practice
what are the levels of biological organasition
Cell → Tissue → Organ → System → Organism
the order of what decides and amino acid sequence
dna
What does the excretory system do
Excretory: Removes wastes like urea and CO₂; maintains water and salt balance through kidneys, lungs, skin.
What are proteins
Proteins are folded chains of amino acids that perform many roles
What are examples of receptors
hormones, neurotransmitters
what is negative feedback
A response that returns the body to normal conditions.
what is transcription
where in the nucleaus dna changes to mrna
What does the nervous system do
Nervous: Sends electrical signals to detect and respond to stimuli through the brain, spinal cord, nerves.
what do enzymes do
speed up chemical reactions
What do structural proteins do
provide support
what is an example of negative feedback with bloodsugar
Example: High blood sugar → pancreas releases insulin → blood sugar decreases
when in the ribosome mRNA → amino acid chain → protein folding
What does the respiratory system do
Respiratory: Exchanges gases—brings in O₂ and releases CO₂ through the lungs, trachea.
what do antibodies do
recognize and help destroy pathogens.
What are examples of structural proteins
collagen, keratin
what is the smalest unit of life
cells
what is gene exspertion
All cells have the same DNA, but only specific genes are expressed in each cell type
What does the immune system do
Immune: Protects against pathogens using white blood cells, antibodies, lymph nodes.
What is an example of enzymes
digestion
What do transport proteins do
Transport proteins move substances across membranes.
how does the body mantain homeostasis
Organs work together to maintain homeostasis
What does the circulatory system do
Circulatory system: Transports oxygen, nutrients, and waste via blood through the heart, blood vessels.
What does the reproductive system do
Reproductive: Produces gametes; allows fertilization and development of offspring.
what do receptors do
receive signals
What determines how a molecule interacts