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Read the following passage carefully and choose the best answer to each question out of the four alternatives.

The rate of biodiversity loss is alarming, with recent estimates showing that species extinctions are currently 10 to 100 times higher than the natural baseline. This is largely due to human activities like deforestation, habitat fragmentation, and climate change. This loss threatens essential ecosystem services, including pollination, soil fertility, and water purification, with direct consequences for human health. For example, the degradation of wetlands, which filter freshwater, has led to a 35% decline in global wetland coverage since 1970, thus increasing waterborne diseases and reducing water availability for over 2 billion people.

Biodiversity loss and ecosystem degradation are becoming major health concerns. When ecosystems are disrupted, services like clean air, water, and food can be affected. Additionally, we lose valuable natural resources – like plants and animals – that may hold untapped benefits for health and medicine.

Biodiversity serves as the foundation of healthy, sustainable food systems. It directly influences the availability and nutritional value of food, as a diverse range of plant and animal species, ecosystems, and genetic resources contribute to healthier, more resilient food production. Access to enough nutritious and varied food is a fundamental determinant of health.

Nutrition and biodiversity are interconnected at various levels, from ecosystems that provide food to the genetic diversity within species. This diversity affects the nutritional composition of food, including micronutrient availability. Healthy diets with adequate nutrient intake depend on high biodiversity.

Read the following passage carefully and choose the best answer to each question out of the four alternatives.

The rate of biodiversity loss is alarming, with recent estimates showing that species extinctions are currently 10 to 100 times higher than the natural baseline. This is largely due to human activities like deforestation, habitat fragmentation, and climate change. This loss threatens essential ecosystem services, including pollination, soil fertility, and water purification, with direct consequences for human health. For example, the degradation of wetlands, which filter freshwater, has led to a 35% decline in global wetland coverage since 1970, thus increasing waterborne diseases and reducing water availability for over 2 billion people.

Biodiversity loss and ecosystem degradation are becoming major health concerns. When ecosystems are disrupted, services like clean air, water, and food can be affected. Additionally, we lose valuable natural resources – like plants and animals – that may hold untapped benefits for health and medicine.

Biodiversity serves as the foundation of healthy, sustainable food systems. It directly influences the availability and nutritional value of food, as a diverse range of plant and animal species, ecosystems, and genetic resources contribute to healthier, more resilient food production. Access to enough nutritious and varied food is a fundamental determinant of health.

Nutrition and biodiversity are interconnected at various levels, from ecosystems that provide food to the genetic diversity within species. This diversity affects the nutritional composition of food, including micronutrient availability. Healthy diets with adequate nutrient intake depend on high biodiversity.

Read the given passage carefully and answer the questions that follow.

Until about five years ago, the very idea that peptide hormones might be made anywhere in the brain besides the hypothalamus was astounding. Peptide hormones, scientists thought, were made by endocrine glands and the hypothalamus was thought to be the brains’ only endocrine gland. What is more, because peptide hormones cannot cross the blood-brain barrier, researchers believed that they never got to any part of the brain other than the hypothalamus, where they were simply produced and then released into the bloodstream. But these beliefs about peptide hormones were questioned as laboratory after laboratory found that antiserums to peptide hormones, when injected into the brain, bind in places other than the hypothalamus, indicating that either the hormones or substances that cross-react with the antiserums are present. The immunological method of detecting peptide hormones by means of antiserums, however, is imprecise. Cross-reactions are possible and this method cannot determine whether the substances detected by the antiserums really are the hormones, or merely close relatives. Furthermore, this method cannot be used to determine the location in the body where the detected substances are actually produced. New techniques of molecular biology, however, provide a way to answer these questions. It is possible to make specific complementary DNA’s (cDNA’s) that can serve as molecular probes to seek out the messenger RNA’s (mRNA’s) of the peptide hormones.

Read the given passage carefully and answer the questions that follow.

Until about five years ago, the very idea that peptide hormones might be made anywhere in the brain besides the hypothalamus was astounding. Peptide hormones, scientists thought, were made by endocrine glands and the hypothalamus was thought to be the brains’ only endocrine gland. What is more, because peptide hormones cannot cross the blood-brain barrier, researchers believed that they never got to any part of the brain other than the hypothalamus, where they were simply produced and then released into the bloodstream. But these beliefs about peptide hormones were questioned as laboratory after laboratory found that antiserums to peptide hormones, when injected into the brain, bind in places other than the hypothalamus, indicating that either the hormones or substances that cross-react with the antiserums are present. The immunological method of detecting peptide hormones by means of antiserums, however, is imprecise. Cross-reactions are possible and this method cannot determine whether the substances detected by the antiserums really are the hormones, or merely close relatives. Furthermore, this method cannot be used to determine the location in the body where the detected substances are actually produced. New techniques of molecular biology, however, provide a way to answer these questions. It is possible to make specific complementary DNA’s (cDNA’s) that can serve as molecular probes to seek out the messenger RNA’s (mRNA’s) of the peptide hormones.