Fichas
AQA, GCSE, combined science, BIOLOGY, paper 2
Fichas del conjunto (64)
- 1What is meant my the term 'homeostasis'?maintaining a stable internal environment in response to changes in external and internal conditions.
- 2What two types of communication is involved in 'homeostasis'?nervous and hormonal communication.
- 3What are the three automatic controls in 'negative feedback'?1. receptor
2. coordination centre
3. effector - 4What is the role of the 'receptor'?detects a stimulus
- 5What is the role of the 'coordination centre'?receives and processes the information then organises a response.
- 6What is the role of the 'effector'?produces a response, which counteracts the change and restores the optimum level
- 7What does 'CNS' stand for?the central nervous system.
- 8Where is the 'CNS' located in the body?the brain and the spinal chord.
- 9How is information passed through the 'CNS'?through neurons as electrical impulses.
- 10What are the 5 stages to the 'CNS'?stimulus, receptor, coordinator, effector, response.
- 11What is a synapse?the connection between two neurons is called a synapse.
- 12How is the nerve signal transferred?transferred by chemicals which diffuse through the gap.
- 13What is a 'reflex'?a rapid, automatic response to certain stimulus that don't involve the brain.
- 14What is the passage of information in a reflex called?the reflex arc.
- 15What are the 6 stages to the reflex arc?1. reflex arc goes through the spinal chord.
2. stimulus is detected by the receptor.
3. impulses travel along the sensory neurons.
4. impulses passed along a relay neuron.
5. impulses travel along a motor neuron.
6. when impulse reaches the muscle it contracts. - 16What are hormones?are chemical messengers sent int the in blood.
- 17What is the endocrine system?where hormones are produced and secreted into the blood.
- 18What are the 6 different glands in the body?pituitary glands, thyroid, adrenal gland, ovaries, testes, pancreas.
- 19What is the pituitary gland?produces all the hormones the the body - 'master gland'.
- 20What is the thyroid gland?produces 'thyroixine' for the rate of metabolism.
- 21What is the role of the 'adrenal gland'?produces adrenaline.
- 22What is the use of the ovary glands?produce 'oestrogen' - menstrual cycle.
- 23What is the role of the 'testes gland'?produces 'testosterone' - controls sperm production.
- 24What is the role of the pancreas in the endocrine system?produces 'insulin' - regulate glucose levels.
- 25What are the main differences between 'nerves' and 'hormones'?nerves: very fast action, act for a short time, act on a very precise area.
hormones: slower action, act for longer time, act in a general way. - 26What controls blood glucose concentration?pancreas.
- 27if blood glucose concentration is to high what does the pancreas secrete into the blood?insulin.
- 28Where is excess glucose stored?GLUCOGEN is stored in the liver and muscle cells.
- 29What is secreted into the blood is the blood glucose level is too high?insulin.
- 30What is secreted into the blood if glucose concentartion is too low?glucagon.
- 31What are the reproductive hormones in a female?ovaries - oestrogen.
- 32What is the male reproductive hormones?testes - testosterone.
- 33What are the primary characteristics?ones you are born with.
- 34What are secondary characteristics?ones you have after puberty.
- 35What is FSH?follicle stimulating hormone - causes maturation of an eff in the ovary.
- 36What is LH?Luteinising hormones - stu=imulates the release of the egg.
- 37What is oestrogen?causes the uterus lining to grow.
- 38What is progesterone?maintains the lining of the uterus.
- 39What is the barrier method of contraception?condoms and diaphragm - prevent the sperm reaching the egg.
- 40What is the surgical method of contraception.surgically sterilising man: sperm ducts are cuts ans ties.
female: oviducts are cute (permanent). - 41What is the chemical method of contraception?spermicides kill or disable sperms.
- 42What is the IUD method on contraception?intrauterine device - inserted into the uterus, to kill sperm ans stop implantation.
- 43What is the hormone based contraception?mixed pills, contraceptive implant, contraceptive patch.
- 44What is the role of the mixed pills in contraception?contains low doses of oestrogen and progesterone (stops FSH) - no eggs mature.
- 45What is the role of the contraceptive implant in contraception?progesterone under the skin released slowly.
- 46What is the role of the contraceptive patch in contraception?contains progesterone and oestrogen - shot into the arm .
- 47What is IVF?in vitro fertility.
involves giving FSH and LH to stimulate the maturation of several eggs.
(test tube baby) - 48What is a gamete?a sex cell.
- 49What fuses together in animals?sperm and egg cells.
- 50What fuses together on plants?pollen and egg cells in flowering plants.
- 51What type of reproduction allows for variation in offspring?sexual reproduction.
- 52What type of cell division takes place in the formation of gametes?meiosis.
- 53How many parent cells does asexual reproduction involve?1.
- 54What type of cell division takes place in asexual reproduction?mitosis.
- 55What is the main difference between mitosis and meiosis.mitosis - genetically identical offspring.
meiosis - allows variation in offspring. - 56What is DNA?genetic material of a cell.
- 57What are chromosomes?2 strands of DNA forming a double helix.
- 58What is a genome?the entire genetic material of an organism.
- 59What is a gene?segment of DNA (physical & characteristics of an organism).
- 60What is an allele?form of a gene - dominant (B), and recessive (b).
- 61What is meant by the term homozygous?pair of matching alleles (BB or bb).
- 62What is meant by the term Hetrozygous?pair of genes - dominant and recessive (Bb)
- 63What is meant by the term Genotype?set of genes in our DNA - genetic makeup of our characteristics.
- 64What is meant by the term Phenotype?the physical appearance (blue eyes, black hair).