Bio Unit 1

Hydrophobic

Non-polar, water fearing, faces away from water

Hydrophilic

polar, water loving, attracted to water so it faces toward water

Carbohydrates

Organic compounds of carbon, hydrogen, and oxygen.

Carbohydrates General Formula

Cx(H2O)y

Monosaccharides

Simple sugars with 3-7 carbon atoms, monomers of carbohydrates

Function of Carbohydrates

- Fast energy source, being hydrophilic and polar the molecules are easy to break apart for quick energy

- Long term energy (can be stored then used later, but lipids are more efficient)

- Structural (Cellulose): inedible, used to build hard and sturdy material to hold the organism ( ex: bark)

Structural materials

Carbohydrates provide support in biological structures.

Recognition molecules

Carbohydrates that trigger biological responses in cells.

Functional group found in monosaccharides.

- Ether group

- Hydroxide group

Properties of Carbohydrates

-polar

-soluble in water

- hydrophilic

Starches

- Polysaccharides for long-term energy storage in plants

- made from alpha 1,4 glycosidic linkages

Glycogen

- Animal polysaccharide for energy storage with branching

- made from alpha 1, 6 glycosidic linkages and alpha 1,4 glycosidic linkages

Cellulose

- Structural polysaccharide

- made of beta- 1, 4 glucose in plants.

Amylose

- small part of starch

Dehydration/Condensation

- the reaction that takes place when linkages are formed (ex: monomer becomes either dimer or polymer)

-Water is a byproduct

Hydrolysis

- The reaction that breaks down linkages (ex: dimer or polymer breaks into monomers)

- Water is a reactant

Name an example of a monosaccharide

- glucose (used by plants and humans for energy)

- fructose (found in fruits)

- galactose ( used by human tissues, muscles)

- sucrose

- maltose

Name an example of a polysaccharide

- cellulose (structural)

- starch (used in plant energy storage)

-glycogen (human energy storage)

What is a triglyceride

- Large monomers

- made of glycerol and fatty acids,

Phospholipid

- modified lipid in which a phosphate group replaces a fatty acid

- amphipathic (phosphate group is polar, the rest of the lipid is not)

- the hydrophobic portion faces away from water, lines up together to create a stable structure

- The hydrophilic portion faces outside, charged and able to interact with water

Function of phospholipids

- used to create cell membranes

- Controls the flow water and molecules in and out of the cell (water and ions can only go through the limited phosphate heads, never through the tails, limiting the amount going in and out)

Structure determines. .

function

Lipids

-large molecules, not a polymer

- made of 3 fatty acids and a glycerol (triglyceride)

- can be wax, oils or fat

Functions of Lipids

- Long term energy storage (double the energy of carbohydrates per gram)

- Waterproofing (wax on feathers and fur)

- Insulation against heat loss

Ester Linkage

Bond between the glycerol and the carboxyl group of a fatty acid in a lipid

What is a fatty acid made of?

carboxyl group and a hydrocarbon chain

Saturated

A lipid with only single bonds

Monounsaturated

A lipid with one non-single bond (cis-double bond usually, creates a kink)

Polyunsaturated

A lipid with more than one non-single bond

Why are some lipids liquid and some solid at room temperature?

- Solid: saturated, single bonds cause it to be linear with no kinks, allowing them to stack closer together, creating stronger LDF bonds (Higher Ea), giving them a higher mp than room temp

- Liquid: unsaturated, in nature has a cis-double bond, creating a kink (bend) in the structure, preventing it from stacking close together and creating weaker LDF bonds (smaller Ea) and therefore lower mp which can be reached at room temp (trans has a less drastic kink, but is only created artificially and is rare due to it being harmful)

How does a phospholipid differ from a triglyceride?

phospholipid has a phosphate group instead of 1 of the fatty acids that triglyceride has

What role do phospholipids play in living systems?

- Forms a bilayer in the cell membrane that allows the cell to be selective about the amount of water and ions entering and exiting the cell

What is the difference between unsaturated triglycerides with a cis and trans double bond?

