Eukarya

Question 1

In the theory of endosymbiosis:
(a) State how (i) nucleus and endoplasmic
reticulum; (ii) mitochondria and (iii)
chloroplasts were originated from. (3)

Answer 1

1. NUCLUES & ER: infolding of cell membrane
2. mitochondria: purple bacteria
3. chloroplast: photosynthetic bacteria

Question 2

(b) Give three pieces of evidence to support

mitochondria and chloroplasts were evolved from prokaryotes. (3)

Answer 2

1. have own circular DNA
2. size
3. 2 membranes

Question 3

Ciliates:
(a) Which organism is the most prominent
example in this group? (1)
(b) How do they move? (1)
(c) How do they excrete? (1)

Answer 3

a) paramecium
b) beating action of cilia
c) by contractile vacuole

Question 4

a) Label a brown alga. (4)
(b) What is the special thing about their
blade? (1)
(c) What is their mode of nutrition? (1)

Answer 4

1. blade has a gassbladder for floating

2. mode of nutrition: photosynthetic

Question 5

Diatoms:
(a) Are they able to move? Why not? (1) (b) The shell is made up of silica. What is
theadvantageanddisadvantage ofthis material? (1+1)

Answer 5

1. non motile because they don’t have flagella

2. cilica advatange is protection, disadvantage: sink quickly ( lacks flagella, requires turbulence)

Question 6

Red algae: why are they red?

Answer 6

red pigment

Question 7

Green algae:
(a) In chlorophytes, what is special about
the shape of their chloroplasts? (1) (b) In charophytes, be able to label the
structure node, internode and the
reproductive structure. (1,1,1)
(c) What is cytoplasmic streaming? Which
cellular structure is responsible for it? (1,1)

Answer 7

a) shape= ribbon like and spirally arranged around vacoule (CHLOROPHYTES)
b) CS= movement go chloroplast, structure responsible= microtubules (cytoskeleton)

Question 8

Lichens: what do lichens consist of? (1+1); how do they benefit each other? (2)

Answer 8

1. photosynthetic bacteria/algae + fungus

PHOTOSYNTHETIC PARTNER: food and nutrients

FUNGI: protection , anchorage, mineral and H2O ABS

Question 9

Vagrant: What will happen if Vagrant is rehydrated and dry?

Answer 9

rehydrated= flat

dry = curl up