biology igcse Flashcards
what are the characteristics of living organisms
MRS GREN
movement
respiration
sensitivity
growth
reproduction
excretion
nutrition
what is the chemical equation of cellular respiration
glucose+oxygen —> carbon dioxide + water
define movement
the change of place or position caused by an organism
define respiration
the chemical reaction in cells that break down to release energy for metabolism
define sensitivity
the ability to detect and respond to changed of the environment
define growth
the permanent increase in size and dry mass of a living organism
define reproduction
the process of making the same kind of organism
define excretion
the removal of waste products for metabolic processes
define nutrition
taking in materials for energy, growth and development
define species
the group of similar living organisms that can breed with one another to produce a fertile
what are the two levels of classification in the binomial system
genus + species
A student defined respiration as being the same as breathing. Are they correct? Provide a reason to support your answer.
Breathing and respiration are two completely different things but interrelated body processes that assist body organs to function properly
Humans breathe but bacteria do not. Is it correct to state that bacteria are alive? What makes you think that?
Bacteria is not considered a living organism as it does not share all the characteristics of living organisms
What is the energy released in cellular respiration used for?
You need energy to grow, move around, to excrete cell division
Why is it important to say that energy is released, not produced.
As energy cannot be created nor destroyed, only transferred
Why does an increase in the number of cells cause growth?
the increase in the number of cells increase the volume and size of an organism
Why does the amount of dry mass in an organism cause growth?
Dry mass is made up of organic molecules when there is more organic molecules, the dry mass increases
what are the two types of reproduction
sexual and asexual
How do the two forms of reproduction differ from each other?
Sexual is where offsprings are a result of 2 different gametes fusing together.
Asexual is where offspring are from the same parent
What is metabolism?
Metabolism is the term used for chemical reactions that go on inside an organism’s body.
How is metabolism linked to excretion?
Metabolic processes toxic products and it is removed from the body through excretion.
This image shows a cow producing faeces. Is this an example of excretion? What makes you think that?
No, as faeces is not excretion, it is undigested food, Excretion as the removal of the waste products of metabolism and substances in excess of requirements.
What is the purpose of nutrition?
To give the substances as it needs to release energy
What is the difference between a nutrient and nutrition?
Nutrient is a substance you consume and nutrition is the process of taking in and using those substances.