- Cis double bonds have the hydrogens on both sides on the same direction (both above or below the double bond), and create a bigger kink than trans double bonds, and are naturally found in nature

- Trans double bonds have the hydrogens on either side of the double bond facing opposite directions (one up one down), giving it a more linear structure than cis double bonds with a minimal kink. However they are not found in nature and only created artificially through hydrogenation, meaning the body is not equipped to break them down, leading to a lot of health problems when consumed.

Why are lipids not used as an immediate source of energy?

- Due to their long hydrocarbon chains that hold all the energy being hydrophobic (can't break down with water) and unbranched (no snippets to break off) the energy contained within them is not easily accessible

Is a fatty acid hydrophobic, amphipathic, or hydrophilic?

hydrophobic

What elements compose lipid molecules?

- C, H, O (P if its a phospholipid)

Why are lipids good at storing energy?

Because their hydrocarbon chains can hold a lot of energy in each bond

What kind of linkage(s) does glycogen have?

alpha 1,4 glycosidic linkage and alpha 1,6 glycosidic linkage

What kind of linkage(s) does cellulose have?

beta 1,4 glycosidic linkage

What kind of linkage(s) does starch have?

alpha 1,4 glycosidic linkage

What are the two differences between RNA and DNA?

- The 5 carbon sugar in DNA does not have a hydroxyl group attached while RNA does

- DNA has Thymine while RNA has Uracil

What is hydrogenation?

The process of converting unsaturated fats to saturated fats by adding hydrogen artificially

Function of the Golgi Apparatus

- To store and package vesicles received from the ER, tagging (modifying in a way? but minor change) them (with sugars and phospholipids)

- This ensures they will be transported to the correct spot

What are the different portions of the Golgi Apparatus?

- Cis (closest to the ER, entry here)

- Trans (furthest end, exit here)

What is the endomembrane system?

- A group of membranes and organelles working together to modify, package and transport lipids and proteins

- Only found in eukaryotes

What are the organelles and membranes involved with the endomembrane system?

- Nuclear Envelope

-ER

-Golgi Apparatus

- Lysosomes

- Vesicles

- Cell Membrane

Function of Endoplasmic Recticulum (ER)

- Modifies proteins

- Synthesizes Lipids (makes phospholipids for other cellular membranes)

What are the different parts of the ER, and what are they made of?

- Rough (close nucleus)

- Smooth (other side)

- Made of a network of membranous tubules and sacs

What is the hollow portion in the ER's tubules & discs called?

Lumen

What does the rough ER do?

- The ribosomes on its surface (gives its name) makes proteins

- These proteins are fed to the lumen (some transfer in fully, some are stuck in the membrane)

What happens to the proteins in the lumen?

- They are first modified

- Then either will be incorporated into a cell membrane (Can be ER or other organelles) or be secreted from the cell

What happens to proteins in the rough ER that are not needed in the cell?

They are packaged into vesicles and transported to the golgi apparatus ( phospholipids for other cells are also transported when this vesicle forms)

What cells are ER's more prominent in?

- Cells that need to secrete a lot of enzymes or other proteins

- Ex: Liver cells

What is the function of the smooth ER?

- Synthesizes of carbohydrates, lipids, and steroid hormones

- Detoxifies medicine & poisons

- Stores Calcium ions

sacroplasmic reticulum

- Special type of smooth ER found in muscle cells

- Responsible for storing Ca which allows muscle contraction

Transitional ER

- Tiny smooth patches on the smooth ER

- Where the vesicles from the rough ER exit from

What happens on the cis face of the golgi?

- vesicles from the smooth ER fuse into the cis face and let out their contents

- the contents enter the lumen of the golgi

What happens at the trans face of the golgi?

- the modified (tagged) proteins are packaged in the lumen into vesicles and sent out through the trans face

What are the two things that can happen to a vesicle leaving the golgi apparatus?

1) the vesicles deliver their package to another organelle for use

2) the vesicles fuse with the plasma (cell) membrane, secreting the contents outside

What kind of cells have a lot of golgi apparatuses?

