Homeostasis And Response

Question 1

What is homeostasis?

Answer 1

The regulation of an organism / cells internal conditions in response to internal and external changes to maintain optimum conditions for function.

Question 2

What does homeostasis control?

Answer 2

Water levels, blood glucose concentration and temperature

Question 3

What do all control systems include

Answer 3

A receptor that detects stimuli, a co-ordination centre (brain and spine) which receives and processes information and an effector where responses are carried out and optimum levels are restored.

Question 4

What is the nervous system?

Answer 4

Allows humans to react to their surroundings and co-ordinate their behaviour

Question 5

How is the nervous system structured?

Answer 5

Receptors send information to cells (neurons) as electrical impulses and these electrical impulses are sent to the CNS and is co-ordinated so the effector can respond which could be muscles contracting or glands secreting hormones.

Question 6

What is the reflex arch and why is it important?

Answer 6

The reflex are is the passage of information from receptor → effector.it is rapid and automatic and doesn’t require conscious preventing injury.

Question 7

What are the functions of the structures in the reflex arch

Answer 7

Relay neuron - connects sensory and motor neuron
Synapse - gap between a neurons nerve signals diffuse across the gap and is sent to the next neuron as electrical signal
Motor neurone - impulses sent here then to effector
Sensory neurone - impulses are sent

Question 8

What is the practical for reaction time

Question 9

What is the endocrine system

Answer 9

A system of glands that secrete hormones into the bloodstream and the blood carries the hormones to the target organ creating an effect.it is slower than CNS but effects last longer

Question 10

What is the pituitary gland and its functions

Answer 10

The pituitary gland secretes all the hormones into the blood which then act on glands to produce different hormones and create an effect.

Question 11

Where is the : pituitary gland, pancreas thyroid, ovary, testes and adrenal gland located, and what do they secrete?

Answer 11

Location. Secretes
Pituitary gland brain many hormones
Ovary. Ovaries. Lh/ fsh/ oestrogen/pro
Testies. Testicals. Testosterone
Pancrease. Pancrease. Insulin
Thyroid. Neck. Thyroxine
Adrenal gland. Liver. Adrenaline

Question 12

What is blood glucose monitored and controlled by?

Answer 12

The pancreas

Question 13

What happens if blood glucose is too high

Answer 13

Insulin is produced and glucose moves from blood into cells and excess glucose is stored as glycogen

Question 14

What happens if blood glucose concentration is too low

Answer 14

Glucagon is secreted into the blood by the liver and converts glycogen into glucose

Question 15

What is type one diabetes?

Answer 15

When the body does not produce enough insulin which cause man blood glucose levels

Question 16

What is type 2 diabetes

Answer 16

When cells no longer respond to insulin causines high blood glucose concentration levels

Question 17

How can type 1 diabetes be treated

Answer 17

Insulin injections

Question 18

How can type 2 diabetes be treated.

Answer 18

Fixing diet and exercise

Question 19

What do reproductive hormones do during puberty?

Answer 19

Develop secondary sex characteristics

Question 20

What is oestrogen?

Answer 20

The main female hormone in the ovaries which releases an egg every 28 days this is called ovulation

Question 21

What is testosterone?

Answer 21

The main male hormone in the testes which is responsible for the stimulation of sperm production

Question 22

What do FSH, LH, oestrogen and progesterone do during the menstrual cycle?

Answer 22

FSH matures the egg
LH stimulates release of egg
Oestrogen/ progesterone maintain / build up uterus lining

Question 23

What are some examples of contraception and their uses?

Answer 23

Condoms/diaphragm barriers
FSH inhibiting pills prevent egg from maturing
Abstinence
Vasectomy/ clamping oviduct stops production of egg and sperm and is permanent
IUD prevents the implantation of an embryo and stops the release of hormones

Question 24

How can infertility be treated?

Answer 24

FSH and LH drugs
IVF

Question 25

What is IVF?

Answer 25

Other is given FSH and LH pills the produce and mature multiple eggs the eggs are then collected and fertilised by sperm in a lab incubator and then when embryos have formed into little balls of cells they are then implanted into the uterus to get pregnant

Question 26

Now have developed microscope techniques enabled IVF treatments to develop?

Answer 26

Micro tools can remove singular cells for genetic testing
They can monitor the growth of the baby to see chances for successful pergnancy

Question 27

What are the social and ethical issues of IVF?

Answer 27

Unused embryos are wasted potential human life
Genetic testing cal lead to selection of desired characteristics

Question 28

Why are some people against IVF?

Answer 28

It has a low success rate and can result in miscarriages and emotional stress leading to vomiting

Question 29

What does adrenaline do in the body?

Answer 29

It’s released when we are stressed or in fear and it increase heart rate and boosts delivery of oxygen and glucose to brain and muscles preparing outer body for fight or flight

Question 30

What does thyroxine do in the body?

Answer 30

It stimulates basal metabolic rates and is important for growth and development

Question 31

How are thyroxine levels controlled?

Answer 31

By negative feedback
When levels are high TSH is inhibited and thyroxine levels drop down back to normal