Biology

Question 1

Eight Life Processes

Answer 1

Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, Nutrition, Cells

Question 2

Humans: Vertebrates

Answer 2

Animals that have a backbone

Question 3

Humans: Mammals

Answer 3

Vertebrates that have hair/fur and milk glands

Question 4

Humans: Primates

Answer 4

Mammals with collar bones and grasping fingers

Question 5

Cells

Answer 5

The building blocks of life, that are responsible for all of life’s processes.

Question 6

Cells Examples

Answer 6

White blood cells (protect body from infectious disease)

Neurons (transmit information to other nerve cells, muscles and glands)

Question 7

Tissues

Answer 7

Group of cells that have a similar structure and function together as a unit.

Question 8

Tissue Examples

Answer 8

Muscle Tissue: shorten or contract to produce movement
Nervous Tissue: coordinating and controlling body activities
Connective Tissue: connects or separates all other tissue in body

Question 9

Organs

Answer 9

Collection of tissues that structurally form a functional unit specialized to perform a specific function.

Question 10

Organ Examples

Answer 10

Heart (pumps blood and oxygen around body)
Brain (controls all body functions)
Stomach (digest and store food)

Question 11

Body Systems

Answer 11

Biological system consisting of a group of organs that work together to perform one or more functions.

Question 12

Body Systems Examples

Answer 12

Nervous System: communication to parts of the body
Urinary System: excretion of wastes
Digestive System: breakdown of food

Question 13

Homeostasis

Answer 13

Homeostasis is a self-regulating process by which biological systems maintain a stable internal environment (within cells) while adjusting to changing external conditions.

Question 14

Homeostasis Examples

Answer 14

Vasoconstriction and vasodilation, the widening and narrowing of blood vessels. They widen to carry more heat to the surface and vice versa

The urinary system maintains blood and water homeostasis by filtering out waste substances and uses the right amount of water to maintain homeostasis.

Question 15

Feedback Loop

Answer 15

Here are feedback loops:

1. Stimulus (start)
2. Receptor
3. Modulator (control centre that processes information)
4. Message
5. Effector (carries out the response)
6. Response
7. Feedback

Question 16

Negative Feedback

Answer 16

Negative feedback aims to negate/reverse a change in the internal environment.

Question 17

ATP

Answer 17

ATP (Adenosine Triphosphate) is the cell’s energy source. It captures chemical energy obtained from the breakdown of food and releases it to fuel other cellular processes.
An energy carrying molecule
Found in all living things

Question 18

Active Transport

Answer 18

Lower to higher concentration - against concentration gradient (up)
Require the cell’s energy (ATP) for the transfer to occur
Only occur in living cells
→ Cytosis

Question 19

Passive Transport

Answer 19

Passive Transport
Higher to lower concentration
Do not expend any energy (physical process)
Occur in living and dead cells
Almost impossible to prevent
	→ Diffusion
	→ Facilitated Diffusion
	→ Osmosis

Question 20

Cell Membrane Functions

Answer 20

Holds different components of the cell together
Protects the cell from the environment outside the cell
Regulates what enters and exists so that it doesn’t lose too many nutrients or take in too many ions

Question 21

Cell membrane qualities

Answer 21

Cell membranes are differentially permeable (semi-permeable)
Some ions and molecules can pass through but others cannot based on size and polarity (distribution of electrons in a molecules or compound)

Question 22

Cell Membrane Composure

Answer 22

Composed of proteins, cholesterol (regulator) and lipids arranged in 2 layers called the phospholipid bilayer

Question 23

Phospholipid heads

Answer 23

The head contains a phosphate molecules that is attracted to water (hydrophilic)
□ Negative polarity head attracts water

Question 24

Phospholipid tails

Answer 24

The two tails are made up of fatty acids (chains of carbon atoms) that repel water (hydrophobic)
□ Non-polar (uncharged)

Question 25

Chemical Polarity

Answer 25

Chemical polarity is a separation of electric charge leading to a molecule which has a negatively charged and a positively charged end. Water is polar.

Question 26

Diffusion

Answer 26

Diffusion is the net movement of molecules from an area of greater concentration to an area of lesser concentration. (with the concentration gradient) in order to reach dynamic equilibrium.

Question 27

Rate of Diffusion

Answer 27

□ Greater distance: diffusion is slower □ Higher temperature: diffusion is faster (more kinetic energy of molecules) □ Higher density of solvent: diffusion is slower □ Mass of substance: diffusion is slower □ Thinner barrier: faster diffusion □ Large surface area barrier: faster diffusion □ Higher concentration of substance: faster diffusion □ Nonpolar diffusion: diffusion is faster

Question 28

Osmosis

Answer 28

Osmosis is the diffusion of water molecules across a selectively permeable membrane from an area of higher concentration to an area of lower concentration in order to even out solute concentration.

Question 29

Hypertonic

Answer 29

The solution with the higher solute concentration

Question 30

Hypotonic

Answer 30

The solution with the lower solute concentration

Question 31

Isotonic

Answer 31

Solutions of equal solute concentration are isotonic

Question 32

Cytosis

Answer 32

Cytosis is an active process in which materials into and out of the cells using vesicles when there are a large amount or size of molecules.

Question 33

Vesicles

Answer 33

Vesicles are bubble-like structures consisting of a solid particle or a liquid droplet enfolded in a piece of the cell membrane.

Question 34

Small non polar molecules

Answer 34

Diffuse across the small gaps between lipids (oxygen and carbon dioxide)

Question 35

Fat-soluble non polar molecules

Answer 35

Diffuse across membrane by dissolving into lipid (alcohol & | steroid hormones)

Question 36

Small polar molecules

Answer 36

Diffuse across the phospholipid tails through the help of protein channels (facilitated diffusion) - slower process water can do this and also simply diffuse

Question 36

Small polar molecules

Answer 36

Diffuse across the phospholipid tails through the help of protein channels (facilitated diffusion) - slower process water can do this and also simply diffuse

Question 37

Large polar molecules

Answer 37

are unable to pass through the polar phospholipid heads without the extra help of facilitated diffusion via a carrier protein.

Question 38

Excretion

Answer 38

removal of wastes produced by metabolism within cells

Question 38

Excretion

Answer 38

removal of wastes produced by metabolism within cells

Question 39

Elimination

Answer 39

removal of undigested materials from the body

Question 40

Elimination

Answer 40

removal of undigested materials from the body

Question 41

Major excreted substances

Answer 41

carbon dioxide salts water urea

Question 42

Major excreted substances

Answer 42

carbon dioxide salts water urea

Question 43

Cortex

Answer 43

outside part, where the filtration occurs

Question 44

Cortex

Answer 44

outside part, where the filtration occurs

Question 45

Medulla

Answer 45

middle part, where substances are reabsorbed

Question 46

Medulla

Answer 46

middle part, where substances are reabsorbed

Question 47

Pelvis

Answer 47

inside part, where urine is collected before going down ureters