Body Balance Flashcards
What is homeostasis? (h)
Homeostasis is your body’s ability to regulate and maintain conditions inside your body, regardless of changes to external environment.
What are some conditions in the body that need to be kept consistent? (H)
- Body temperature at 37’c
- The amount of water inside our body
- Blood sugar levels
How does the body maintain homeostasis? (H)
Negative feedback loops
It occurs to reduce/remove the original stimulus to maintain homeostasis.
Explain the role of the stimulus response model? (H)
- First we need receptors to detect changes (stimulus).
- We need a processing center (CNS) to receive information and coordinate our response.
- Finally we need effectors to produce the response.
Stimulus meaning (H)
Any detectable change in the environment
Receptor meaning (H)
A cell or group of cells that receive stimuli: sense organ.
Control centre meaning (H)
A place where a series of operations is directed.
Effector meaning (H)
A bodily part that becomes active in response to stimulation (such as muscles or glands)
Response meaning (H)
Response of the effector feeds back to reduce the effect of stimulus and returns variable to homeostatic level
What is a negative feedback loop?
Negative feedback is a response triggered by changed conditions and serves to reverse the change.
Explain how blood glucose levels are regulated (H)
Insulin (Low Blood Glucose): When blood glucose is high (after eating), the pancreas releases insulin. Insulin helps cells absorb glucose for energy and stores excess glucose in the liver as glycogen.
Glucagon (High Blood Glucose): When blood glucose is low (between meals or during fasting), the pancreas releases glucagon. Glucagon signals the liver to break down glycogen into glucose and release it into the bloodstream.
Homeostasis: This balance between insulin and glucagon keeps blood glucose levels stable, typically between 70-100 mg/dL.
What happens in diabetes. (H)
Type 1: The immune system mistakenly attacks and destroys insulin-producing beta cells in the pancreas. Pancreas produces little/no insulin, which is essential for helping cells absorb glucose from the blood. Without enough insulin, glucose builds up in the bloodstream (hyperglycemia) because cells can’t take it in for energy.
Type 2: The body becomes resistant to insulin, or the pancreas doesn’t produce enough insulin to maintain normal blood glucose levels. Insulin is less effective at helping glucose enter cells, so blood glucose levels rise.
What is a positive feedback loop (H)
A positive feedback loop is when response to a stimulus amplifies the original signal, rather than counteracting it. The output of the system enhances/accelerates the activity of the system, leading to a greater response.
What is the role of the endocrine system?
To maintain homeostasis (a stable internal environment) and to coordinate the body’s long-term activities by sending chemical signals throughout the body.
What is a hormone? How does it travel in the body?
A chemical messenger that is secreted from glands into the bloodstream and affects cells in another part of the body. They only work on cells called target cells.
Name 3 areas that the endocrine system regulates
- Growth and development
- Levels of salts and sugars in your blood
- Appetite
What is an endocrine glad? What does is secrete?
An endocrine gland is a gland that secretes hormones into the bloodstream.
How do hormones ‘know’ which cells are their target cells
Target cells have receptors to ‘recognise’ the hormones and allow them to influence that cell to respond.
What controls the release of hormones? Give examples of different stimuli
External stimuli - via nerves from sensory organs in the nervous system eg. loud noise
Internal stimuli - via nerves and other hormones from inside your body eg. your sick and develop a fever
Why is the pituitary gland called the master gland?
It controls the functions of many of the other endocrine glands
Name an example of an endocrine disorder. What has gone wrong to produce these systems.
Diabetes, occurs when the pancreas does not produce enough insulin.
DNA
The blueprint of life and is in all living things, it stores the genetic material for an organism.
Deoxyribonucleic acid
Gene
Segment of DNA that codes for a protein and trait
Chromosomes
contains gene’s that determine the traits for the organism
Nucleus
A part of the cell containing DNA and RNA and responsible for growth and reproduction
Nucleotide
a compound consisting of a nucleoside linked to a phosphate group. Nucleotides form the basic structural unit of nucleic acids such as DNA.