T18

Question 1

early vascular plants - rhynia

Answer 1

no leaves, no specialised roots, just above ground stems and below ground stems

these can be separated into terminal and lateral sporangia

Question 2

terminal sporgania

Answer 2

spore bodies on end of stems, leaves with this trait evolved

Question 3

lateral sporangia

Answer 3

sporagnia on side of stem , leaves evolved from these

Question 4

leaves structure

Answer 4

high surface area which is negative will absorb lots of light so lose lots of heart
also need lots of stomas to prevent overheating and evaporation of water

need to find a good balance as too many stomata would increase co2 conc which is toxic

made it an issue for plants to have leaves for a while because of this

Question 5

terminal sporgania evolved into… plants

Answer 5

seed plants called monilophyta - ferns

Question 6

lateral sporgania evolved into ….

Answer 6

lycophyta
microphyll leaves which caused serve limits in growth form
- can specialise parts of stem to be smaller to produce spore bearing cones which protects

Question 7

microphyll leaves

Answer 7

evolved from out growths on a stem

Question 8

megaphyll leaves

Answer 8

evolved from branched ste - fern leaves

Question 9

ferns

Answer 9

are monilophyta plants
sporangia borne on underside of fern leaves

Question 10

movement in animals

Answer 10

animals have muscles

sessile animals- to attach to or root to substrate

motile animals are the moving animals

Question 11

motile animals can either be ….

Answer 11

passive - drift in current or float in air, require little energy

active - utilises energy to move and find food
search for mate
escape predator and migrate

Question 12

in order to move, need to overcome

Answer 12

gravity, drag, inertia and friction
this is all dependent on body size and thickness of medium

Question 13

amoebiod movement

Answer 13

not seen in whole animal organisms
-pseudopod extendes forward to move as the internal fluid flows into them - seen in white blood cells

Question 14

flagellar movement

Answer 14

seen in sperm cells to swim

Question 15

ciliary movement

Answer 15

uses cilliar to move with powerstroke
seen in swimming larvae and ctenophores

powerstroke to move forward, recovery stroke to retract

Question 16

musclar movement

Answer 16

all animals expect sponges
3 types of muscles
-smooth - in blood vessles or digestive tract
cardiac - in heart with low fatigue rate
skeletal - paralell fibres called myofibrils divided into sections called sacromeres which have a myosin and actin protein

Question 17

muscles can only contract

Answer 17

because of this, must require skeleton to attach to
muscles work in antagonistic pairs to move

Question 18

how does muscles contract?

Answer 18

1. active site on actin exposed as ca2+ bind to troponin
2. myosin head forms a cross bridge with actin
3. during powerstrok the myosin head bends and ADP and phosphate is released
4. new molecule of ATP attaches to myosin head causing cross bridge to detach a

this process repeats

Question 19

hydrostatic skeleton

Answer 19

longitudinal muscle and circular muscle work together
when the L relaxes and C contract
- squeezes body segement down and narrows, causing lengthening

when L contracts and C relaxes
- bigger and wider body but shorter

Question 20

Rigid exoskeleton

Answer 20

mollusc shells - calcium carbonate to protect and use for locomotion

cuticle exoskeleton- chitin which is strong and flexible, these shed as animal growsr

Question 21

rigid endoskelton

Answer 21

hard element in soft tissue
- internal spciules - protect but no locomotion
internal ossicles - protection
internal bone - protection support and locomotion