EXAM 3 CH 5&6

nucleic acid

molecule that stores genetic information

carbohydrate

molecule made of sugars that provides energy and structural support

macromolecules

large complex molecules essential for life, including proteins, nucleic acids, carbohydrates, and lipids.

polymer

a long molecule consisting of building blocks connected by covalent bonds

monomer

the basic building block of polymers

enzyme

a type of protein that acts as a catalyst to accelerate chemical reactions in biological systems.

dehydration reaction

condensation reaction that involves the loss of a water molecule when two molecules are joined together.

hydrolysis

a chemical process that breaks down a compound by adding water

Monosaccharides

simple sugar carbohydrates

Disaccharide

a carbohydrate composed of two monosaccharides

Polysaccharide

a carbohydrate composed of multiple monosaccharides linked together.

glycosidic linkage

a covalent bond formed between two monosaccharides

glycogen

a polysaccharide stored by animals

cellulose

a polysaccharide that provides structural support in the cell walls of plants.

saturated fat

a type of fat that is fully hydrogenated, containing no double bonds between carbon atoms, typically solid at room temperature and are found in animal products.

Unsaturated fat

a type of fat that contains one or more double bonds between carbon atoms, typically liquid at room temperature and found in plant oils.

fatty acid

fat with long carbon skeleton that can be saturated or unsaturated

Phospholipid

fat molecule that has two fatty acid tails and a phosphate group

Steroid

a type of lipid characterized by a carbon skeleton with four fused rings

Cholesterol

a type of steroid that is a component of cell membranes and serves as a precursor for other steroids.

protein

a biologically functional molecule made of one or more polypeptides

catalyst

a substance that increases the rate of a chemical reaction without being consumed in the process.

polypeptide

a chain of amino acids linked by peptide bonds, which folds into a functional protein.

amino acid

organic molecule with a carboxyl group, an amino group, and a side chain (R group), serving as the building blocks of proteins.

peptide bond

a covalent bond formed between the carboxyl group of one amino acid and the amino group of another, releasing a molecule of water.

primary structure

the specific sequence of amino acids in a polypeptide chain.

secondary structure

the coils and folds that arise from hydrogen bonding between the atoms of the polypeptide backbone.

a helix

a coil held together by hydrogen bonds between every fourth amino acid

b pleated sheet

two or more segments of the polypeptide chain lying side by side, connected by hydrogen bonds.

tertiary structure

the overall three-dimensional shape of a polypeptide, determined by interactions among various side chains (R groups) and the main chain.

hydrophobic interaction

a nonpolar side chain attraction that stabilizes protein structure in aqueous environments.

quaternary structure

overall protein that results from the aggregation of multiple polypeptide chains

sickle-cell disease

a genetic disorder caused by a mutation in the hemoglobin gene, leading to abnormal red blood cell shapes and associated complications.

denaturation

the process by which a protein loses its native structure due to environmental factors, resulting in loss of function.

x-ray crystallography

most common method of finding a proteins three-dimensional structure

nucleic acid

molecules that store and transmit genetic information

DNA

a type of nucleic acid that carries genetic information in living organisms and is composed of two strands forming a double helix.

RNA

a nucleic acid involved in protein synthesis and gene expression.

gene expression

DNA - RNA - protein

polynucleotide

a polymer consisting of many nucleotide monomers linked in a chain

nucleotide

the basic building block of nucleic acids, made up of a sugar, phosphate group, and nitrogenous base.

nucleoside

nucleotide without a phosphate group

pyrimide

a nitrogenous base with a single-ring structure, such as cytosine, thymine, or uracil.

purines

Nitrogenous base with a 6-membered ring fused to a 5-ring

deoxyribose

The sugar component of DNA, lacking one oxygen atom compared to ribose

double helix

A structure formed by two strands of nucleotides coiling around each other

antiparallel

two sugar-phosphate back bones running opposite of each other

tRNA

type of RNA that brings amino acids to the ribosome during protein synthesis

genome

the complete set of genetic material in an organism

Bioinformatics

the application of computer technology to the management and analysis of biological data

light microscope (LM)

