LECTURE EXAM 1 REVIEW

Monosaccharide

The simplest carbohydrate; a single sugar molecule (e.g., glucose, fructose, galactose).

What is starch?

storage polysaccharide containing mostly glucose

Functions of monosaccharides

Provide immediate energy and serve as building blocks for larger carbohydrates.

Disaccharide

A carbohydrate made of two monosaccharides joined by a glycosidic bond.

Examples of disaccharides

Sucrose, lactose, maltose.

polysaccharides

Storage (starch and glycogen) they store ENERGY - starch for plants

Structural (cellulose and chitin)

Atom

Smallest unit of matter.

Element

Substance made of one type of atom.

Compound

Two or more different elements chemically combined.

Molecule

Two or more atoms bonded together.

Isotope

Same number of protons, different number of neutrons.

pH

A measure of hydrogen ion concentration; indicates acidity or alkalinity.

Types of fats

Saturated fats: No double bonds; Unsaturated fats: One or more double bonds; Trans fats: Artificially hydrogenated fats.

Covalent bonds

Determined by valence electrons.

What pH is considered acidic?

Less than 7.

What pH is considered basic (alkaline)?

Greater than 7.

What easily crosses the cell membrane?

Small nonpolar molecules such as oxygen and carbon dioxide.

What cannot easily cross the cell membrane?

Large molecules, ions, and polar molecules.

Channel protein

A membrane protein that provides a passageway for substances.

Carrier protein

A membrane protein that changes shape to move substances across the membrane.

Diffusion

Movement of molecules from high concentration to low concentration.

Osmosis

Diffusion of water across a selectively permeable membrane.

Major organelles

Nucleus = control center; Ribosomes = protein synthesis; ER = transport/synthesis; Golgi = packaging; Lysosomes = digestion; Mitochondria = ATP production.

Microfilaments

Thin cytoskeletal fibers made of actin.

Intermediate filaments

Fibers that provide structural support.

Microtubules

Hollow tubes involved in shape, transport, cilia, and flagella.

DNA nucleotides

Made of phosphate group, deoxyribose sugar, and nitrogenous base.

Hypotonic solution

Lower solute concentration outside the cell.

What happens to animal cells in a hypotonic solution?

They swell and may burst.

Hypertonic solution

Higher solute concentration outside the cell.

What happens to plant cells in hypotonic and hypertonic solutions?

Hypotonic = turgid; Hypertonic = plasmolyzed.

Cilia and flagella movement

Using microtubules arranged in a 9+2 pattern.

Cytosol vs. cytoplasm

Cytosol = intracellular fluid; Cytoplasm = cytosol + organelles.

What dissolves in water?

Polar and ionic substances.

Why can an element form covalent bonds?

To fill its outer electron shell.

Extracellular matrix in animal cells

Made proteins and carbohydrates such as of glycoproteins, collagen fibers, and proteoglycans.

How is membrane fluidity maintained?

Cholesterol helps regulate membrane fluidity.

Active transport

Movement against the concentration gradient using ATP.

Major polysaccharides

Starch, glycogen, cellulose, chitin.

Organelle that produces ATP

Mitochondria.

Why is ice less dense than liquid water?

Hydrogen bonds create an open crystal structure.

Why is water polar?

Oxygen attracts electrons more strongly than hydrogen.

Cohesion vs. adhesion

Cohesion = water sticks to water; Adhesion = water sticks to other substances.

Mass number

Protons + neutrons.

Monomers of major polymers

Proteins → amino acids; Carbohydrates → monosaccharides; Nucleic acids → nucleotides; Lipids(not a polymer) → glycerol + fatty acids.

Starch

Plant energy-storage polysaccharide.

Glycogen

Animal energy-storage polysaccharide.

Linkage that joins monosaccharides

Glycosidic linkage.

Linkage found in lipids

Ester linkage.

Endocytosis

Cell takes material in using vesicles.

Covalent bond

Sharing of electrons.

Ionic bond

Transfer of electrons causing attraction between ions.

Hydrogen bond

Weak attraction involving hydrogen and electronegative atoms.

Difference between single, double, and triple covalent bonds

Single = 1 shared pair; Double = 2 shared pairs; Triple = 3 shared pairs.

Why do oceans become more acidic?

CO₂ dissolves in water forming carbonic acid.

Buffer

Substance that resists changes in pH.

Why is carbon the backbone of organic compounds?

Carbon forms four stable covalent bonds.

Phagocytosis vs. autophagy

Phagocytosis = engulfing external material “cell eating”

Autophagy = recycling damaged cell components.

Tay-Sachs disease

Lysosomal storage disease caused by inability to break down GM2 gangliosides.

Organelle involved in Tay-Sachs disease

Lysosome.

Major organ systems

Integumentary, skeletal, muscular, nervous, endocrine, cardiovascular, lymphatic, respiratory, digestive, urinary, reproductive.

Organelle that packages proteins

Golgi apparatus.

DNA complementary base pairs

A pairs with T; C pairs with G.

What is nucleic acid?

polymer of nucleotides or polynucleotides , genes are made of DNA

Levels of organization

Atom → Molecule → Organelle → Cell → Tissue → Organ → Organ System → Organism

Characteristics of life

Organization, metabolism, responsiveness, growth, development, reproduction, homeostasis. must have all 7! (viruses are NOT living things)

Serous membrane

Membrane lining body cavities and covering organs.

Visceral - lines the viscera

Parietal - lines the cavity

Major body cavities

Cranial, vertebral, thoracic, abdominal, pelvic.

Anatomical position

Standing upright, palms forward, feet forward.

Supine position

Lying face up.

Prone position

Lying face down.

Sagittal plane

Divides left and right.

Frontal (coronal) plane

Divides front and back.

Superior vs. inferior

Superior = above; Inferior = below.

Medial vs. lateral

Medial = toward midline; Lateral = away from midline.

Cavity that contains the lungs

Pleural cavities.

Cavity that contains the heart

Pericardial cavity.

Most common elements in living organisms

Oxygen, carbon, hydrogen, nitrogen.

Why is the membrane a phospholipid bilayer?

Hydrophilic heads face water; hydrophobic tails face inward.

Trace element

Element required in very small amounts (e.g., iron, iodine).

Organelle that contains digestive enzymes

Lysosome.

What is a polymer?

large, complex macromolecule made of repeating, smaller molecular building blocks called monomers

What is a glycosidic linkage?

A covalent bond - when two monosaccharides join to form a disaccharide

Where is cellulose found? Why can’t we break it down? EXTRA CREDIT MIDTERM 1

Found In the cell wall. Basically glucose monosaccharides linked together by glycosidic linkage, humans do not have enzyme to break it down

What does fat consist of?

What is esther linkage?

What are saturated fats?

NO DOUBLE BONDS. “Saturated” with hydrogens. Solid at room temperature, like butter! Animal fat is saturated.

What are unsaturated fats?

Have 1 or more double bonds, less hydrogen.

Proteins

Monomer is called amino acids. there are 20 kinds of amino acids, put them together to form a polypeptide chain called a peptide bond

Nucleic acids

What is phosphodiester linkage?

adjacent nucleotides joined by covalent bonds

What is messenger RNA?