Maintaining Balance in Organisms Flashcards
What is pH a measure of?
The amount of acid or base in a substance
Which end of the pH scale is acidic? Which side is basic? What number is considered neutral?
Left is acidic. Right is basic. 7 is neutral
How much more acidic is something with a pH of 7 than something with a pH of 8?
10 times more acidic
What does a buffer do? Why do living things contain buffer?
It maintains the pH of a solution. Living things are buffered because they need their pH to stay in a narrow range
What happens to cause the pH of your blood to decrease? How does your body react to the decrease?
Blood pH decreases when it has more Co2 in it. The body reacts by increasing breathing rate to reduce Co2 content of blood
What is homeostasis?
Maintaining constant internal conditions regardless of how the external conditions change
Describe stress a an element of homeostasis
Stress is anything that threatens homeostasis… It is something that causes your body to have to react in some way
Why would your body need to remove excess water to maintain homeostasis? Where does this happen? (which organ)
So that your blood is not diluted. Need certain concentrations of glucose, proteins, etc. Your kidneys remove the excess H2O from your blood
Why does your body need to remove wastes to maintain homeostasis?
Sometimes to make space for substances you need Co2 to O2. Sometimes because the waste can be toxic
Why does your body need to exchange oxygen and carbon dioxide to maintain homeostasis?
O2 needed for cellular respiration (energy requirements) and Co2 molecules make blood acidic and take up space
What are red blood cells responsible for? White blood cells?
Red: carry oxygen
White: soldier cells, fight diseases
Describe a feedback system. Give an example.
Involves sensors receiving information triggering a response.
ex: Co2 level in blood turns blood acidic then triggers a higher breathing rate
What is the difference between a physiological and a behavioral response? Give some examples of each
Physiological: your body responds - ex: Goosebumps
Behavioral: your response that you choose - ex: putting on a sweater
What types of physiological responses are involved in maintaining body temperature?
Shivering, Goosebumps, restricted blood flow to the skin, arms & legs
Which body system is responsible for monitoring body temperature?
The Nervous System
Where are the sensors for body temperature monitoring located?
On the skin - nerves
If you have an oxygen deficiency how does your body react?
Increased breathing rate
What happens to your rate of respiration when you sleep?
It slows down, you don’t need as much O2
What is the job of the human liver?
Detox blood and produce bile for digestion
In order for the endocrine system to work correctly is has to work very closely with what other system?
Nervous system
Where do the endocrine system and the nervous system meet?
Between the hypothalamuses and pituitary gland
What is the basic job of the endocrine system?
Send chemical messages to target cells to affect change in the body
What are hormones?
Chemical messengers
How are hormones delivered to different parts of the body?
By the circulatory system. They travel in the blood
Pituitary Gland
Location:
Function:
Location: attached to the rain below the hypothalamus
Function:*regulated by hypothalamus (nervous system)
*connects nervous system to the endocrine system
*secretes 9 hormones that regulate many functions, and other endocrine glands
Thyroid
Location:
Function:
Location: lower part of larynx
Function: *regulates metabolism
*maintains hear beat, body temperature, and blood pressure
*produces thyroxin (regulates metabolism)
Adrenal glands
Location:
Function:
Location: two of them; located on top of each kidney
Function: *adrenaline - fight of flight, stress increases, hormone released, glycogen released into the blood stream (positive feedback example
*heart rate & blood pressure increase and more blood is sent to the heart, brain, and muscles
*not part of excretory system
Gonads: Ovaries, Testes
Location:
Function:
Location: side of uterus or scrotum
Function: *estrogen/ progesterone - regulate secondary sex characteristics and pregnancy
*testosterone - regulate secondary sex characteristics
Pancreas
Location:
Function:
Location: beneath the stomach
Function: *regulates blood sugar
*produces insulin to reduce blood sugar by bonding glucose together into glycogen which lowers blood pressure
*glucagon raises blood sugar by releasing glucose
Thymus
Location:
Function:
Location: near sternum/heart
Function:*development of immune system - stimulates the development of T- cells for immune defense
Pineal Gland
Location:
Function:
Location: base of brain
Function: *secretes melatonin to regulate sleep patterns
Parathyroid (4 of them)
Location:
Function:
Location: back of thyroid (behind)
Function: *parathyroid hormone - increases calcium ions for normal bone growth, muscle tone, and neural activity
