Biology 1025 units 1-3

Biology

The scientific study of life

Respiration

Exchanging of gases between an organism & their environment. As well as releasing stored energy in stored food

Reproduction

Organisms reproduce their own kind

Sexual reproduction

Requires that two cells (sperm and egg) unite to produce the first cell of the new organism

Asexual reproduction

A single organism can reproduce without the aid of another

Growth

A progression from a simple form to a more complex one. Controlled by inherited DNA

Metabolism (energy processing)

Use chemical energy to power activities and chemical reactions

Response to the environment

Ability to respond to environmental stimuli

Homeostasis (regulation)

Ability to control internal environment to sustain life

Evolutionary adaptation

evolve over generations as individuals with traits best suited to their environment have greater reproductive success and pass their traits to offspring

Cell

The smallest unit of organization in a living thing

Cytology

Study of the cell

Ecology

The interaction of organisms with their environment and with eachother

Entomology

Study of insects

Mycology

Study of fungi

Physiology

The process and functioning of organisms

Taxonomy

The naming and classification of organisms

Zoology

Study of animals

Macromolecules

The structure and function of living things. Carbs, proteins, lipids, and nucleic acids

Chemistry

living things are composed of atoms. Atoms chemically bond to form elements, compounds, molecules, and macromolecules

Physics

Instruments like microscopes and x-rays, used to study living things, based on property of light

Computer science

Databases store info regarding proteins, genes, etc. Making the information easily available. Used in gene mapping and sequencing

Mathematics

Used for the study of populations for estimating population size and density, to describe how molecules move into and out of cells, etc

The scientific method

Observation, question, hypothesis, prediction, test/experiment, conclusion

Observation

Observe or notice some phenomena occuring around you

Question

The observation lands you to ask why or how the phenomena is occuring

Hypothesis

Your best guess of the answer to your question based on your acquired scientific knowledge

Prediction

If you manipulate a variable in the experiment, then what is the expected outcome

test/experiment

Carry out the action suggested by the prediction

Conclusion

The hypothesis was supported or the hypothesis was not supported (revise hypothesis or propose new one)

Biochemistry

Combines biology and chemistry, Studies the activity and properties of the molecules important to cells and other biological systms

Atoms

The smallest unit of matter

Molecules

Made up of one or more atoms. The atoms can be the same or different

Elements

Substances that cannot be broken down by chemical means into other substances

Bulk elements

Make up most of living cells

Trace elements

Required in tiny amounts

Human body

96% composed of carbon, hydrogen, oxygen, and nitrogen

Goiter

An enlarged tyhyroid gland, caused by an iodine deficiency

Compounds

Substances that contain two or more chemically combined elements

Chemical reactions

Chemical bonds break and new bonds form The breaking of bonds releases energy, the creation of bonds uses energy

Organic compounds

Contains carbon. Carbs, lipids, proteins

Inorganic compounds

Does not contain carbon

Structure of water

Two hydrogen atoms are joined to one oxygen atom by single covalent bonds

Adhesion

Causes water molecules to stick to the inner surface of a glass tube or a water-conducting vessel in a plant

Hydrophilic

Substance that dissolves in water (water-loving)

Hydrophobic

Substances that does not dissolve in watter (water-fearing)

Properties of Acids

Taste sour. Change litmus from blue to red. Their aqueous solutions conduct electric current (are electrolytes)

Properties of Bases

Taste bitter, feel slippery or soapy. Turn red litmus back to blue. Their aqueous solutions conduct and electric current (are electrolytes)

PH scale

Describes the acidity of a solution. Ranges from 0-7-14. The lower the number, the more acidic

Effect of pH on cells

Most cells and their contents function best in neutral pH levels, close to 7

Changes in pH could result in death of a cell

Buffer systems

Pairs of weak acids and bases that are present in biological fluids that prevent harmful changes in pH by:

accepting H+ ions if pH rises too high

releasing H+ ions if pH drops too low

Catabolic reaction

broken down into smaller components. Energy is released, breakdown of ATP

Anabolic reaction

Energy is used. Two simpler substances together to build more complex molecule

Monomer

Small molecules, sub-units

Polymer

Chain-like molecules, smaller molecules linked together

Macromolecules

Giant molecules, polymers. (carbs, proteins, nucleic acids)

Dehydration

(condensation)

Removes water from 2 molecules to make longer polymers

Hydrolysis

Water is added between a larger molecule to form two smaller molecules

Carbohydrates

Biomolecule composed of carbon, hydrogen and oxygen atoms

2 kinds - simple and complex

Simple carbohydrates

Simple sugars

Monosaccharides - monomers & single sugars

Disaccharides - two sugars or monosaccharides

Complex carbohydrates

Polysaccharides formed from simple carbs

Glucose

Found in sports drinks

fructose

Found in fruit

Monosaccharides

Single sugars

Disaccharides

A double sugar formed from two monosaccharides. A dehydration reaction is needed for the formation. (table sugar, sucrose)

Polysaccharides

Complex carbs. Long chains of simple sugars. 2 main functions: store sugar which cells use for energy & structure - provide protection and give shape

Lipids

Consists largely of the molecule triglyceride (combination of glycerol and 3 fatty acids.

