Body Balance - Bio Flashcards
What is homeostasis
The body’s ability to regulate and maintain a stable condition inside your body, regardless of changes to the external environment.
What are some of the conditions that need to be maintained
Temperature
The amount of water inside your body
Blood sugar levels
How does the body maintain homeostasis
Feedback
The body uses feedback loops to monitor internal bodily functions such as temperature, blood pressure, pH levels, and blood glucose levels.
Endocrine system
Hormones produced by the endocrine system help regulate and maintain homeostasis by controlling various body functions, including metabolism, growth, and reproduction.
What is negative feedback
Negative feedback is a response triggered by changed conditions and serves to reserve change. It occurs to remove/reduce the original stimulus to maintain homeostasis
Example of negative feedback
Bodies temperature is too low
Body temperature low → Skeletal muscles shiver to generate heat, hairs stand up → Body temperature rises → Hypothalamus turns warning off
What happens in diabetes?
Diabetes disrupts the normal negative feedback loop involved in blood glucose regulation.
The role of endocrine system
Made up of endocrine glands
Glands secrete chemical messages called hormones
The endocrine system regulates male and female development, how our body uses energy, appetite, and response to stress
Name at least three areas that the endocrine system regulates.
Pituitary gland, Thyroid gland, Adrenal gland
What is a hormone
Hormones are chemical messengers produced by glands in the body that travel through the bloodstream to regulate various physiological processes and maintain homeostasis.
How do hormones recognise which cells are their target cells?
Target cells have a special receptor that recognises the hormone and allows them to influence that cell
What is the role of the hypothalamus? Where do you find it?
The hypothalamus is found in the brain, its role is to signal to the pituitary gland if conditions need to be corrected
Why is the pituitary known as the master gland?
Signals other glands to produce their hormones when needed, this is also found in the brain
What does the Pituitary gland produce
growth hormone
(found in the brain)
What does the Thyroid gland produce
Thyroxine - Regulates body energy usage
(found in the front of the throat)
What does the Adrenal gland produce
Adrenaline - How we respond to stress, fight or flight mode
(found on top of your kidneys)
What does the Pancreas produce
Insulin and Glucagon
(found just behind your stomach)
What does the Ovary produce
Oestrogen and Progesterone - Female development and controls menstruation and pregnancy
What do the Testes produce
Testosterone - Male development
What does the Pineal gland produce
Melatonin - Controls sleeping and walking patterns
(found in your brain)
What are chromosomes? Where are they found in a cell?
A chromosome is a structure found in the nucelus of a cell that carry genetic information in the form of genes
What are genes? What are they made of? What do they code for?
Genes are made of DNA, which consists of nucleotides arranged in a double-helix structure.
Genes code for specific traits or characteristics, such as eye colour or blood type.
What is the difference between a gene and a genome?
A gene is a specific segment of DNA, while a genome refers to all the genetic material in an organism.
What is the function of DNA? Describe its structure. What holds the two strands together
DNA’s function is to store and transmit genetic information; it is a double helix structure held together by hydrogen bonds between nucleotides.
What is a nucleotide? Name the three components of a nucleotide.
A nucleotide is the building block of DNA, consisting of a sugar molecule, a phosphate group, and a nitrogenous base
What is the main function of RNA? Describe its structure.
The main function of RNA is to carry genetic information from DNA to ribosomes for protein synthesis
What are the similarities and differences between RNA and DNA?
DNA
- Double strande
- Deoxyribose sugar
- A,T,C,G
RNA
- Single stranded
- Ribose sugar
- A,U,C,G
What are proteins? What function do they have in a cell?
Proteins are molecules made of amino acids that perform various functions in cells.
What are the steps required to produce a protein from DNA?
The steps required to produce a protein from DNA include transcription and translation,
What is transcription
RNA is synthesised from a DNA template,.
What is translation
RNA is used to assemble amino acids into a protein at the ribosome.
What phases are part of interphase?
Growth 1, Synthesis, Growth 2
What is G1
This is where the cell starts to grow and create more proteins
What is Synthesis
The genetic material is replicated, chromosomes are doubled but are still attached by a chromatid
What is G2
Increases in size, there is a checkpoint at the end of this to make sure there are enough proteins before mitosis
What is occurring in mitosis?
In mitosis, the cell’s nucleus divides into two identical daughter nuclei, each with the same number and type of chromosomes as the original cell.
What are the differences between cytokinesis in animal and plant cells?
In animal cells, cytokinesis involves the formation of a cleavage furrow, which pinches the cell membrane inward until the cell is divided into two daughter cells.
In plant cells, cytokinesis involves the formation of a cell plate, which forms along the equator of the cell and gradually develops into a new cell wall, eventually separating the cell into two daughter cells.
How do mutations result in a lack of control of the cell cycle?
Mutations in genes that regulate the cell cycle can disrupt the normal checkpoints and control mechanisms, leading to uncontrolled cell division allowing cells to divide uncontrollably and potentially leading to the development of cancer.
What is a checkpoint
which the cell examines internal and external cues and “decides” whether or not to continue
Role of DNA helicase
To unwind and separate the DNA double helix into two single strands during processes such as DNA replication
Role of DNA polymerase
Adds nucleotides complementary to the template strand, ensuring the accurate copying of genetic information
Explain the term semi-conservative. Draw a diagram to show this.
Each newly synthesised DNA molecule contains one original parent strand and one newly synthesised daughter strand.
What is the name of the original strands of DNA? What is the name of the new strands?
New strands strands - Daughter cells
Old strands - Parent cells
What is produced at the end of the process of DNA replication?
two identical copies of the original DNA molecule
Why do cells need to divide/reproduce
- If a person grows more cells are required
- If the original cells become damaged
Prophase
The chromosomes condense and wind up
Metaphase
The nucleus dissolves and the cell’s chromosomes condense and move together, aligning in the centre of the dividing cell.
Anaphase
Each chromosome’s sister chromatids separate and move to opposite poles of the cell.
Telophase
The cell is nearly done dividing, and it starts to re-establish its normal structures
What is cytokinesis
In cytokinesis, the original cell officially splits after all chromosomes are disconnected going from 1 parent cell to two daughter cells