- Cells that secrete digestive enzymes (salivary gland)

- Immune system cells that secrete antibodies

Lysosome

- specialized structure in the cell

- has enzymes inside to digest macromolecules for reuse (acidic)

-

What happens to the broken down bits of the macromolecules in a lysosome?

- They are secreted through the lysosome membrane and into the cytoplasm directly

How do lysosomes function?

By fusing with other membrane bound compartments storing food or other contents (ex: vesicles), then secreting enzymes inside that break the contents down.

What happens in the lumen of the golgi?

- the contents are modified (tagged) with sugars and phospholipids so that they can be delivered where they need to go

Passive Transport

No ATP required

Active Transport

uses ATP

Simple Diffusion

- Normal diffusion of particles following the [] gradient from high to low

- passive transport

- non-polar molecules and dissolved gases can go through this way

Facilitated Diffusion

- diffusion but either a carrier or channel protein is used to help the particles go through

Carrier Protein

- Bonds to the particle and changes shape to let the molecule out on the other side, returns to original shape when the molecule is removed

- Door, but only for one specific molecule (different depending)

Channel Protein

- protein with a "hall" or hollow tube in it that allows ions and charged molecules (including polar) to just past through

Osmosis

- Simple diffusion but water is special (polar but its small enough to get through)

- water following [] gradient through a semi-permeable membrane

- passive transport

Hypertonic

- more solute in the ENVIORNMENT than in the cell

- more water in the cell than in the environment

Hypotonic

- less solute in the ENVIORNMENT than in the cell

- more water in the environment than inside the cell

Isotonic

- Equal amounts of water and solute in the cell and in the environment

Lysis

- Occurs under a HYPOTONIC environment in an ANIMAL CELL

- the water enters the cell as there is less water and more solute inside the cell

- cell bursts from the high amount of water, spilling out contents

Crenation

- Occurs under a HYPERTONIC environment in an ANIMAL CELL

- There is more water and less solute inside the cell and less water and more solute in the environment so the water leaves the cell in large amounts

- The cell shrivels and eventually dies

Turgor Pressure

- Occurs in a HYPOTONIC environment in a PLANT CELL

- The cell fills with water and expands, pushing on the cell wall

- Cell wall does not budge, but the water creates pressure

- Plant is rigid

Plasmolysis

- Occurs in a HYPERTONIC environment in a PLANT CELL

- The water leaves the cell, causing the cell to shrivel and become smaller than the cell wall

- Plant is floppy

Molecular Active Transport

- the transport of solute against its concentration gradient

- transports one molecule

- needs ATP

What are the two types of Molecular Active Transport?

- Primary

- Secondary

Primary Active Transport

- Molecular

- Direct use of ATP

- Molecule moves against [] gradient

- Uses carrier protein as an ION PUMP

- Creates a new concentration []

How does an ion pump created by Primary Active Transport function?

- ATP alters attaches and alters shape to face other side and release one molecule, a different molecule attaches to the carrier, ATP is removed and the carrier shape faces original side, releases the new molecule on that side

Secondary Active Transport

- Indirect use of ATP, uses the energy stored in the charge of electrochemical gradient created by the ion pump (ions pile in one spot, creating charge)

Bulk Active Transport

- moves a bunch of molecules in and out of the cell using vesicles

What are the different kinds of Bulk Active Transport called?

- endocytosis

- exocytosis

Endocytosis

- Bulk Active Transport

- Moves a large amount of molecules into the cell using a vesicle

Exocytosis

- Bulk Active Transport

- Moves a large amount of molecules out of the cell using a vesicle

What are the three types of endocytosis?

- Pinocytosis

- Phagocytosis

- Receptor-mediated cytosis

Pinocytosis

- Type of endocytosis

- engulfs a liquid and the small particles dissolved or suspended in it into a vesicle to be moved in the cell

Phagocytosis

- Type of endocytosis

- engulfs a large molecule along with some of the liquid around it into a vesicle to be moved in the cell

Receptor-mediated cytosis

- Type of endocytosis

- Receptor proteins in the cell membrane bind to specific molecules and engulf them into a vesicle coated with the protein