Bio SL A1.1

Where was the first cell created?

In water

What is the medium for life?

Water

What is water made up of?

One oxygen and two hydrogen held together by polar covalent bonds

What is one of the most important aspects of water?

Water molecules are polarized

Why is water polar?

Because of its asymmetrical structure and polar covalent bonds

What does polar/polarized mean?

A molecule contains uneven distribution of charges

What does dipole mean?

An uneven distribution of charges creating slightly positive and slightly negative poles

What is electronegativity ?

The measure of an atoms ability to attract shared electrons to itself within a covalent bond.

What factors do electronegativity rely on?

Atomic size and effective nuclear charge. More protons = stronger pull

How can you tell if a molecule is polar

By drawing a straight line through the molecule that separates positive and negative charges

What is VSEPR theory?

Valence shell electron pair repulsion theory explains that electron pairs try to repel eachother, therefore they try to get as far away as possible from to minimize repulsion.

Why is VSEPR theory important in the the context of water

Valence shell electron pair repulsion theory is important as it explains the V shape of water molecules.

What is cohesion

The ability of water molecules to attract and stick to eachother

What is cohesion due to

Cohesion is due to the polarity of each water molecule and the formation of hydrogen bonds.

What is a xylem

Specialized pathway for water and nutrients for plants

What is the definition of transpiration

A plant loosing water vapor from their leaves, stems, and flowers through their stomata.

What is adhesion

Waters ability to stick to other surfaces or molecules.

What is surface tension?

Surface tension is caused by strongly bonded hydrogen bonds between water molecules

What is capillary action

The movement of water within tight or small spaces due to the forces of adhesion and cohesion and surface tension

What does hydrophilic mean

Water loving molecules attracted to waters polarity. able to mix, dissolve and be attracted by water.

Solvent

The thing dissolving the solvent

Solute

The thing doing the dissolving

Why is water a versatile solvent

Waters polarity allows it to attract and break apart a wide range of molecules

What is metabolism

The sum of chemical reactions occurring within the body

Specific heat

Energy required to raise the temperature of a substance by 1 Celsius

What is waters specific heat?

4.186 J/g C

How much more energy is needed to heat water in comparison to air?

4x more energy

What is buoyancy

Ability to float on water. Reliant on density

Thermal conductivity

Rate heat can move through material

Viscosity

Ability to flow

What is a covalent bond

Sharing of valence electrons

What is a functional group

A chemical group with distinct properties that behave differently in chemical reactions

What are the 7 functional groups in chemistry

Hydroxyl, carbonyl, carboxyl, amino, sulfhydryl, methyl, phosphate

Catabolic reactions

Breaking bonds between molecules, breaking down molecules

Anabolic

Forming bonds between molecules

Dehydration/condensation synthesis

Taking away water to make bigger molecules. When two larger molecules fuse, in the process loose a smaller molecule

Hydrolysis

Adding water to break large molecules

Endergonic

type of metabolic reaction that forms bonds between molecules. Requires energy. Dehydration synthesis, anabolic reactions

Exergonic

Breaking bonds between molecules. Hydrolysis, digestion, catabolism

Amylose

Linear polysaccharide made of repeating alpha glucose units by a 1-4 glycosidic bond.

Amlopectin

Branched polysaccharide

What type of bonds does starch have in between their molecules?

1 – 4 glycosidic bonds

What type of glucose do starch use

Alpha glucose

What is a glycoprotein and its function

A sugar protein attached to an oligosaccharide used for cell recognition and immunity.

What are oligosaccharides

Macromolecules attached to a glycoprotein