Unit One - Chapter 2 + Notes Flashcards Preview

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Flashcards in Unit One - Chapter 2 + Notes Deck (30):

What is a controlled experiment?

An experiment in which only one variable is being tested.


What is the variable factor?

The factor being tested.


What group involves the variable factor being tested?

The experimental group.


What is the control group?

The group that is completely identical to the experiment group but doesn't include the variable factor.


How many kingdoms can algae be found in?

3 out of 5.


What are the 5 levels of organization?

Cells > tissue > organs > systems > organism.


What is a characteristic of a multicellular organisms cell?

The cells are highly specialized for particular functions. Example: human nerve cells


What do the two basic components of the cell theory state?

1) cells, or products made by cells, are the units of structure and function in all organisms
2) all cells come from pre-existing cells


Who is Leeuwenhoek?

A Dutch civil servant who designed a microscope to study bacteria and structures in small insects, etc. (year- 1650)


Who is Hooke?

An Englishman who made microscopes. He examined a cork layer and observed rows of compartments. These compartments became known as cells. (Year- 1600s)


Why did Hooke call the cork compartments cells?

They reminded him of cells in which monks lived in medieval monasteries.


What are 4 points to describe prokaryotes?

•don't have a membrane enclosing their DNA
•lack organelles
•very small (1-10um)


What are 4 points to describe eukaryotes?

•usually have at least one membrane enclosed structure, the nucleus, which contains DNA
•contain organelles
•usually much larger than prokaryotes (10-100um)
•plants, animals, fungi, Protista kingdoms


Lamarck's Hypothesis:
1) _________present
2) Changes in _________
3) _______ _______ in response to the _____________
4) ___________ survive

1) organisms
2) the environment
3) organisms change, environment
4) all organisms


Darwin's hypothesis:
1) Populations of _________ with _______ present
2) _______ in the environment
3) organisms with _______ _______ are _______ ________
4) ________ ________ survive

1) Organisms, variations
2) changes
3) certain features, naturally selected
4) certain organisms (best fit)


What are unicellular organisms?

Organisms that contain only one cell.


Define evolution

Change through time. Is the biological process that links all species


Define species

Organisms that are so close together, they can mate and produce offspring


List 3 basic ways distinctness is maintained in species

Behavioural - wolf and fox
Geographical - Polar bears and Grizzly Bears
Physical differences - Great Dane and chihuahua


What is reproductive isolation?

The inability of groups to interbreed successfully


Define variations as they relate to evolution

Difference among individuals of the same species.
Ex: some dogs are big and some are small


What is artificial selection? One example

Human intervention on the breeding of organisms with desirable traits
Ex: horses > pure bread with pure bread


What is natural selection? One example

A population with most successful adaptation to their environment will reproduce.
Ex: Giraffes > long necks can reach more food


Define adaptation in relation to evolution.

Characteristics of a species that enables them to survive and reproduce


Example of Lamark's theory of evolution

1. Giraffes have the same length neck
2. Change in environment gets them to change themselves like stretching their necks
3. Offspring have longer necks. Everyone survives


Example of Darwin's theory of evolution

1. Not all giraffes have the same length of neck
2. Change in environment allows giraffes with certain features to survive
3. Not all giraffes survive, only the best fit for the environment


What is the definition of a hypothesis?

A hypothesis is a statement that explains an observation.


What are light microscopes characteristics? (3)

Uses light passing through a thin specimen
Magnified through a lens system - 1500 times
Dyes are often helpful with this microscope


What are characteristics of a phase-contract microscope? (2)

Special type of light microscope that increases the did fence between light and dark, making structures more visible.
Important in the study of living cells and cell division.


What are characteristics of an electron microscope? (2)

Use electron beams rather than light beams to illuminate.
Enlarge structures as much as one million times to provide detail.