When the SA Node Is Not Working Correctly, the Heart

question 17

Multiple Choice

When the SA node is not working correctly, the heart has a backup pacemaker called the ____________________ .

• A) coronary sulcus
• B) chorda tendinea
• C) atrioventricular (AV) node
• D) His-Purkinje system

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Definitions:

Progesterone

A steroid hormone secreted by the corpus luteum of the ovary and by the placenta, which acts to prepare the uterus for implantation of the fertilized egg.

Secreted by Ovary

Refers to substances, such as hormones (e.g., estrogen and progesterone), that are released or produced by the ovaries.

After Ovulation

The phase after ovulation, known as the luteal phase, involves the secretion of progesterone to prepare the uterus for potential pregnancy.

LH

Luteinizing hormone, a hormone produced by the anterior pituitary gland that triggers ovulation in females and stimulates testosterone production in males.