L3 Protozoans:

Question 1

What are the main features of protozoans?

Answer 1

Single celled
eukaryotic
motile
heterotrophic
complex

Question 2

What is a pellicle?

Answer 2

combination of the cell membrane and th cytoskeleton, a protective membrane

Question 3

What is a test?

Answer 3

Hard covering that is secreted by the animal, or made up of substances retrieved from the environment

Question 4

What are the different locomotion methods in protozoans?

Answer 4

By cilia
By pseudopodia
by flagella

Question 5

How do protozoan use cilia to move?

Answer 5

beat in a metachronal wave

Question 6

How do protozoan use pseudopodia to move?

Answer 6

Means false foot, is a temporary extension of the body, formed from cytoplasmic fluid filled extensions. Foot forms from a change in viscosity of the cytoplasm, becomes more fluid, streaming occurs in the direction which the false foot is going

Question 7

How do protozoan use flagella to move?

Answer 7

Tail like projection to propel the protozoa

Question 8

What are the different methods of food acquisition?

Answer 8

pinocytosis
receptor mediated endocytosis
phagocytosis

Question 9

What is pinocytosis?

Answer 9

The ingestion of a liquid into a cell by the budding of small vesicles from the cell membrane. The vesicles capture small particles, which then reform on the plasma membrane

Question 10

What is receptor mediated endocytosis?

Answer 10

Receptors on the membrane pick up specific molecules in the environment, which are then engulfed

Question 11

What is phagocytosis?

Answer 11

When large items are engulfed. Receptors are less specific, but is essentially the same as endocytosis.

Question 12

What digests the contents of the vesicles once ingested?

Answer 12

Lysosomes, break these products down

Question 13

What are the different methods of reproduction employed by the protozoans?

Answer 13

• Primitive, by fission

- May be sexual, haploid adults undergo meiosis to form diploid zygote - mitosis to become haploid adult

Question 14

When does alternation of the generations occur?

Answer 14

When the diploid life stage is extended

Question 15

What is the endosymbiont theory?

Answer 15

eukaryotic cells may have evolved when multiple cells joined together into one, lived in a symbiotic relationship with a mitochondrion etc.

Question 16

What different groups are present in the protozoans?

Answer 16

Ameboid, flagellates, spore forming, ciliates

Question 17

What are the different types of pseudopodia?

Answer 17

Filopodia

lobopodia

Question 18

How do amoeba reproduce?

Answer 18

Asexually, by binary fission

Question 19

What are entamoeba histolytica?

Answer 19

Two forms of this amoeboid:
non parasitic live in the gut, feeds on bacteria and can be beneficial.
Parasitic form can cause amoebic dysentery. Invade intestine walls to feed in blood and tissues. Can cause an abscess which rupture. Once in the blood stream, can be fatal

Question 20

How do the amoeboid move?

Answer 20

Mainly pseudopodia

Question 21

How do the spore-forming - (apicomplexans) - reproduce?

Answer 21

increase rapidly by asexual fission. can also produce sexual macro and micro gametes,

Question 22

How do the spore-forming species spread from host to host?

Answer 22

practically all parasites, spread by oocysts

Question 23

What are oocysts?

Answer 23

a cyst containing a zygote formed by a parasitic protozoan

Question 24

What are plasmodium?

Answer 24

species causing malaria, transmitted through female mosquito. infective sporozoite passes from its salivary glands into the wound

Question 25

Describe the plasmodium lifecycle

Answer 25

Individuals injected into a new host from the mosquito. Multiply in the parenchyma cells, then migrate to red blood cells. Gametocytes are then produced. May be drawn up by a biting mosquito, and transform into gametes in the stomach. Then encyst on the stomach wall as oocysts. Multiply by asexual reproduction and then migrate to the salivary glands, to invade a new host

Question 26

What are gametocytes?

Answer 26

A cell that divides by meiosis to form gametocytes

Question 27

What methods have been put in place to control for malaria parasite?

Answer 27

Vaccine
Chemical DDT to control mosquito population
Mosquito nets
GM mosquitos to sterilise males
Gene editing

Question 28

What is Toxoplasma gondii?

Answer 28

Spore forming, has a rodent host, appears to influence the behaviour of the rat, so it appears less afraid of cats, which are the definitive host of the parasite

Question 29

What are the flagellates?

Answer 29

Characterised by the presence of one or more flagella at some or all stages

Question 30

By what method do flagellates reproduce?

Answer 30

Usually asexual, by longitudinal fission, sex occurs in a few groups

Question 31

What are Trichonympha?

Answer 31

Free living, found in cockroaches and helps to breakdown cellulose to glucose, which. the cockroaches can use

Question 32

What are Trypanosoma brucei?

Answer 32

A parasite, which causes sleeping sickness, transmitted by the tsetse fly. There are two sub species. One take 2-3 years to take affect in humans, and if untreated can enter the blood brain barrier.
Other species affect game, but if transmitted to human host will cause death within 6-8 weeks

Question 33

What are variant surface glycoproteins and why are they an adaptation?

Answer 33

Proteins on the surface that are constantly changing, meaning the host cannot become immune

Question 34

What methods have been put in place to control the tsetse fly?

Answer 34

set traps with cow urine

Not raising cattle

Question 35

What are the ciliates?

Answer 35

Class which use cilia for locomotion

Question 36

What method of reproduction do the ciliates use?

Answer 36

Asexual, with macronuclei, and sexual with micronuclei

Question 37

What is conjugation?

Answer 37

Process by which one bacterium transfers genetic material to another through direct contact