Chapter 2

Question 1

Movement

Answer 1

All living things are capable of self-generated movement. Examples include individual bacteria swimming, humans walking, and plants moving towards light.

Question 2

Respiration

Answer 2

All living things can extract energy from carbohydrates, fats, and proteins through the biochemical processes of aerobic or anaerobic cellular respiration.

Question 3

Sensitivity

Answer 3

All living things sense and react to stimuli. An example is plant tips growing towards a light source.

Question 4

Growth

Answer 4

All living things grow and develop over time. An example is how infants grow into adults.

Question 5

Reproduction

Answer 5

All living things can produce new living things. Examples include cell division and sexual reproduction.

Question 6

Equilibrium

Answer 6

All living things can maintain a relatively stable internal environment unique to an individual species, known as maintaining homeostasis. This allows organisms to tolerate environmental changes such as varying temperatures or a lack of water availability.

Question 7

Excretion

Answer 7

All living things produce wastes that must be removed. Examples include urine or dead cells, which can become toxic if not removed.

Question 8

Nutrition

Answer 8

All living things extract nutrients from the environment, which are used to produce cellular energy, grow and develop, and maintain equilibrium. Some organisms gain nutrition by consuming food (heterotrophs), whereas others produce…

Question 9

Cell theory

Answer 9

All living things are made up of cells. Cells are the smallest and most basic units of life. All cells come from pre-existing cells.

Question 10

Prokaryotes

Answer 10

______ are organisms categorized by lacking a nucleus, having a single loop of circular DNA, and potentially containing smaller circular units of DNA called plasmids. They have a plasma membrane, cytosol, ribosomes, and DNA. They reproduce through binary fission.

Question 11

Eukaryotes

Answer 11

__________ are organisms categorized by having a nucleus, multiple linear chromosomes of DNA housed in the nucleus, and membrane-bound organelles. They tend to be larger than prokaryotes and have a plasma membrane, cytosol, ribosomes, and DNA. They reproduce through meiosis or mitosis.

Question 12

Six Kingdoms of Life

Answer 12

Animalia, Archaea, Bacteria, Fungi, Plantae, and Protista.

Question 13

Organelles

Answer 13

Compartments within a cell that have different structures and functions to increase cell efficiency.

Question 14

Plasma Membrane

Answer 14

The ______________ is a selectively permeable barrier between the intracellular and the extracellular environment. It is made of a phospholipid bilayer which is studded with many molecules.

Question 15

Cytosol

Answer 15

Fluid substance inside the cell that contains dissolved salts, nutrients, and molecules necessary for cell function.

Question 16

Nucleus

Answer 16

The ______ is surrounded by a double membrane. Its role is to protect and confine the genetic information (DNA) of the cell. Inside the _______ is a smaller structure known as the nucleolus which is the site of ribosome production.

Question 17

Ribosomes

Answer 17

________ are tiny structures made of ribosomal RNA (rRNA) and proteins that fold into a large and small subunit. Cells have many _________, which either float freely in the cytoplasm or are attached to the rough endoplasmic reticulum. __________ assemble the building blocks to make proteins. Not membrane-bound.

Question 18

rough endoplasmic reticulum

Answer 18

A membranous chain of connected and flattened sacs which are coated with ribosomes. This allows the ___________ to synthesise and modify proteins. The ______________ typically surrounds, or is close to, the nucleus.

Question 19

Smooth endoplasmic reticulum (SER)

Answer 19

A membranous chain of connected and flattened sacs which are not coated with ribosomes. The _______ is responsible for the production of lipids in a cell.

Question 20

Golgi apparatus/Golgi body

Answer 20

Stacked flattened sacs that are the sites of protein sorting, packaging, and modification for use in the cell or export. Protein-filled vesicles often fuse with or bud off from the __________.

Question 21

Lysosome

Answer 21

A membrane-bound vesicle that contains digestive enzymes. It is responsible for breaking down cell waste and toxins, acting like a garbage disposal.

Question 22

Mitochondria

Answer 22

An organelle with a highly folded inner membrane surrounded by a second outer membrane. ___________ are the site of aerobic cellular respiration, a chemical reaction that produces the ATP required to power cellular processes. They also contain their own DNA and ribosomes.

Question 23

Chloroplast

Answer 23

A double membrane-bound organelle that contains flattened, fluid-filled sacs that are the site of photosynthesis. ___________ also contain their own DNA and ribosomes.

Question 24

Vacuoles

Answer 24

A membrane-bound sac that is used for water and solute storage. _________ can also play a role in maintaining plant cell structure. Not membrane-bound.

Question 25

Cell wall

Answer 25

A sturdy border outside the plasma membrane that provides strength and structure to plant, bacterial, and fungal cells. Not membrane-bound.

Question 26

Vesicle

Answer 26

A small, membrane-bound sac that transports substances into or out of a cell, or stores substances within a cell.

Question 27

Cytoskeleton

Answer 27

A large network of protein filaments that start at the nucleus and reach out to the plasma membrane. The ____________ is critical for maintaining shape and transporting vesicles around the cell. Not membrane bound.

Question 28

Mitochondria Structure

Answer 28

Mitochondria consist of an outer membrane and a highly folded inner membrane.
The inner membrane folds are known as cristae.
This structure creates a narrow, low-volume intermembrane space.
The space inside the inner membrane is called the mitochondrial matrix.

Question 29

Mitochondria Function

Answer 29

Cellular respiration is the cell’s primary method of producing energy.
It breaks down glucose, a simple carbohydrate, to generate energy.
Cellular respiration can occur aerobically or anaerobically.
Mitochondria specifically play a role in the aerobic cellular respiration pathway.

Question 30

formula for aerobic cellular respiration

Answer 30

glucose + oxygen —-> carbon dioxide + water + energy

C6H12o6 + 6O2 —-> 6CO2 + 6H20 + 36 ATP

Question 31

Differences in plant/animal cells

Answer 31

A cell wall (made up of cellulose) is present in plant cells, but not animals. Chloroplasts for photosynthesis are in plant cells but not animals. In animals, vacuoles tend to be small and there can be many or none, whereas plants usually tend to have one large vacuole.

Question 32

Why are cells so small?

Answer 32

By having many small cells, as opposed to one big cell, it is more efficient to transport nutrients and remove wastes. The benefits of having small cells are:
1 The exchange of materials with the extracellular environment (including importing nutrients and oxygen, and removing toxins) can occur efficiently and effectively due to a high surface area to volume ratio. This will be explained later in this lesson.
2 Distances to travel within the cell are smaller, so the intracellular transport of molecules is faster.

Question 33

Volume

Answer 33

_____ is the space within an object.
1mL=1cm^3
______= length x width x height

Question 34

Surface area

Answer 34

________ is the sum of the area of each of the faces of a three-dimensional object. Always measured in units^2, (e.g. cm^2 or m^2).

Question 35

SA:V

Answer 35

To calculate the SA:V of an object we must take the following steps:
1 Calculate surface area
2 Calculate volume
3 Calculate (surface area)/(volume) to work out every unit of surface area per unit of volume
4 Convert into a ratio.

Surfaces, which are made up of many cells, are able to exchange substances with the environment most effectively if they have a high SA:V. Therefore, both surfaces and
cells that need to transport lots of substances across their border tend to be small
and elongated. For instance, in the small intestine, which is responsible for absorbing nutrients, cells lining the intestine arrange into ‘finger-like’ shapes called villi.