Biology 11: Unit 1 - What is Biology

A hypothesis is

An educated guess/possible explanation for natural phenomenon

The Body Tube

Holds the ocular lens the correct distance from the objective lens

Objective Lenses

Name of the lenses closest to the specimen being viewed

Problem

People on Java are dying of Beriberi

If the experiment data supports the hypothesis

Repeat experiment for validation Make predictions Develop new hypothesis Report our findings in scientific literature

What are the characteristics of all living things?

- reproduction = asexual & sexual - produce waste (need for energy) - communication - growth and development (specialization of cells or structures) - death - cells (building blocks of life) or 1 cell - breathe - water needs - food (eat or make) - use energy - maintain a stable internal environment (homeostasis = endothermic & exotherm) - detect and respond to external stimuli (physical, smell, sound, heat) - can engage in movement (may occur internally or even at a cellular level) - all organisms have a nuclei acid (DNA, RNA) as the hereditary molecule - all organisms are adapted to living in their environment - exhibit complex organization (cells, tissues, organs, organ systems) - populations of organisms exhibit change over time due to mutation and natural selection (eg. Viruses can reproduce quickly, especially if they hijack other cells)

What is Science?

- study of living and non-living things - process of gathering information - observation and experimentation

Care of the microscope

1. Carry with both hands, one beneath the base and one holding the arm 2. Carry in an upright position 3. Store with the low power lens in position. Remove any slides first 4. Never touch any lenses with your fingers 5. Only use lens paper to clean lenses 6. Always examine your specimen under lowest power first. When the object is centred and in focus, switch lenses to a higher power 7. Never use the coarse adjustment knob for any objective lens except the low power lens

Steps in the Scientific Method

1. Observation of the natural universe 2. Define a problem or ask the question, "why do I Observe...?" 3. State a hypothesis (educated guess - possible/testable explanation) 4. Test hypothesis with an experiment 5. Analyze results 6. Adjust our hypothesis accordingly

A theory is

A substantial concept that has broad scientific support: the closest thing to a scientific law Has been repeatedly tested Predictions are based on theory

Experimental Procedure

A. Only 1 hypothesis is tested at a time B. Work with variables (3types): - Manipulated variable - is INTENTIONALLY changed during experiment - Response variable - is MEASURED as it changes in response to the manipulated variable -Controlled variable - factors that are kept the same between experimental groups C. The experiment must be repeatable

Experiment control

Chickens are fed white rice

Experimental group

Chickens fed with wild rice

Collect and analyze data

Chickens fed with wild rice are healthy Chickens fed with white rice still get beriberi and die

Diaphragm

Controls the amount of light passing through the microscope slide

Hypothesis

Eating brown rice prevents beriberi

Total magnification

Found by multiplying the ocular lens magnification by the objective lens magnification

Dependant/responsive variable

Get sick with beriberi

Magnification

High school microscopes have 3 magnifications. Each objective lens has the magnification written on it. The ocular lens further magnifies the object being viewed.

Revise hypothesis/design further experiments

Isolate substance preventing beriberi

Controlled variable

Location of chickens Amount of food Chickens are used as subject Who feeds them

Coarse Adjustment

Makes large changes to the position of the objective lenses in order to bring the specimen being viewed into focus

Fine Adjustment Knob

Makes small changes to the position of the objective lenses. Should be used when focusing under medium or high power

Words or phrases that define what scientists do?

Paperwork Observe and experiment Study for the furthering of knowledge Studying rocks

If the hypothesis is NOT supported

Rewrite the original hypothesis

Revolving nose piece

Rotates to place the objective lenses into position

A. What is Biology?

Study of living organisms divided into many specialized fields that cover Morphology ( form and structure of organisms), Physiology (normal functions of organisms and their parts), Anatomy (body structures of organisms), Behaviour, Origin and Distribution.

Arm

Supports the body tube. Your hand should be put here when moving your microscope to another location

Base

The bottom of the microscope, where you should always put one hand before carrying the microscope anywhere

Lamp

The light source for the microscope

Stage

The platform beneath the objective lenses on which the microscope slide is placed

B. What is the Scientific Method?

The process of science

Independent manipulative variable

Type of rice

Stage Clips

Used to hold the microscope slide in position

Conclusions

Wild rice contains something that prevents beriberi