solely occurs in developed countries. Signup and view all the answers

Which vitamin plays a critical role in carbohydrate and protein metabolism and its deficiency can cause issues in high-carb diets?

Vitamin B1 Signup and view all the answers

What is a primary risk associated with protein deficiency in children?

Increased risk of poor cognitive development. Signup and view all the answers

What mechanism allows the central nervous and reproductive systems to be spared during periods of starvation?

Thrifty genotype advantage Signup and view all the answers

What primarily determines lactase persistence in individuals?

Presence of specific alleles in the LCT gene Signup and view all the answers

Which of the following statements regarding lactase persistence is true?

The severity of symptoms varies among carriers of associated alleles. Signup and view all the answers

What evidence supports the theory of convergent evolution in lactase persistence?

Distinct SNPs involved due to strong selective pressure Signup and view all the answers

What was one of the primary cultural adaptations associated with lactase persistence?

Animal domestication and adult milk consumption Signup and view all the answers

Which of the following is NOT a potential drawback of lactose intolerance?

Increased risk of severe allergic reactions Signup and view all the answers

What aspect does Tinbergen's Four Questions focus on regarding lactase persistence?

Variations in genetic adaptations to milk consumption Signup and view all the answers

What is a key adaptive benefit of milk consumption for pastoral populations?

Availability of carbohydrates, fats, calcium, and protein Signup and view all the answers

Which of the following best describes the relationship between lactase persistence and cultural practices?

Both gene co-evolution and cultural adaptations influenced lactase persistence. Signup and view all the answers

How has selective pressure influenced the variation in lactase persistence over the past thousands of years?

It has led to diverse genetic adaptations in response to milk consumption. Signup and view all the answers

What does the term SNP refer to in the context of lactase persistence?

Single nucleotide polymorphism Signup and view all the answers

Study Notes

Adaptation to Biological Stressors, Part 1: (Mal)Nutrition

The presentation covers malnutrition and nutrition, and infectious diseases.
Malnutrition is categorized into three types, including too little, too much, and poorly balanced.
Too little malnutrition, specifically protein-calorie malnutrition (PCM), involves periods of starvation, lack of food, and insufficient quantity/quality.
Too much malnutrition, or overabundance, is also discussed..
Poorly balanced malnutrition specifically covers chronic micronutrient malnutrition, describing imbalances in the diet.
Obesity is now killing more people than malnutrition, according to a landmark study.
Maps show global prevalence rates of undernourishment and obesity, illustrating their distribution around the world.
Different regions on the maps indicated various percentages of undernourishment and obesity in their populations.

Nutrients vs Food

The concept of distinguishing nutrients from food.
Visual presentation examples of foods which visually differentiated nutrients from food

Nutrients

Nutrients are categorized as energy and materials.
Macronutrients: Carbohydrates, proteins, and fats (lipids).
Micronutrients: Vitamins and minerals.

Protein

Protein structure is composed of amino acids joined together, forming peptides and polypeptides.
Protein function is highly variable.
Proteins are broken down into amino acids.
Some amino acids are essential, meaning they must be consumed, while others are nonessential, meaning they can be created.
Reliance on a single plant source can cause essential amino acid deficiencies.

Protein Quality of Foods

Mesoamerican diets, including Maya and Aztec, and modern Mexican and Central American diets, utilized beans and maize (corn).
Using plants that have the complete range of amino acids reduced the risk of deficiencies.
A variety of foods were shown to help with necessary amino acid intake.

Protein Deficiency

Maps showed locations and prevalence amounts of stunting, likely due to protein deficiency
Locations specific to Africa, Asia, and other areas displayed the problem of stunting.

Energy Reserves

Three forms of energy used by the body: glycogen, fat, and protein.
Glycogen is a short-term, readily available energy source stored in the liver and muscles.
Fat is a long-term energy reserve stored in the body.
Protein is also used for energy when glycogen and fat reserves are depleted.

