Cell theory 1.1

Question 1

According to the cell theory… 3 points

Answer 1

1. Living organisms are composed of cells (or cell products)
2. The cell is the smallest unit of independent life
3. Cells can only arise from pre-existing cells

Question 2

Caveats to the cell theory include: 3 points

Answer 2

• Striated muscle – composed of fused cells that are multinucleated
• Giant algae – unicellular organisms that are very large in size (~7 cm)
• Aseptate hyphae – lack partitioning and have a continuous cytoplasm

Question 3

Organisms consisting of only one cell carry out all the life functions in that single cell: list all functions of life MRSHENG

Answer 3

• Metabolism
• Reproduction
• Sensitivity
• Homeostasis
• Excretion
• Nutrition
• Growth

Question 4

What do cells need to do in order to produce chemical energy required for survival (via metabolism)

Answer 4

Materials from the environment

Question 5

The rate of metabolism is a function of?

Answer 5

A cell’s mass/volume

Question 6

The rate of material exchange is a function of?

Answer 6

a cell’s surface area

Question 7

How does surface area to volume ratio limit the cell size

Answer 7

Keeps the cell small in size to keep a large Surface area: VOL ratio. This will have a decreased metabolic rate and an increased material exchange increasing survival chances.

Question 8

Magnification formula (MIA)

Answer 8

Magnification = Image size/Actual size

Question 9

Calculating Actual size (AIM):

Answer 9

Actual size = Image size / Magnification

Question 10

Types of microscopes

Answer 10

1. Light Microscopes
2. Electron microscopes

Question 11

Light microscopes

Answer 11

• use lenses to bend light
• Can view living specimens in natural colour
• Have lower magnification and resolution

Question 12

Electron microscopes

Answer 12

• use electromagnets to focus electrons
• Can only view dead specimens in monochrome
• Have higher magnification and resolution
• Can show cross-sections (TEM) or surface renderings (SEM)

Question 13

In multicellular organisms:

Answer 13

• Cells may be grouped together to form tissues
• Tissues may interact to form functional organs
• Organs may combine to form body systems

Question 14

Emergent Properties

Answer 14

Emergent properties arise from synergistic interactions between
the individual cells to produce entirely new aggregate functions. eg: Increased levels of antibiotic resistance in bacterial biofilms