Combined Biology - B5 Homeostasis and Response Flashcards
Name the cells that detect stimuli (changes in the environment)
Receptors
What is homeostasis?
The regulation of internal conditions of a cell or organism to maintain optimum conditions for function in response to internal and external changes
or
“Maintaining internal body conditions”
Why is homeostasis important?
To maintain optimum conditions for enzymes and all cell functions.
List three things that are controlled by homeostasis.
1) Blood glucose
2) Body Temperature
3) Water levels
What is the gap between two neurones called?
Synapse
What type of signal travels along neurones?
Electrical
What type of signal is transmitted across a synapse?
Chemical
Q.
a) What does CNS stand for?
b) What two organs make up the CNS?
a) Central nervous system
b) Brain and spinal cord
Name the organ from the CNS that is not involved in a reflex response.
Brain
List, in order, the neurones involved in a reflex response.
sensory neurone → relay neurone → motor neurone
What are the two types of effector?
Muscles and Glands
Put the following stages in order for a nerve response.
Effector / stimulus / response/ coordinator / receptor
- Stimulus
- Receptor
- Coordinator
- Effector
- Response
What is reaction time?
The time it takes for an organism to respond to a particular stimulus
Q. What is the name for the group of glands that produce hormones?
Q. How do the hormones secreted by these glands get to their target organ?
- Endocrine glands
- They travel in the blood
Compare nerve and hormones responses
- Hormones are slower and act in a more general way.
- Nerve responses are faster and act in a more precise way.
- Hormone responses act for longer than nerve responses.
- Hormones are chemical signals. Nerve responses are electrical signals.
a) What is the name of the ‘master gland’?
b) Where is the ’master gland’ located?
c) What is the job of the ’master gland’?
a) Pituitary gland
b) Brain
c) Stimulate other glands to secrete hormones
Can you locate the following glands on the human body?
adrenal / thyroid / ovaries / testes / pancreas / pituitary
Which part of the body coordinates blood glucose concentration?
Pancreas
Name the hormone that reduces blood sugar levels.
Insulin
Describe how blood glucose is controlled if it gets too high.
- The pancreas produces insulin.
- Insulin causes glucose to move from the blood into the cells.
- In liver and muscle cells, excess glucose is converted to glycogen for storage.
What is the role of FSH in the menstrual cycle?
Causes an egg to mature
What is the role of LH in the menstrual cycle?
Stimulates the release of an egg
What is the role of Progesterone in the menstrual cycle?
Maintains uterus lining
Q.
a) How does barrier method contraception work?
b) Name one type of barrier method contraception.
a) Prevents sperm reaching the egg
b) Examples include: condom, diaphragm e.t.c.
