Test 1, bio

Question 1

Homeostasis defintion

Answer 1

maintaining a constant internal environment (temperature level, pH, oxygen levels)

Question 2

Respiration defintion

Answer 2

Breakdown of carbohydrates to release energy

Question 3

photosythesis definition

Answer 3

Build up of carbohydrates and release energy

Question 4

Levels of organisation

Answer 4

atoms, molecules, organelles, cells, tissues, organ, organ system, organism

Question 5

1.magnification formula
2. how many cm in a micrometer?
3. how do you find magnification?

Answer 5

1. Magnification = image size/actual size.
2. 1 micrometer = 10,000 cm
3. a) measure the image in cm with a ruler (eg. 9cm)
   b). convert cm into μm (9–> 90,000)
   c). substitute into formula (eg. m=I/A : m =9cm/0.9 μm)
   d). 90000/0.9 = 10
   M=100,000

Question 6

dependant vs independent

Answer 6

independant = what you choose
dependant = what is affected

Question 7

why are cells small

Answer 7

because smaller things have a larger surface area : volume ratio, therefore making diffusion easier, because the exchange of materials happens faster

Question 8

differences between diffusion, active transport, and active transport

Answer 8

DIFFUSION: passive transport-down concentration gradient
OSMOSIS: passive trasport
ACTIVE TRASPORT: active transport (energy needed) - against concentration gradient

Question 9

Diffusion

Answer 9

movement of molecules from an area of high–>low concentration.
*no energy needed
*in gases and liquids
*non semi-permeable membrane
*faster if heat/energy

Question 10

Osmosis

Answer 10

The movement of water molecules only from dilute –>concentrated solution
*semi-permeable membrane
*faster if heat/energy

Question 11

Active transport

Answer 11

Movement of molecule from LOW–>HIGH concentration
*requires energy (from ATP)
*against concentration gradient
*require semi-permeable membrane

Question 12

Turgid cell

Answer 12

too much water.
Happens when placed into solution with less concentrated liquid (placed into HYPOtonic), causing water to move into cell due to osmosis

Question 13

Flaccid cell

Answer 13

Happens when placed into solution with less concentrated liquid (placed into HYPERtonic), causing water to move into cell due to osmosis

Question 14

Ribosomes

Answer 14

make proteins for the cell

Question 15

Factors that affect rate of diffusion/osmosis

Answer 15

Temperature - The particles have more kinetic energy, so the move faster, increasing diffusion rate

Distance - the shorter the distance the cells have to travel, the faster the rate of diffusion

Higher concentration gradient - the bigger the difference of concentration in the two substances, the faster diffusion happens

Surface area : volume - the smaller something is (eg. Cells) the higher the ratio of surface area:volume.)