Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology 120 Midterm > Biomolecules II > Flashcards

Biomolecules II Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

Glycogen

A
  • When fungi and animals absorb/ingest more α-glucose than they can use, they store some of the excess in the form of glycogen
  • A polymer formed of α-glucose monomers linked through α1-4 glycosidic bonds
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Cellulose

A
  • When plants need structural support, they produce β-glucose through photosynthesis and link them together to form cellulose
  • A polymer formed of β-glucose monomers linked through β1-4 glycosidic bonds
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Chitin

A
  • Fungi use β-glucose monomers and link them together to form the polymer chitin
  • A chitin polymer is formed of β-glucose monomers linked through β1-4 glycosidic bonds
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Neutral Fats

A
  • Major type of lipid
  • Fats used for energy storage, insulation, and protecting your internal organs
  • Constructed from two types of molecules: Fatty acid and Glycerol
  • Fatty acid molecules can be linked to a glycerol molecule through a condensation reaction to form an ester bond
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Phospholipids

A
  • Function: Major constituents of cell membranes, also forms lipoproteins
  • Structure: 2 fatty acid molecules, 1 glycerol molecule, 1 phosphate molecule
  • Phospholipids are amphipathic as they contain both hydrophilic and hydrophobic groups in the same molecule (hydrophilic head, hydrophobic tail)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Steroids

A
  • Function: Constituents of cell membranes (cholesterol), components of vitamins, components of hormones
  • Structure: Made from sterol – four fused rings composed of 20 bonded carbon atoms bonded
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Fatty Acid

A
  • One type of molecule used to construct a neutral fat
  • Fatty acids are found in nature in either a saturated or unsaturated state
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Glycerol

A
  • The other type of molecule used to construct a neutral fat
  • A single glycerol molecule can hold either 1, 2 or 3 fatty acids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Ester Bond

A
  • When fatty acid molecules are linked to a glycerol molecule through a condensation reaction, an ester bond is formed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Saturated Fatty Acid

A
  • “Classical” one
  • All carbon atoms in the hydrocarbon chain are connected to each other by single covalent bonds
  • Known as “saturated” because every single carbon has a maximum number of hydrogens attached to it
  • Solid at room temperature (butter)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Unsaturated Fatty Acid

A
  • Most carbon atoms in the hydrocarbon chain are linked by single bonds, but some carbon atoms are linked by double bonds
  • Missing some hydrogen atoms, therefore not “saturated” with hydrogen
  • Liquid at room temperature (vegetable oil)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Lipoproteins

A
  • Hydrophobic fats must be circulated through the blood by way of specialized transport proteins called lipoproteins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

High Density Lipoproteins (HDL)

A
  • HDL particles remove fats and cholesterol from cells and from the circulatory system and transport it back to the liver for excretion or re-utilization
  • AKA good cholesterol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Low Density Lipoproteins (LDL)

A
  • Carry cholesterol from the liver to cells of the body
  • LDL particles can also transport fat molecules into the artery wall, and start the formation of plaques
  • AKA bad cholesterol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Membrane

A
  • Incredibly versatile and critical structures to the function of the cell
  • Found both inside the cell (in eukaryotes) and surrounding the entire cell (in both prokaryotes and eukaryotes)
  • Act as the gatekeepers controlling what enters or leaves the cell
  • Are how the cell senses and responds to its environment (responds to external stimuli)
  • Protects themselves and maintain their internal environment (homeostasis)
  • Generate electrochemical gradients that allow them to convert chemical or light energy to biological energy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What biomolecules are important in cell membranes and why?

A
  • Lipids: main structure and adjacent compounds
  • Proteins: transport, electrochemical gradient, signaling
  • Carbohydrates (cell to cell recognition)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Bilayer

A
  • Phospholipids are organized into a lipid bilayer
  • Hydrophilic heads on the outside
  • Hydrophobic tails contained within the membrane
  • Within the lipid bilayer, the phospholipids are mobile (turn on their axis, move laterally in any direction over the surface of the membrane, flipping across membrane is rare)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How are cell membranes fluid?

A
  1. The type of fatty acid chains in the phospholipid
    - Increasing the number of saturated fatty acids will decrease membrane fluidity
    - Increasing the number of unsaturated fatty acids will increase membrane fluidity
  2. The presence of cholesterol
    - Cholesterol is amphipathic, with both hydrophobic and hydrophilic parts
    - The hydrophilic group binds to the phospholipid head and the hydrophobic tail binds to the hydrophobic tail of the adjacent phospholipid
    - Helps maintain the integrity of membranes by preventing membranes from becoming either too fluid or too rigid
19
Q

Fluid Mosaic Model

A
  • Current understanding of membrane structure is referred to as the fluid mosaic model
  • Emphasizes the movement of phospholipids in the membrane
20
Q

Cell Membrane Carbohydrates

A
  • Membrane bound carbohydrates are involved in cell-to-cell recognition
  • Types of membrane carbohydrates are differentiated based on what they are attached to in the membrane
  • Glycolipids and glycoproteins
  • Membrane carbohydrates are shaped to bind to specific compounds (like a lock and key)
20
Q

