The button-like structure that holds homologous chromosomes together at their middles during cell division is called the

CENTROMERE

Explanation:

The CENTROMERE is the primary constriction region where the identical DNA molecules are most tightly bonded to each other during mitosis and meiosis.

The typical chromosome in metaphase is composed of two sister chromatids joined by the centromere.

Surrounding the centromere, we can find the kinetochores. These are laminar proteinic structures forming a plate where the spindle and kinetochore fibers will join during chromatids separation.

The position of the centromere defines the chromosomes as acrocentric, metacentric, or submetacentric.

type 2 happens when excess consumption of high-sugar foods flood the blood supply with glucose and reduce the production and effectiveness of insulin. if a person has prediabetes, they can reduce the risk of full diabetes through regular exercise and a balanced, low-sugar diet.

both anaerobic and aerobic respiration use glucose (or other carbohydrates), proteins and lipids to produce atp and nadh. cell uses those energy molecules, obtained from food and   breaks them down during the chemical reactions of respiration. in anaerobic respiration, nadh is regenerated to nad+ by enzymes lactate dehydrogenase (lactate is produced, e.g. in muscle cells) or by alcohol dehydrogenase where ethanol is produced (alcohol fermentation), while in aerobic respiration, electrons from nadh are deposited in the mitochondria to regenerate nad+ (electron transport chain. anaerobic respiration produces 2 atp per molecule of glucose compared to aerobic respiration where about 38 atp molecules are produced.