If you listen carefully to someone's heart beat through a stethoscope you can hear a double beat. A faint one followed by a louder one . Suggest a reason for this

Which statement best describes a keystone species? o a. it has littlelmenetic variation. it has an extremely high population. 0 b. 0 c. it remains unaffected by all environmental changes. od. it has a strong influence on the ecosystem. 0 e. it's the first species to populate a new ecosystem.

Milk production during breastfeeding is increased by the suckling of a newborn from his mother's nipple. this type of feedback mechanism best describes a positive or negative

2.) insulin is needed to your cells take in sugar from your blood. after you eat a candy bar, will your insulin gene be expressed or repressed? 3.) all cells have the same dna, and they all make the same proteins. true or false? the answers are 2.) expressed3.) false