21 public questions tagged with this topic.
Maternal cardiac output increases during pregnancy due to increased blood volume and heart rate to meet the metabolic demands of both mother and fetus.
Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Human Reproduction and Reproductive Health, Topic: Gametogenesis, menstrual cycle and reproductive strategies.
In fetal circulation, the placenta serves as the main organ for oxygenation and gas exchange since the lungs are non-functional. This follows from latest NCERT 2026-27 principle explaining the concept clearly for NEET students in simple steps as per rationalized syllabus.
Ref: NCERT Biology Textbook - Latest Edition for Academic Session 2026-27 (Zoology section, Rationalized Textbook for Class XI and XII), Chapter: Biology - Zoology portion (Latest NCERT Textbooks for Academic Session 2026-27 - Rationalized Edition for Class XI and XII), Topic: Structural organization, ph
In early pregnancy, the corpus luteum is the primary source of progesterone until the placenta takes over later in gestation. This follows from NCERT principle where relation explains outcome clearly for students.
Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Biology - Zoology portion covering relevant system and function, Topic: Structural organization and physiology.
Progesterone maintains uterine quiescence (prevents contractions) throughout pregnancy until labor begins.
Ref: NCERT Class 12 Biology Chapter 2: Human Reproduction Menstrual Cycle Fertilization Implantation Pregnancy Parturition Lactation
Human placental lactogen (hPL) is secreted by the placenta and helps prepare the breasts for lactation by altering maternal metabolism.
Ref: NCERT Class 12 Biology Chapter 2: Human Reproduction Menstrual Cycle Fertilization Implantation Pregnancy Parturition Lactation
In fetal circulation, the placenta serves as the main organ for oxygenation and gas exchange since the lungs are non-functional.
Ref: NCERT Class 12 Biology Chapter 2: Human Reproduction Menstrual Cycle Fertilization Implantation Pregnancy Parturition Lactation
The blood-placental barrier, primarily formed by trophoblast layers, prevents direct mixing of maternal and fetal blood while permitting the exchange of nutrients, gases, and wastes.
Ref: NCERT Class 12 Biology Chapter 2: Human Reproduction Male Reproductive System
Maternal cardiac output increases during pregnancy due to increased blood volume and heart rate to meet the metabolic demands of both mother and fetus.
Ref: NCERT Class 12 Biology Chapter 2: Human Reproduction Male Reproductive System
Progesterone prevents uterine contractions and helps maintain pregnancy.
Ref: NCERT Class 11 Biology Chapter 19: Chemical Coordination and Integration Gonads - Testis and Ovary Hormones
Progesterone helps maintain pregnancy by preventing uterine contractions and supporting the uterine lining.
Ref: NCERT Class 11 Biology Chapter 19: Chemical Coordination and Integration Gonads - Testis and Ovary Hormones
Erythroblastosis fetalis occurs when an Rh-negative mother carries an Rh-positive fetus.
Ref: NCERT Class 11 Biology Chapter 15: Body Fluids and Circulation Lymph and Circulatory Pathways
