Homeostasis 2nd year topic 4

Question 1

Define Homeostasis

Answer 1

Homeostasis is the ability of the body to maintain a stable internal environment despite a changing external environment

Question 2

Mention some factors which need to be kept constant in the body.

Answer 2

Temperature
Blod glucose level
Ph
Oxygen
Carbon dioxide
Water
Mineral ions
etc

Question 3

Why do these components need to be in balanced conditions at all times?

Answer 3

Because these components they are crucial in order to give out all of the necessary conditions needed for the cells to carry out their processes. tO ENSURE SURVIVAL. To ensure that conditions in the body are kept optimum for surival,enzymes need a specific emperature to work in

Question 4

What do we mean when actions regaridng homeostasis can be voluntary or involuntary?

Answer 4

Voluntary:drink when you are thristy,you open the dorr when you are hot,put on clothing when cold

Involunatry:shivering or sweating

Question 5

Which 2 organs systems in the body are crucial for controling the other organ systems? Give a reason for your answer.

Answer 5

The endocrine and the nervous system work together to ensure that coordination takes place. Therfere these organ systems ensure that they create an environment in which all cells can survive and function

Question 6

What exactly is the internal environment in the body?

Answer 6

The tissue fluid is the extracellular fluid which bathes all cells in the body

Question 7

What is the importance of the tissue fluid?

Answer 7

The tissue fluid which bathes all cells in the body and fills the spaces between cells. Its mportant because it proides a means of delivering materials to the cells,intercellular communication and removing metabolic waste.

Question 8

What is the internal environment and external environment in the body?

Answer 8

Internal: extracellular fluid which is made up of the tissue fluid and plasma
External: the air surrounding the body

Question 9

Explain in breif how the body maintains homeostasis

Answer 9

The body will detect the changes ,relay this information to the integration (brain),and elicit a command to specific cells to alter theri function to restore the property back to its original value.

Question 10

What does tissue fluid consist of?

Answer 10

Coenzymes
hormones
neurotransmitters
oxygen
fatty acids
water
cellular products

Question 11

Mention the homeostatic regulators in the body

Answer 11

Stimulus
receptor
integration
effector
response

Question 12

What is a stimulus?

Answer 12

A chnage in the internal or external environment

Question 13

What is receptor?

Answer 13

The body part that detects the chnage

It recevies nformation that something in the nevironment is chnaging

Question 14

What is the integrator?

Answer 14

The brain

Because the brain will receive the information from the receptro ,it processes it

Question 15

What is an effector?

Answer 15

It receives information from the control centre it either opposes it or enhances the stimulus. ex: muscles and glands

The effector is responsible to make a change,depending on the information the sensor was sendingWhat

Question 16

What is the set point?

Answer 16

The set point is the optimum conditions that the body is in after it has carried out homeostatsic regulation. ex: 37 degrees celscius or blood sugar of 4-7

Question 17

What type of mechnaism does the body make use of to maintain homeostasis?

Answer 17

Feeback mechanism

Question 18

What is coordination?

Answer 18

Coordination is the process by which organs and systems in the body work together to respond to changes detected both internally and externally. It involves receptors detecting stimuli and sending messages to effectors to produce specific responses.

Question 19

Where are receptors found in the body?

Answer 19

Sense organs: eyes nose ears mouth
or they can be found on cells. Cells can have dffrent receptors on their membranes

Question 20

Define negative feedback

Answer 20

When there is a change from the optimum value, the body reacts total opposite of what is happening to reverse this change.
The end product produced will reduce the stimulus of that same process. ex: blood glucose, body temp,or the production of progesterone which inhibits the production of FSH and LH so that no more follicles and oocytes mature.

Question 21

Define positive feedback

Answer 21

When the production of a substance will cause a further activation of the reaction.

Ex: FSH secreted by the pituitary gland will stimulate the production of oestrogen. oestrogen will stimulate the pituitary gland to keep on producing FSH which aids in follicle development in the ovary during the menstrual cycle

Labour: the uterine contractions will cause the production of oxytocin by the pituitary gland. This hormone will keep on being produced which further aids in the uterine contractions to help the baby be deliveered out from the uterus

Question 22

Which gland is responsible for regulating blood glucose level in the body?

Answer 22

Pancreas

Question 23

Name a situation when the blood glucose level can rise and another situation when the blood glucose level can drop?

Answer 23

Rise: after a meal. For example a meal which contains high ammounts of carbohydrates,will be broken down and will increase the blood glucose levels. Even for example when the liver will secrete glucose

Drop:after excercise. This is due to the high rate of respiration due to high energy excercise or missing a meal will cause the blood sugar to decrease

Question 24

What will the pancreas secrete if the blood glucose level will rise too much?

Answer 24

Hormone:insulin

Question 25

What will the pancreas secrete if the blood glucose level will drop?

Answer 25

Hormone: Glucagon

Question 26

What are the cells called which make up the pancreas?

Answer 26

Islets of Langerhans

Question 27

Where are the pancreas located in the body?

Answer 27

They are a gland whch are located behind the stomach and are attached to the duodenum via the pancreatic duct

Question 28

How can the pancreas acts both as an exocrine and an endocrine gland?

Answer 28

Endocrine: because it releases hormones directly into the blood stream (insulin which is responsible for regulating blood glucose levels)

Exocrine: because it also has a digestive function because it secretes pancreatic juice

Question 29

How does the pancreas know wether the blood glucose level drop or has risen?

Answer 29

Because the pancreas are made up of chemoreceptors which detect the change

Question 30

What are the 2 types of cells which make up the islets of Langerhans?

Answer 30

Alpha cells which secrete glucagon

Beta cells which secrete insulin

Question 31

Give a function of chemoreceptors

Answer 31

They measure the sugar concentration in the blood as the blood flows through the pancreas.

Question 32

What will happen if the blood sugar level is too low?

Answer 32

The hormone glucagon is secreted by the pancreas,which will stimulate the liver to chnage glycogen into glucose and amino acids also to glucose

Question 33

Mention another situation when glycogen and amino acids are also converted into glucose

Answer 33

During stress, the hormone adrenaline which is secreted by the adrenal glands which are located near the kidneys can also stimulate the liver to convert glycogen and amino acids into glucose in order to raise the blood sugar

Question 34

What will happen if the blood sugar level increases?

Answer 34

The chemoreceptors will detect the chnage,this will stimulate the pancreas to secrete insulin. Insulin will stimulate the liver and muscle cells to absorb the excess glucose and use it. It causes the conversion of glucose into fat and glycogen which can be sused for storage.

Question 35

What is another role of insulin?

Answer 35

It increases the rate of respiration to break down excess glucose and release ATP energy molecules

Question 36

Where are the chemoreceptors located in the pancreas?

Answer 36

Islets of langerhans