What is another word for a communicable disease?
infectious
What is a stimulus?
a change we can detect and respond to
what type of medicine kills bacteria?
antibiotics
what is a smaller part of a population or area that scientists study called?
sample
What is diffusion?
the natural movement of particles from an area of high concentration to an area of low concentration
What is a microorganism/agent that causes disease called?
pathogen
what is an impulse?
an electrical signal that travels along nerve cells
how do antivirals work?
they stop viruses from replicating
what term describes how common a species is in a habitat?
abundance
What does volume tell us?
the amount of space something takes up
What type of white blood cell ingests pathogens?
phagocyte
What is a hormone?
a chemical messenger released by a gland
what is a transgenic organism?
an organism that contains DNA from another species
A 2 m2 quadrat contains 10 sunflowers
The total area of the habitat is 100 m2
> How many sunflowers in the area?
500 sunflowers
what is the name for an exchange surface that only allows certain substances to pass through
semi-permeable membrane (or partially permeable membrane)
What is an autoimmune disease?
a type of disease that occurs when the body's immune system attacks its own cells
What is homeostasis?
the maintenance of a constant internal environment
why are viruses considered "non-living"?
they cannot carry out life processes (cannot produce energy on their own)
Which sampling method can be used to collect insects from long grass?
Sweep nets: organisms in long grass
What happens to the SA:V ratio as an organism's size increases?
decreases
How do memory cells help protect the body?
they recognise a pathogen and produce the correct antibodies much faster
why does a hormone not affect every cell it reaches?
only target cells/organs can respond to it
What do enzymes do?
Name one example where they are used in the human body:
they speed up a reaction without being used up or changed themselves
Digestion: breaks down starch into glucose
Respiration: Enzymes help the process of aerobic respiration
How can scientists ensure estimates are more accurate? Name at least two ways:
taking more samples, increasing the sample area, placing sample areas randomly
Why does a larger surface area help an organism exchange substances more efficiently?
there is more space for particles to diffuse across