Algae

Question 1

Name the 4 colour classifications of algae

Answer 1

Red, Brown, Green and Golden

Question 2

Green algae posess ________

Answer 2

Chloroplasts

Question 3

Chloroplasts in green algae contain ______ which play a role in ______

Answer 3

Pyrenoids which play a role in concentrating Co2 inside the cell as CO2 in water has a lower concentration than CO2 in the air.

Question 4

What are the 3 types of reproduction observed in algae

Answer 4

Vegetative reproduction, asexual reproduction and sexual reproduction

Question 5

Describe asexual reproduction in algae

Answer 5

The cell divides via mitosis to produce genetically identical daughter cells.

Question 6

Describe sexual reproduction in algae

Answer 6

Haploid cells with no cell wall are released from the parent cell. These haploid cells then swim around until they find a partner of the opposing mating type, they then fuse to form a diploid zygote. The zygote forms a thick cell wall around it and withdraws it’s flagella creating a zygospore. The zygospore then sinks to the bottom of the body of water where it can survive harsh conditions until germination takes place. Where upon it performs meiosis before releasing haploid cells again.

Question 7

Describe vegetative reproduction in algae

Answer 7

A new cell is formed from a fragment of a pre-existing cell

Question 8

List the growth requirements for algae

Answer 8

Sunlight, H2O, CO2 and nutrients (nitrogen and phosphate).

Question 9

What is eutriphication

Answer 9

Nutrient enrichment of aquatic enviroments

Question 10

Describe the stages of natural eutriphication

Answer 10

1. An abundance of nutrients in the enviroment (N&P)
2. Stimulates heavy growth of algae and aquatic plants
3. Which means increased photosynthesis
4. Which leads to increased regeneration of nutrients amd orgamic compouns
5. Which stimulates further growth
6. Phytoplankton become concentrated in the upper layer giving it a murky green appearance
7. Light penetration decreases as turbidity (cloudiness) increases
8. Biological productivity becomes restricted to a small layer of surface water
9. Algae, remains of plants and sediments drift to the bottom
10. Bacteria partly convert dead organic material into inorganic substances
11. Bacteria activity depletes the oxygen levels of the deep water and bottom . Eventually the lake/pond is no longer able to support aerobic life.

Question 11

Describe a beneficial algae

Answer 11

Chlorella vulgaris is a green algae found in aquatic enviroments. Chlorella vulgaris is used as a food source and dietary supplement by humans due to its high protein content along with the vitamins and minerals it provides. Chlorella vulgaris is also a candidate for an alternative biofuel source.

Question 12

Describe a harmful algae

Answer 12

Prototheca algae can grow on the human body. They lack chloroplasts and are the causative agent of protothecosis which can cause skin legions on immuno-compromised individuals.

Question 13

Describe an algae found in water

Answer 13

Chlorella vulgaris is a green algae found in aquatic enviroments. Chlorella vulgaris is used as a food source and dietary supplement by humans due to its high protein content along with the vitamins and minerals it provides. Chlorella vulgaris is also a candidate for an alternative biofuel source.

Question 14

Describe an algae that can habitate in the human body

Answer 14

Prototheca moriformis algae can grow on the human body. They lack chloroplasts and are the causative agent of protothecosis which can cause skin legions on immuno-compromised individuals.

Question 15

Describe an algae found in soil

Answer 15

Species of chlorella can be found in moist soil (they prefer acidic soil) which has access to sunlight. Theses algaes are a source of oxygenisation and serve as asource of carbon once they die