Unit 1: Chapter 3 Flashcards Preview

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Flashcards in Unit 1: Chapter 3 Deck (58):
1

Exergonic reactions

Release energy, more chemical energy in the reactants than the products

2

Endergonic reactions

Consume energy, more chemical energy in the products than the reactants

3

Requirements for life for a unicellular and multicellular organism

- access to a source of energy
- obtain organic molecules
- access water
- exchange gases
- remove waste products

4

To obtain energy organisms must be able to...

- capture energy from an external source
- convert this energy into chemical energy of organic molecules
- transfer energy produced in excess into organic molecules for storage

5

Types of energy

Thermal
Electrical
Radiant
Chemical

6

How do plants and algae capture energy?

By trapping radiant energy (sunlight)

7

How do animals and fungi capture energy?

Capture in the form of chemical energy from the organic molecules in their food

8

Is sunlight energy useful for cells? Why?

No, because sunlight is a diffuse form of energy that can be transported by cells or stored in that form in cells

9

How do plants change sunlight energy into chemical energy?

Photosynthesis

10

Word and chemical equation of photosynthesis

Carbon dioxide + Water > Glucose + Oxygen
6CO2 + 12H2O > C6H12O6 + 6O2

11

How does an animal break down their food?

Digestive enzymes produced by the animal break down the large organic molecules

12

In what form is energy stored?

ATP, glucose, glycogen (animals), starch (plants), fats and proteins

13

ATP

- Can be used immediately by cells
- Single step reaction
- Releases energy in small amounts
- Powers all energy-requiring reactions that keep all organisms alive

14

ATP reaction

ATP + Water > ADP + phosphate
When ATP combines with water it loses a phosphate through hydrolysis which releases energy and then the energy from glucose regenerates ATP to allow a phosphate to bond with ADP to make ATP

15

Glucose

C6H12O6
The chemical energy can be released and transferred to ATP
In cells, chemical energy of glucose is released by cellular respiration
1 molecule of glucose can produce 34-36 ATP

16

Glycogen

Polysaccharide in animals
Stored in liver and muscle
When needed glucose can be released from these energy stores
Excess glucose from food is stored as glycogen

17

Starch

Polysaccharide in plants
When needed glucose can be released to make energy

18

Fats

Tryglicerides stored in adipose tissue
Slower release energy stores
Largest in the human body
Energy in fats comes from fatty acids

19

Inorganic molecules

Water
Oxygen
Nitrogen
Carbon dioxide
Mineral quartz
Iron ore hematite
Aluminium ore bauxite

20

Organic molecules

Carbohydrates
Proteins
Lipids
Nucleic acids

21

Heterotrophs

Organisms that must obtain preformed organic molecules through feeding ie; animals

22

Autotrophs

Organisms that can make their own organic molecules from inorganic raw materials ie; plants

23

Different types of sunlight energy

High energy short wavelength ultraviolet radiation
to
lower energy infra red radiation

24

Chlorophyll

Allow plant cells to catch sunlight
Gives leaves their green colour
Embedded in the grana
Absorb sunlight best in blue to red peaks

25

Why are chloroplasts green?

Because the chloroplast does not absorb the light, it reflects it

26

Accessory pigments

Light capturing pigments
Carotenoids
Phycocyanin
Phycoerythrin

27

What light capturing pigments do plant cells contain?

Chlorophyll and carotenoids

28

Leaf structure components

Waxy cuticle
Upper/lower epidermis
Stroma
guard cell
Vascular bundle - phloem and xylem

29

Photosynthesis

Builds simple inorganic molecules (carbon dioxide and water) into complex organic molecules (glucose) that provide energy for living

30

Where are chlorophylls located?

On the grana membrane of chloroplasts

31

How many chloroplasts does a photosynthetic cell have?

40-200

32

Oxygenic photosynthesis

When oxygen is one of the products of photosynthesis

33

Leaves

- flat shape provides a large area to catch sunlight
- contains photosynthetic cells with chloroplast to catch light
- stomata on the underside of the leaf allow carbon dioxide to enter
- covered with a waxy cuticle
- internal air of the leaf allows diffusion of carbon dioxide
- vascular tissue contains xylem vessels and phloem tissue

34

Xylem vessels

In vascular tissue and transport water to photosynthetic cells

35

Phloem tissue

In vascular tissue to transport the products of photosynthesis from these cells to all other cells throughout a plant

36

Stems

- thick-walled xylem vessels give rigidity to stem
- branching of stems allows leaves to be positioned to catch more sunlight
- xylem vessels transport water and minerals from roots
- phloem tissue moves products to non-photosynthetic cells

37

Roots

- an extensive root system taps a significant volume of soil for water and mineral salts
- at the tip of the root, there are root hairs which have a large surface area for the absorption of water and minerals

38

How do organisms survive when they have no access to sunlight?

They become chemosynthetic meaning that they can build organic molecules from the oxidation of inorganic molecules from carbon dioxide

39

Aerobic respiration

Cellular respiration requiring oxygen
- Exergonic (energy releasing)
- C6H12O6 + 6O2 > 6CO2 +6H2O
- most energy released is lost as heat (60%)
- 40% efficiency

40

Anaerobic respiration

- anoxic (oxygen-free) environments
- called fermentation
- ATP is produced more rapidly

41

Step 1 of aerobic respiration

- in cytosol of cell
- glycolosis - glucose breaks down into 2 molecules called pyruvate
- energy released produces 2 ATP
- pyruvate is transported into matrix of mitochondria

42

Step 2 of aerobic respiration

Krebs cycle

43

Step 3 of aerobic respiration

- the inner membrane of mitochondria
- electron transport chain
- where oxygen comes so that 32 ATP can be produced

44

Rates of aerobic respiration

- different muscle tissues have different energy requirements
- measured by consumption of oxygen or uptake of glucose

45

Lactic acid fermentation

in skeletal muscles, after glucose is broken down into pyruvate an enzyme converts it to lactic acid

46

Phosphocreatine

Is in the skeletal muscles and can transfer its phosphate to produce ATP
ADP + PCr > ATP + Cr

47

Difference between aerobic and anaerobic respiration

oxygen not required for anaerobic
anaerobic had fast ATP production, aerobic is slower
anaerobic can be sustained for short time, aerobic for a long time
anaerobic is less efficient, aerobic is more
2 ATP made for anaerobic, 34 made for aerobic
end products; anaerobic can have lactate and water, aerobic has carbon dioxide and water

48

Factors that affect photosynthesis

Light
Carbon dioxide
Temperature
Water

49

Components of chloroplast

Outer membrane
Inner membrane
Thylakoid
Grana
Stroma

50

2 stages of photosynthesis

Light dependant
Light independant ( calvin cycle)

51

Light dependent stage

water reacts with sunlight then NADP carries hydrogen to calvin cycle which produces Oxygen gas and NADPH+
located in grana or thylakoid membrane

52

Light independant stage

NADPH+ reacts with carbon dioxide to produce glucose and NAPD which goes back to the light-dependent stage
located in the stroma

53

Thylakoid

the individual membranes

54

Grana

a stack of thylakoids

55

Stroma

jelly like substance surrounding the grana

56

Plastid

energy converter organelle

57

Anaerobic respiration in animals

Glucose > Lactic acid + energy
C6H12O6 > 2C3H6O3 + ATP

58

Anaerobic respiration for plants ( fermentation)

Glucose > Ethanol + Carbon dioxide + Energy
C6H12O6 > 2C2H5OH + 2CO2 + ATP