What this topic covers
B3: Organism level systems has 3 subtopics:
- B3.1 Coordination and control - the nervous system
- B3.2 Coordination and control - the endocrine system
- B3.3 Maintaining internal environments
← Back to topics
GCSE OCR Foundation Combined Science Biology · Topic 3 of 6
B3: Organism level systems – GCSE OCR Foundation Combined Science Biology revision notes
Choose a subtopic. Nervous control, endocrine control and homeostasis. 14 lessons in 3 subtopics.
Revise B3: Organism level systems for GCSE OCR Foundation Combined Science Biology, including B3.1 Coordination and control - the nervous system.
14
Lessons
3
Subtopics
B3: Organism level systems lessons by subtopic
14 lessons, grouped by subtopic.
B3.1 Coordination and control - the nervous system
B3.2 Coordination and control - the endocrine system
- Introduction to the Endocrine System
- Major Endocrine Glands and Their Locations
- Male and Female Reproductive Hormones
- The Menstrual Cycle
- Hormonal methods of contraception
- Non-hormonal methods of contraception
- Evaluating contraceptive methods
B3.3 Maintaining internal environments
More in this course
Go back to the full GCSE OCR Foundation Combined Science Biology topic list, or practise this topic with past-paper questions.
Frequently asked questions
What is B3: Organism level systems?
Nervous control, endocrine control and homeostasis. 14 lessons in 3 subtopics.
What are the four stages of the menstrual cycle?
The menstrual cycle has menstruation (days 1-5), when the lining is shed and FSH rises; the follicular phase (days 6-13), when an egg matures and oestrogen thickens the lining; ovulation (day 14), triggered by the LH surge; and the luteal phase (days 15-28), when progesterone maintains the lining. The The Menstrual Cycle notes cover this in full.
What is ovulation?
Ovulation is the release of a mature egg from the ovary, occurring approximately every 28 days in the menstrual cycle. The Male and Female Reproductive Hormones notes cover this in full.
What is a vasectomy?
A vasectomy is male sterilisation: surgical cutting or blocking of the vas deferens tubes so sperm cannot mix with semen during ejaculation. The Non-hormonal methods of contraception notes cover this in full.
What are the side effects of the combined pill?
Side effects of the combined pill can include nausea and mood changes, and there is a small increased risk of blood clots. The Evaluating contraceptive methods notes cover this in full.
What is homeostasis?
Homeostasis is the regulation of internal conditions of a cell or organism to maintain optimum conditions for function in response to internal and external changes. The What is Homeostasis and Why is it Important? notes cover this in full.
Where is the pancreas located?
The pancreas is an elongated gland located behind the stomach. The Major Endocrine Glands and Their Locations notes cover this in full.
What hormones control the menstrual cycle?
Four hormones control the menstrual cycle: FSH, released by the pituitary gland, causes an egg to mature; LH stimulates the release of the mature egg (ovulation); oestrogen, from the developing follicle, rebuilds and maintains the uterine lining; and progesterone, from the corpus luteum, maintains the thick uterine lining. The The Menstrual Cycle notes cover this in full.
What is insulin?
Insulin is a hormone produced by the pancreas that causes glucose to move from the blood into cells when blood glucose concentration is too high. The How the Pancreas Controls Blood Glucose notes cover this in full.