Biology4 8D Microbes - unicellular organisms Flashcards Preview

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Flashcards in Biology4 8D Microbes - unicellular organisms Deck (46)
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1

Which of the 5 different kingdoms contains cells without a nucleus?

The only cells without a nucleus are bacteria. Their DNA is loose DNA in the cytoplasm.

2

What is the name for the cells with a nucleus?

The name for the cells with a nucleus is Eukaryote.

3

Why does the pH of milk drop as it changes into yoghurt?

The pH drops as lactic acid is made by the microbes added to the milk. This makes the milk curdle and thicken as well as making the yoghurt taste sour.

4

In a food chain the numbers decrease from one level to another. Can you explain why?

In a food chain the numbers decrease from one level to another there is less energy available for the next level of the food chain. The less energy available, the fewer organisms it can support.

5

What are the stages in the growth of a population of a microbes?

The stages in the growth of a population of a microbe are slow increase in number, fast increase in number, maximum population, death.

6

What is the role of the nucleus in a cell?

The nucleus is the organelle which contains DNA and so controls the cell.

7

What is the name for the cells without a nucleus?

The name for the cells without a nucleus is Prokaryote.

8

What is the role of the cell wall in a cell?

The cell wall is the part of a cell which supports and protects the cell.

9

Which 2 kingdoms contains multicellular organisms?

The 2 kingdoms which contains multicellular organisms are the plant and animal kingdom.

10

Name a food made by a bacteria

An example of a food made by a bacteria is yoghurt.

11

Why are decomposers important for an ecosystem.

They break down waste and recycle carbon.

12

Why do multicellular organisms (plants and animals) need transport systems?

Multicellular organisms (plants and animals) need transport systems because it would take too long to deliver oxygen to tissues in the middle of your body by diffusion. 

13

What kind of respiration makes lactic acid?

Lactic acid is made by anaerobic respiration ( when no oxygen is available)

14

What is the disadvantage of being unicellular?

The disadvantage of being unicellular is that the cell cannot get too large as it depends on diffusion for the movement of food and oxygen into the cell.

15

What does a bacterial cell use its flagellum for?

A bacterial cell use its flagellum (plural flagella) to move itself around.

16

When you make bread you put it in warm place to prove and increase in size. Why does the bread rise?

The microbes (yeast - a fungus) releases carbon dioxide

17

What is the role of the chloroplast in a cell?

The chloroplast is the part of a cell which makes food/glucose by photosynthesis. It contains the green pigment chlorophyll which absorbs light energy..

18

What is the role of the ribosomes in a cell?

The ribosomes are the pace in a cell where proteins are made.

19

Name a kingdom that contains unicellular organisms that never contain mitochondria or a nucleus

A kingdom that contains organisms made of cells that never have mitochondria or a nucleus is the bacteria kingdom.

20

What is the role of the mitochondrion in a cell?

The mitochondrion is the organelle where aerobic respiration takes place.

21

What 3 resources do microbes need to survive?

To survive microbes need warmth, moisture, and food (such as glucose)

22

Name a kingdom that contains organisms made of cells that never have cell walls.

A kingdom that contains organisms made of cells that never have cell walls is the animal kingdom. The other 4 kingdoms all have cell walls.

23

What is the role of the cell surface membrane in a cell?

The cell surface membrane wall is the part of a cell which controls what enters and leaves the cell

24

What do we mean by a producer in an ecosystem?

A producer in an ecosystem is one which can photosynthesise.

25

Name a kingdom that contains unicellular organisms that can have chloroplasts.

A kingdom that contains unicellular organisms that can have chloroplasts is the protoctists. it cannot be plants as these are multicellular!

26

Which microbes produce alcohol?

The microbes which produce alcohol are fungi such as yeast. They do this when they respire anaerobivally. (without oxygen). it is called fermentation.

27

Yeast cells reproduce asexually. How do they do this?

Yeast cells increase by budding. Eventually the bud breaks off the parent microbe and becomes an individual. It will be an exact genetic copy

28

Glucose is an organic compound. Give the name of one other organic compound

Any kind of food group such as protein, starch, fat, lipid, oil, carbohydrate

29

Why do the numbers of microbes in a petri dish of agar reach a peak and then drop?

The numbers of microbes in a petri dish of agar reach a peak and then drop because they run out of food and die.

30

What is asexual reproduction?

Asexual reproduction does not need a second parent or sperm or egg cells (gametes) . It makes an exact copy of the parent (called a clone)