Glycolipids

A
  • Lipid with carbohydrate attached
  • Carbohydrates covalently bonded to lipids
21
Q

Glycoproteins

A
  • Protein with carbohydrate attached
  • Carbohydrates covalently bonded to proteins
22
Q

Cell Membrane Proteins

A
  • Proteins associate with membranes in one of two ways: peripheral membrane proteins and integral membrane proteins
  • Proteins in cell membranes act as transporters, receptors, enzymes, and anchors
23
Q

Peripheral Membrane Proteins

A
  • Temporarily associated with integral membrane proteins through hydrogen bonds
  • Easily separated from the membrane
  • Play a role in transmitting information received from external signals
24
Q

Integral Membrane Proteins

A
  • These proteins cross the membrane, lead from extracellular space to intracellular space
  • Composed of three regions: 2 hydrophilic regions and 1 hydrophobic region
  • Hydrophobic region is embedded in the membrane
  • Hydrophilic regions extend outside the membrane
25
Q

Receptor Proteins

A
  • Accept (binds) a signal outside the membrane
  • Causes a change in protein shape by alerting the cell of the reception of the signal
26
Q

Enzyme Proteins

A
  • Membrane proteins which facilitate a chemical reaction
27
Q

Anchor Proteins

A
  • Anchor lipids found outside (extracellular) or inside (intracellular) the cell
28
Q

Transport Proteins

A
  • Regulate movement of ions and small molecules across the membrane
  • This is the most complex and important function of the membrane
29
Q

Passive Transport

A
  • Form of movement across the membrane
  • No energy is invested in order to move molecules across the cell membrane
  • Takes advantage of diffusion and osmosis
30
Q

Active Transport

A
  • Form of movement across the membrane
  • Energy must be invested in order to move molecules across the cell membrane
  • Cannot take advantage of diffusion or osmosis
  • Moves solutes against a concentration or electrochemical gradient
31
Q

Diffusion

A
  • Form of movement across the membrane
  • Energy must be invested in order to move molecules across the cell membrane
  • Cannot take advantage of diffusion or osmosis
  • Moves solutes against a concentration or electrochemical gradient
32
Q

Osmosis

A
  • Water in cells contains dissolved solutes
  • When water has dissolved solutes and a semi-permeable membrane, it results in osmosis
33
Q

Facilitated Transport

A
  • Method of passive transport
  • Many polar or large molecules cannot pass freely through the plasma membrane (ex: water, proteins, sugars, ions)
  • They require membrane bound proteins to open a path through the hydrophobic region of the lipid bilayer
  • Compounds are transported across the membrane through integral membrane proteins
  • Two types of proteins involved: channel proteins and carrier-mediated proteins
34
Q

Concentration Gradients

A
  • Passive transport generally depends on concentration gradients
  • Items move across in the membrane from an area of higher concertation to lower concentration
35
Q

Electrochemical Gradient

A
  • The spaces on either side of a membrane in the cell usually have different net charges
  • One side will be more positive than the other
  • The differences in charges is called an electrochemical gradient
  • Electrochemical gradients influence the movement of ions and charged molecules during passive transport (move from region of high charge to low charge)
36
Q

Channel Proteins

A
  • Molecules (mainly ions) move down their concentration gradient or electrochemical gradient)
  • Proteins can exclude the passage of molecules based on size (too large) or charge
  • However, any molecule that fits the size and charge requirements flows freely through
37
Q

Carrier Proteins

A
  • Much more specific than channel proteins
  • Contains a specific binding site (lock and key) for a specific compound
  • Binding that compound causes a change in protein shape
  • The change in shape moves the chemical to the other side of the membrane
38
Q

Semi-Permeable

A
  • Allowing certain substances to pass through it but not others, especially allowing the passage of a solvent but not of certain solutes
39
Q

Aquaporins

A
  • Water molecules cross the cell membrane through special channel proteins called “aquaporins”
  • Water molecules move from an area of low solute concentration to high solute concentration
  • Aquaporins ONLY allow for the passage of water molecules
  • The presence of aquaporins in a membrane creates a semi-permeable membrane for water transport
40
Q

Primary Active Transport

A
  • Directly spends energy to move solutes across the membrane (energy source: ATP)
  • Uses integral membrane proteins
  • Generally binds compounds for transport (similar to carrier proteins of passive transport)
  • Reinforces existing electrochemical gradients across the plasma membrane
  • Results in stored potential energy across the membrane (this energy is then used in secondary active transport)
41
Q

Secondary Active Transport

A
  • Uses a pre-existing electrochemical gradient (ATP or other energy molecules = not involved)
  • Defined by the cotransport of two different solutes through the same transport protein (one solute is moving with its concentration gradient, one solute is moving against its concentration gradient)
42
Q

3 Domains of Life

A

Bacteria, Archaea, Eukarya

Biology 120 Midterm (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions