Organism Level Systems | OCR GCSE Combined Science Biology, Foundation tier (J250)
Organism Level Systems
- 76 questions
- 8 subtopics
- Paper 1 (Biology)
- Paper 1 (Biology)
Organism Level Systems is examined in Paper 1 (Biology).
It covers the nervous system and coordinated responses, the reflex arc, hormones and the endocrine glands, hormones in reproduction and the menstrual cycle, methods of contraception, homeostasis and control systems in the body, insulin and the control of blood glucose and type 1 and type 2 diabetes.
Sample questions from Organism Level Systems
Answer each one closed book first, then open the answer.
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The nervous system and coordinated responses
What is an effector?
Show the answer
A muscle or a gland that carries out the response when an impulse arrives from a motor neurone. -
The reflex arc
Explain why a reflex arc produces a faster response than a voluntary action.
Show the answer
The impulse passes through only three neurones and two synapses and does not travel to the conscious part of the brain for a decision to be made. -
Hormones and the endocrine glands
What is an endocrine gland?
Show the answer
A gland that releases its hormones directly into the blood rather than through a duct. -
Hormones in reproduction and the menstrual cycle
Which is the main female reproductive hormone and where is it made?
Show the answer
Oestrogen, made in the ovaries. -
Methods of contraception
Give one advantage and one disadvantage of using the contraceptive pill.
Show the answer
It is more than 99% effective when taken correctly, but it can cause side effects such as headaches and raised blood pressure and gives no protection against sexually transmitted infections. -
Homeostasis and control systems in the body
Why must body temperature be held close to 37 °C?
Show the answer
Enzymes work fastest near this temperature and are denatured above it, so metabolic reactions would otherwise run at the wrong rate or stop altogether. -
Insulin and the control of blood glucose
What effect does insulin have on the body cells?
Show the answer
It makes them take glucose out of the blood and into the cell. -
Type 1 and type 2 diabetes
How is type 1 diabetes treated?
Show the answer
With injections of insulin, matched to the person's meals and exercise.
The 8 subtopics
One subtopic is one session. Work down the list.
| Subtopic | What it covers | Questions |
|---|---|---|
| The nervous system and coordinated responses | The central nervous system, what sensory, motor and relay neurones, receptors and effectors do, how sensory and motor neurones differ in shape, synapses and neurotransmitters, what a coordinated response is and why many receptors and connections help, the stages from stimulus to response, catching a falling glass, and why nervous responses are faster than hormonal ones. | 16 |
| The reflex arc | What a reflex action is and why it protects the body, the parts of a reflex arc in order, why a reflex is faster than a voluntary action, the relay neurone in the spinal cord, how synapses slow an impulse, the hot pan and blinking reflexes, why a person is aware of a reflex, and why the same stimulus always gives the same response. | 10 |
| Hormones and the endocrine glands | What a hormone and an endocrine gland are, how hormones travel in the blood yet affect only some organs, the main endocrine glands including the adrenal glands, the hormones of the ovaries and testes, and how hormonal and nervous responses compare. | 8 |
| Hormones in reproduction and the menstrual cycle | Testosterone and oestrogen and what each does at puberty, what FSH does and where it is released from, the role of progesterone, the length of the menstrual cycle and when an egg is released, and what happens to the uterus lining without fertilisation. | 8 |
| Methods of contraception | How the combined pill, other hormonal methods, condoms and other barrier methods prevent pregnancy, the advantages and disadvantages of each, sterilisation, why natural methods are less reliable, and which methods are the most effective. | 8 |
| Homeostasis and control systems in the body | What homeostasis is, the conditions held constant inside the body, why body temperature stays close to 37 °C, the three parts of a control system, how the body corrects a change in temperature, and why the water content of the blood is controlled. | 8 |
| Insulin and the control of blood glucose | Which organ monitors blood glucose, how insulin makes body cells take up glucose, storing it as glycogen in the liver and muscles, why blood glucose falls after a meal and must be controlled, and insulin control as negative feedback. | 8 |
| Type 1 and type 2 diabetes | What type 1 and type 2 diabetes are, when each usually appears, insulin injections and why insulin cannot be swallowed, diet and exercise for type 2, risk factors, symptoms, and glucose in the urine. | 10 |
How the guide is worked
Answering a question from memory stores it far better than reading the answer again. The guide runs that as a fixed procedure on one subtopic at a time, about twenty minutes a session.
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Step 1 · Closed book
Cover the answers. Work through one subtopic and write down what you can. Leave blanks where you have nothing.
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Step 2 · Open book
Go back to the top. Read each printed answer and write it out in full, including the ones you had right.
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Step 3 · Closed book again
Same questions, same order, from memory. The gap between pass one and pass three is the session result.
Read the full method, the return schedule and the research behind it.
Nearby topics
OCR GCSE Combined Science Biology, Foundation tier Active Recall Guide
Every topic, not just this one. 806 questions with their answers.