Honors Biology - Chapter 1

gene

a segment of DNA that carries the genetic code to make a specific polypeptide chain

organism

any individual living thing

cell

a basic unit of structure and function of living things

science

a body of knowledge that explains the natural world

hypothesis

an explanation or answer that can be tested (by experiment, further observations, or evidence)

steps of the scientific method

1. make observations

2. ask a question

3. form a hypothesis

4. test the hypothesis

5. draw conclusions

6. communicate results

experiment

a scientific investigation that is performed under controlled conditions

manipulated (independent) variable

the thing you change

responding (dependent) variable

what you observe/measure

data

information gathered from observations

quantitative

a quantity, number, or measure

qualitative

a quality, description

bar graphs

used to compare values

line graphs

usually show trends or change over time

scientific theory

explains overall phenomena and is supported by evidence

theory

explanation

law

statement that predicts or tells us what we are to expect to happen

metabolism

sum of all the biochemical reactions in an organism

positive feedback

when a variable is intensified or increases the occurrence of events

Robert Hooke

first to look at cells through a mircroscope

light microscope

to see small details of a specimen

transmission electron microscope (TEM)

views things up to 2 million times with a clear image, but can only be used to view very thin slices

scanning electron microscope (SEM)

used to find the shape and surface texture of small objects

scanning acoustic microscope

uses sound waves to scan a specimen

negative feedback

when a variable triggers a counteracting response to return to a set point

spontaneous generation

the idea that living things came from nonliving things

Francisco Redi

• 1668

• experiment with red meat (covered/uncovered)

  • flies laid eggs

  • maggots appeared

Spallanzani

* gravy experiment (covered/uncovered)
* bacteria multipying

Louis Pasteur

• 1800s

• heated s-shaped flask

• bacteria

8 characteristics of living things

• cell(s)

• reproduction

• genetic code

• growth and development

• use energy

• response to environment

• internal balance

• evolution

cell

the smallest unit of life

unicellular

single-celled

multicellular

multi-celled

sexual reproduction

mixes DNA from two parents

asexual reproduction

DNA from a single parent (cloning, budding, regeneration)

genetic code

directions for inheritance

growth

getting larger

development

changing shape and structure

differentiation

cells look different and perform different functions/the process by which a cell becomes specialized to perform a specific function (by activating and deactivating genes)

metabolism

chemical reactions in the body

heterotroph

animals eat to obtain energy (ATP)

autotroph

plants photosynthesize

stimulus

a signal picked up by a sensor/receptor

response

a reaction to the stimulus (caused by an effector)

homeostasis

maintaining constant internal conditions (sameness)

evolution

species changing over time

zoology

the study of animals

paleontology

the study of ancient life

cytology

the study of cells

botany

the study of plants

entomology

the study of insects

microbiology

the study of microorganisms

ecology

the study of the relationships among living organisms

anthropology

the study of the origin and development of human societies and cultures

levels of organization of living things

1. atom
2. molecule
3. organelle
4. cell
5. tissue
6. organ
7. organ system
8. organism
9. population
10. community
11. ecosystem
12. biome
13. biosphere
14. biodiversity

biodiversity

the variety of organisms living in a habitat, ecosystem, etc.

scientific investigation

plan for asking questions and testing possible answers

observation

anything detected with the senses, which include sight, hearing, touch, smell, and taste

falsifiable

able to be proven false by an observation or experiment

prediction

a statement that tells what will happen under certain conditions

evidence

any type of data that may be used to test the hypothesis

cell theory

theory that states all living things are made up of cells, all life functions occur within cells, and all cells come from pre-existing cells

germ theory

scientific theory that proposes that microorganisms are the cause of many diseases

natural selection

evolutionary process in which organisms best suited to their environment are more likely to survive and pass on their traits to future generations