Perform essential functions in the human body: energy storage, cushioning, and insulation. Unsaturated have less than the maximum # of hydrogen bonded to the carbons and saturated have the maximum amount

Proteins

Polymers constructed from amino acid monomer. Perform most of the tasks the body needs to function

Amino acids

All proteins are constructed from a common set of 22 kinds of this.

each consists of: a central carbon atom bonded to a hydrogen atom, a carboxyl group, an amino group, and a side chain also called an R group

Proteins as polymers

Cells link amino acids together by dehydration reactions. The resulting bond between them is called a peptide

Primary structure

Based on the specific sequence of amino acids in a protein

Secondary structure

Localized areas of cells, sheets, and loops within a peptide

Tertiary structure

Overall shape of one polypeptide

Quaternary peptide

Overall protein shape that results from interaction between the multiple polypeptides that make up the functional protein

Spontaneous generation theory

• maggots appearing from meat

• frogs and salamanders from mud

• mice from sweat and wheat

• scorpions from basil leaves

• living from non living

Francesco Redi

Hypothesized only flies would produce more flies. Placed rotting meat in jars (uncovered, covered (lid and gauze)

The maggots do not appear on meat if flies cannot land on it

Louis pasteur

Used heat to kill microorganisms in a flask. Showed even in the presence of air, microorganisms do not arise in heat-treated broth

Robert Hook

Designed a simple microscope. Described structures too small to be seen with the naked eye. Viewed cork and called the little boxes he saw cells

Robert Brown

Observed dark regions in cells (nucleus)

In 1838 & 1839, all plants and animals were described as being made of cells. This lead to the cell theory

The cell theory

1. all organisms are made up of one or more cells

2. cells are the basic units of function in all living things

3. all cells come from other existing ones

4. the activities of a multicellular organism depend on the activities of all of its cells

Quality of a microscope is linked to important features

• magnification

• resolving power

• depth of field

magnification

the number of times larger the image is, as compared to the actual specimen

resolving power

the ability of the microscope to show details at a given magnification. good resolution shows sharp, easily distinguished details

depth of field

the range that is in focus from foreground to background

Compound light microscope

light passes through the specimen. lenses enlarge, or magnify the image. can be used to examine stained or unstained samples

transmission electron microscope (TEM)

Specimens are embedded in plastic, sliced into thin sections and stained with heavy metal. shines beam of electrons through specimen to produce 2D image

Scanning electron microscope (SEM)

specimens are cleaned, preserved, and coated with a thin layer of metal or carbon. shines narrow beam of electrons over specimen, thereby knocking secondary electrons from specimens to produce a 3D image

fluorescense microscopy

can be used to examine naturally fluorescent specimens or specimens stained with fluorescent dyes. shines ultraviolet radiation on specimens to make them fluoresce

Atomic force microscopy

Metal and diamond probe scans surface or specimen, responding movements of probe are used to produce 3D image in near atomic detail. No special prep needed

Plasma membrane

Separates the living cell from its non-living surroundings. Regulates what moves into and out of the cell

Cell walls

Made up of tough fibres, mainly cellulose. Surrounds the plasma membrane, supports the cells and helps maintain their shape. Keeps the cells from absorbing too much water

Organelles

Structures in cells that perform a specific function

Cytoplasm

A cells contents

Cytosol

A jelly-like fluid in which all the organelles in a cell are suspended

Nucleus

Contains chromosomes composed of DNA. Store information necessary to produce proteins. Controls cells activities

Pores

Allow materials like RNA, to pass in or out of the nucleus. Contains one or multiple nucleoli where ribosomal RNA is made

Ribosomes

produced in the nucleolus. Responsible for building protiens. Some are free in the cytoplasm and others are attached to the rough endoplasmic reticulum

Endoplasmic reticulum (ER)

Membranous maze of tubes and chambers. Connected to the nucleus. Composed of smooth and rough ER

Smooth endoplasmic reticulum

Membrane-bound organelle found in eukaryotic cells that lacks ribosomes on its surface and is primarily responsible for synthesizing lipids, metabolizing carbs, and detoxifying chemicals

Rough endoplasmic reticulum

Membrane-bound cell organelle responsible for producing, folding, and processing proteins