Chapter 1 - Science Of Life Flashcards Preview

Biology 2015-2016 > Chapter 1 - Science Of Life > Flashcards

Flashcards in Chapter 1 - Science Of Life Deck (27):
1

How long ago did life arise on earth?

Approximately 3.5 billion years

2

Describe the first organisms:

Single celled, the only life on earth for millions of years

3

Organisms change or ______ over long periods of time

Evolve

4

Today, millions of ______ of organisms exist on earth

Species

5

The ______ is the basis unit of life and makes up all ______

Cell, organisms

6

______ organisms are made of a single cell and are genetically ______ to their parent cell

Unicellular, identical

7

Many-celled organisms are called ______ and they may be made of ______ types of cells

Multicellular, different
All cells are not alike, have different characteristics

8

What is the size of a cell?

Very small, in general all are small, large organisms just have more organisms

9

Are cells organized?

highly organized even though they're chaotic

10

Specialized structures in cells are called ______

Organelles

11

What surrounds cells?

Plasma membrane

12

All cells must contain a set of ______ or DNA

Instructions
Tells the cell how to do its role + reproduce, genetic coding

13

Organisms maintain stable internal conditions called ______

Homeostasis
Very stable internal conditions

14

Example of homeostasis:

Temperature, water content, blood sugar, etc.

15

For a species to continue, some of its members must be able to ______ and pass on their traits to their ______

Reproduce, offspring (inheritance)

16

What does DNA stand for?

Deoxyribonucleic Acid, genetic information in all cells

17

DNA's instructions are called ______ and code for the complex ______ necessary for life

Genes, proteins

18

______ cells or body cells each have a full set of DNA or hereditary information from ______ parents

Somatic, both
Not every cell uses the coding they have

19

______ reproductions combine hereditary information from ______ parents

Sexual, both
Two different organisms combined

20

When a sperm and egg join, a fertilized egg or ______ forms and contains DNA from ______ parents

Zygote, both

21

In ______ reproduction, only a single parent cell reproduces and the new cells are genetically ______ to each other and the original cell.

Asexual, identical

22

______, not individual organisms, change or evolve over many generations

Species

23

______ ______ is the driving force for evolution

Natural Selection
Pushes better organisms to reproduce

24

According to natural selection, which individuals in a population are more likely to survive and be able to reproduce?

Organisms with favorable traits, "survival of the fittest"

25

A change in population due to the survival & reproduction of organisms with favorable traits is known as what?

Survival of the fittest

26

Define ecology:

Interaction of organisms with one another and with their environment

27

Three things that organisms need from their environment:

Nutrients, water, and gases