Bio + Chem + Physics Flashcards
1 key feature of nutrition
- taking in material for energy, development and growth
2 features of excretion
- removal of waste products of metabolism
+ toxic material
+ substances in excess - from organisms
1 key feature of reproduction
- the processes of reproducing more of the same kind of organisms.
2 features of growth
- permanent increase in size and dry mass
- by increase in cell number
+ increase in cell size
+ both
3 features of sensitivity
- detect or sense stimuli
- in the internal or external environment
- to make appropriate responses
3 features of respiration
- the chemical reaction in cells
- breaks down nutrient molecules
- release energy for metabolism
2 features of movement
- an action by an organism or a part of an organism
- causing a change of position or place
Factors of diffusion?
- Temperature
- Surface area
- Concentration gradient (Steepness)
- volume
- distance/thickness of the membrane
What state of matter does diffusion occur in?
- liquids and gases
Does diffusion use energy?
- Diffusion is a passive process
When does diffusion last?
- Until all molecules are evenly spread
What is diffusion?
- the net movement of molecules and ions
- from a region of higher concentration to lower concentration
- Down a concentration gradient
Animal cell vs. Plant cell, which will burst in pure water? Why?
animal will burst
Define plasmolysed cell
Cell shrinks until it’s shred, because it loses water (due to osmosis)
F
In a turgid cell, the outward pressure of the cytoplasm on a cell wall is called
Cell expands because it contains a lot of water (due to osmosis)
Turgid = Expands
What is a partially permeable membrane?
A membrane only allows some substances to go through it.
What is osmosis?
- Diffusion of water through a partially permeable membrane
- From a solution from high water concentration to low water concentration’s solution (higher water potential to lower water potential).
What thing don’t change by force
temperature (sometimes - air resistance)
density
mass
what force is needed to maintain a circular motion
The force directed toward the centre of the circle (centripetal force)
does constant speed require resultant force
NOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO
Tips
look carefully at the arrow
equilibrium =
No resultant force = no acceleration = constant speed = no resultant moment
Does change in direction = a resultant force that exists
YESSSSSSSSSSSSSSSSSSSSSSS
for an object to be stable, the object must have
- wide base
- centre of mass is directly over its base or pivot