Biology of Deficiency

When glycogen and fat reserves are depleted, protein breakdown begins in muscles.
Children are particularly vulnerable due to growth needs.
Kwashiorkor and Marasmus are consequences of protein deficiency and severe malnutrition, respectively.
Kwashiorkor is characterized by edema (swelling) and an enlarged liver due to inadequate protein intake.
Marasmus is severe malnutrition encompassing all categories including dehydration and emaciation.

Growth Disruptions

Children's growth patterns tend to be similar, requiring protein for proper development.
Stunting refers to reduced linear growth, while wasting involves low weight for height.
Harris lines appear on bones during periods of physiological stress, indicating slowed growth.

Overnutrition

Overnutrition involves accelerated growth during childhood, early menstrual cycles onset and decelerated adolescent growth.
This is a global issue, even in "developed" nations.

Can We Adapt?

Human beings, compared to other mammals, exhibit the ability to adjust to short-term issues such as starvation.
The central nervous and reproductive systems are often spared.
"Thrifty genotype" refers to the ability to withstand periods of starvation.

Micronutrient Deficiencies

Vitamin and mineral deficiencies arise due to poor diets and limited food resources.

Vitamin A (Retinol)

Derived from beta-carotene (stored in the liver).
Deficiency results in rhodopsin protein deficiency (night blindness), dry hair, scaly skin, and brittle nails.
Maps highlighted the geographic distribution of vitamin A deficiencies.

Vitamin B1 (Thiamine)

Crucial for carbohydrate and protein metabolism.
Deficiency causes issues with neurotransmitters and beriberi.
Beriberi presents in wet or dry forms affecting the heart and nervous system or muscles respectively.
MIlked rice has reduced thiamine compared to unmilled rice.

Vitamin C (Ascorbic Acid)

Essential for collagen production and crucial for sailors embarking on long voyages, as deficiencies cause scurvy.
Scurvy presents with signs including swollen/bloody gums, loose teeth, bulging eyes, and severe bruising.

Vitamin D (Calcitriol)

Stimulates calcium absorption in the small intestine.
Deficiency leads to osteomalacia (poorly mineralized bones) and rickets in children.

Electrolytes

Electrolytes are minerals with electric charges crucial for bodily tissues and fluids.
This section identifies four important electrolytes - magnesium, calcium, sodium, and potassium.

Iron Deficiency

Iron deficiency, a common nutritional issue, leads to anemia, causing fatigue, neurological impairment, sore muscles, and decreased immunity.
A global map displayed the prevalence of iron deficiency, specifically Anemia in children.
Anemia is associated with low haemoglobin levels, and is one of the primary ways in which iron deficiency manifests itself in children's health statistics.

Iodine

Iodine is needed by the body to synthesize thyroid hormones.
Iodine regulates development, metabolism, and thyroid function.
Deficiency can lead to goiters and hypothyroidism.
Iodine rich foods were shown on a list of certain foods.

Lactose Tolerance

Lactase activity decreases with age, impacting lactose digestion.
Lactase persistence is genetic, and its variation across populations is described.
Genetic variation explains why some populations retain the ability to digest lactose into adulthood while others do not.
Maps provided data on the prevalence of lactose tolerance across the globe.
Co-evolution suggests a connection between genes and cultural practices, in this case, pastoralism and the consumption of animal milk.
This suggests that the ability to consume adult milk products is linked to shared cultural traits which involved pastoral practices relating to milk and animal-raising.
Advantages of the consumption of milk include protein, calcium, and fats, while disadvantages concern lactose intolerance, diarrhea, and water loss.

Tinbergen's Four Questions

This section poses questions regarding why lactase persistence differs among populations and how they can be related to the four key questions posed by Tinbergen.

Why would human biologists criticize these claims?

This section raises the concerns of human biologists regarding the use of genetic claims to justify racial purity ideas.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz explores the critical aspects of malnutrition, categorizing it into three main types: too little, too much, and poorly balanced. It highlights the impacts of various forms of malnutrition on health, including protein-calorie malnutrition and obesity. Additionally, the quiz discusses global prevalence rates and differentiates between nutrients and food.