Chapter 1: Cells

Question 1

Proposes that all organisms are composed of one or more cells and, furthermore, that cells are the smallest unit of life.

Answer 1

Cell theory

Question 2

Discovered the cell

Answer 2

Robert Hooke

Question 3

Unicellular organisms carry out ______ _______ ________ ______

Answer 3

All the functions of life

Question 4

What is an important factor in limiting cell size?

Answer 4

Surface area to volume ratio

Question 5

What leads to new emergent properties and multicellular organisms?

Answer 5

Interactions between their cellular components

Question 6

Multicellular organisms have ___________ _________, which develop as a result of cell differentiation

Answer 6

Specialized tissues

Question 7

This results from the expression of some genes but not others

Answer 7

Cell differentiation

Question 8

These are able to divide and differentiate along different pathways and are essential for embryonic development

Answer 8

Stem cells (This ability makes them suitable for therapeutic uses)

Question 9

Who said cells can only come from pre-existing cells?

Answer 9

Louis Pasteur

Question 10

What are two examples of things that do not fit the cell theory perfectly?

Answer 10

Fungi because they have nuclei not divided into separate cells by cell walls

Skeletal Muscle

Question 11

What are the functions of life?

Answer 11

Metabolism 
Growth
Response 
Homeostasis 
Nutrition 
Reproduction 
Excretion

Question 12

The ability to control an internal environment

Answer 12

Homeostasis

Question 13

What is a paramecium?

Answer 13

They can be observed under a light microscope. They have cilia, which they flick in rhythmic waves to move about in water, and they also have a row of specialized cilia that waft food particles toward the oral groove.

Question 14

What is chlorella?

Answer 14

A photosynthetic organism with rapid growth rate. Although it’s cells are small and must be viewed with a microscope, it can quickly produce large numbers of individuals, which turn water green and opaque.

Question 15

They ability of the microscope to separate objects that are close together so that more detail can be seen

Answer 15

Resolving power

Question 16

The resolution of an ______ microscope is much better than that of a light microscope because of the shorter wavelength of electrons

Answer 16

Electron (it can magnify up to 500,000 times while the light can only do 2000)

Only nonliving material can be observed by an electron microscope

Question 17

What are the two types of electron microscopes?

Answer 17

The TEM (transmission electron microscope) and SEM (scanning electron microscope)

Question 18

What does the TEM microscope do?

Answer 18

It produces clear images of thin sections of material

Question 19

What does the SEM electron microscope do?

Answer 19

Electrons are bounced off objects to produce detailed images of their external appearance

Question 20

This is defined as the ratio of the size of the image to the size of the object

Answer 20

Magnification

Size of image
_______________ = magnification
size of object

Question 21

What does the volume of a cell determine?

Answer 21

The level of metabolic activity that takes place within it

Question 22

What does the surface area of a cell determine?

Answer 22

The rate of exchange of materials with the outside environment

Question 23

What is a genome?

Answer 23

The genetic make up of a cell

Question 24

What are embryonic stem cells?

Answer 24

Cells with the ability to differentiate into all the body’s cell types.

Question 25

How do stem cells differ from other cells?

Answer 25

1. They’re unspecialized
2. They can divide repeatedly to make large numbers of new cells
3. They can differentiate into several types of cell
4. They have a large nucleus relative to the volume of the cytoplasm

Question 26

A well established and widely excepted principle that arises from extensive observation of trends and discrepancies, and incorporates facts, laws, predictions and tested hypotheses

Answer 26

Theory

Question 27

A speculative, specific and testable prediction about what is expected to happen in an investigation

Answer 27

Hypotheses

Question 28

These have a simple cell structure with no compartmentalization

Answer 28

Prokaryotes (they also have no nucleus or organelles and are believed to be the first cells to have evolved)

Question 29

This surrounds the cell. It protects the cell from bursting and is composed of peptidoglycan, which is a mixture of carbohydrate and amino acids

Answer 29

Cell wall

Question 30

This controls the movement of materials into and out of the cell. Some substances are pumped in and out using active transport

Answer 30

Plasma membrane

Question 31

This is inside the membrane and contains all the enzymes for the chemical reactions of the cell. It also contains the genetic material

Answer 31

Cytoplasm

Question 32

This is found in a region of the cytoplasm called the nucleoid. The DNA is not contained in a nuclear envelope and is not associated with any proteins.

Answer 32

Chromosome

Question 33

These replicate independently and may be passed from one cell to another. They’re contained in small circles of DNA found in bacteria

Answer 33

Plasmid

Question 34

These are found in all prokaryotic cells, where they synthesize proteins. They can be seen in very large numbers and cells that are actively producing protein.

Answer 34

Ribosomes

Question 35

These have a compartmentalized cell structure with membrane-bound organelles present in the cytoplasm; they have a nucleus

Answer 35

Eukaryotes

Question 36

This is present in some prokaryotic cells. It projects on the cell wall, and enables a cell to move

Answer 36

Flagellum

Question 37

These structures, found on the cell wall, can connect to other bacterial cells, drawing them together so that genetic material can be exchanged between them.

Answer 37

Pili or pilus

Question 38

When a cells DNA replicates and separates into two different areas of the cytoplasm, which then divides into two

Answer 38

Binary fission