Animal coordination, control and homeostasis 🐾 Flashcards
Where are hormones produced
In the endocrine gland
Describe the endocrine glands communicate with organs around the body
The endocrine glands release chemicals called hormones into the blood which carries them around the body to the target organs
What hormone does the adrenal gland release
Adrenaline
What hormone does the thyroid gland produce
Thyroxine
Which hormones does the pituitary gland produce
ACTH
FSH
LH
growth hormone
What do we mean by metabolism
All the chemical reactions that occur in the body
State the three conditions are required to measure resting metabolic rate
Warm room
gap in time since eating
no movement
How does thyroxine (produced in the thyroid gland) affect the metabolic rate as an example of negative feedback
Causes heart cells to contract more strongly and rapidly
Increases the rate at which proteins and carbohydrates are broken down inside cells
Recall the steps in how thyroxine controls the metabolic rate
low levels of thyroxine stimulates production of TRH in hypothalamus
this causes release of TSH from the pituitary gland
TSH acts on the thyroid to produce thyroxine
when thyroxine levels are normal thyroxine inhibits the release of TRH and the production of TSH
Define the term negative feedback
A control mechanism that reacts to a change in conditions, such as temperature, by trying to bring the condition back to a normal level
Explain how adrenaline (produced in the adrenal glands) prepares the body for ‘fight or flight’
increases heart rate
increases blood pressure
increases blood flow to the muscles
raises blood sugar levels (muscles have energy to contract)
How does the body cause an increased heart rate and blood pressure (ADRENALINE)
Heart muscle cells contract
more rapidly (heart rate)
and more strongly (blood pressure)
How does the body create an increased blood flow to muscles (ADRENALINE)
Diameter of blood vessels LEADING TO MUSCLES widens
and Diameter of blood vessels LEADING TO OTHER ORGANS narrows eg. Digestive system
How does the body increase blood sugar concentration (ADRENALINE)
Stimulates liver cells to change glycogen to glucose and release it into the blood
Explain how an increase in adrenaline prepares the body for a sudden burst of activity
Insures the muscles have a good supply of oxygen and glucose for aerobic respiration which enables contraction of muscles for fight/flight response
What is ovulation
When an egg is released from an ovary
What is fertilisation
When a sperm cell fuses with an egg
What is menstruation
When the unfertilised egg and part of the uterus lining a shed from the body
What time period in menstruation is fertilisation most likely to occur
days 14-25
What is the function of the menstrual cycle
To allow a woman to be fertile
When does ovulation occur
Day 14
What are the 4 key hormones involved in regulating the menstrual cycle
Oestrogen
Progesterone
LH
FSH
Which gland releases FSH and LH
Pituitary gland
What’s are oestrogen and progesterone released by
Ovaries
What is the function of the FSH hormone
Causes the maturation of an egg follicle before ovulation
What is the function of the LH hormone
Stimulates the release of the egg
What is the function of the oestrogen hormone
Repairing/thickening the uterus lining 
What is the function of the progesterone hormone
Maintains the uterus lining