A type of microscope that uses visible light and a system of lenses to magnify images of small samples

magnification

the ratio of an object’s image size to its real size

resolution

a measure of the clarity of the image

contrast

the difference in brightness between the light and dark areas of an image

organelles

the membrane enclosed structures within eukaryotic cells

electron microscope (EM)

a type of microscope that uses a beam of electrons to create an image of the specimen, achieving higher resolution than light microscopes.

scanning electron microscope (SEM)

A type of electron microscope that provides three-dimensional images of the surface of a specimen by scanning it with a focused beam of electrons.

transmission electron microscope (TEM)

A type of electron microscope that transmits electrons through a specimen to create highly detailed two-dimensional images, often used to observe internal structures.

biochemistry

the study of chemical processes of cells

cell fractionation

a process that takes cells apart and separates major organelles

centrifuge

A device used to separate components of a mixture based on density by spinning them at high speed.

plasma membrane

the selective barrier of a cell

cytosol

jelly like substance inside cells

chromosomes

structures made of DNA that contain genetic information.

ribosomes

small complexes that make protiens according to gene instructions

nucleoid

region in prokaryotic cells containing genetic material without a membrane.

microvilli

finger-like projections on the surface of cells that increase surface area for absorption.

nuclear envelope

a structure that encloses the nucleus and separates its contents from the cytoplasm

pore complex

a protein structure in the nuclear envelope that regulates the passage of molecules in and out of the nucleus.

nuclear lamina

a network of intermediate filaments that provides structural support and mechanical stability to the nuclear envelope.

nuclear matrix

a fibrous network within the nucleus that organizes nuclear contents and plays a role in gene expression and DNA replication.

chromatin

the complex of DNA and proteins found within the nucleus, which condenses to form chromosomes during cell division.

free ribosomes

ribosomes suspended in the cytosol that synthesize proteins for use within the cell.

bound ribosomes

ribosomes attached to the endoplasmic reticulum that synthesize proteins for secretion or for use in membrane-bound organelles.

endomembrane system

A network of membranes involved in the synthesis, modification, packaging, and transport of proteins and lipids in eukaryotic cells.

vesicles

small membrane-bound sacs that transport materials within the cell and between different compartments of the endomembrane system.

endoplasmic reticulum (ER)

A network of membranes that synthesize lipids, metabolize carbs, detox, and store calcium

glycoproteins

proteins with carbohydrates covalently bonded to them

Golgi apparatus

warehouse for shipping, receiving, sorting, and manufacturing proteins

transport vesicles

Small membrane-bound sacs that move proteins and other substances between cellular compartments, including from the endoplasmic reticulum to the Golgi apparatus.

lysosome

An organelle containing digestive enzymes that break down waste materials and cellular debris.

phagocytosis

The process by which a cell engulfs solid particles or other cells

vacuoles

large vesicles that store nutrients, waste products, or other substances.

mitochondria

organelle that is the cite of cellular respiration and energy production in the form of ATP.

chloroplasts

organelles that conduct photosynthesis

endosymbiont theory

theory that states mitochondria and chloroplasts originated as independent prokaryotic organisms that were engulfed by a host cell.

cristae

folds of the inner membrane of mitochondria that increase surface area for ATP production.

mitochondrial matrix

The space within the inner membrane of mitochondria, containing enzymes for the citric acid cycle and mitochondrial DNA.

chlorophyll

A green pigment found in plants that is essential for photosynthesis

thylakoids

interconnected sacs within chloroplasts that contain chlorophyll and are the site of the light-dependent reactions of photosynthesis.

granum

a stack of thylakoids in chloroplasts

stroma

the fluid-filled space surrounding the thylakoids in chloroplasts

plastids

organelles in plant cells responsible for the synthesis and storage of food.

peroxisome

a metabolic compartment that remove hydrogen atoms and transfer them to oxygen

glyoxysomes

a type of peroxisome found in plants that converts stored fats into sugars

cell motility

refers to the ability of cells to move and change their position

motor proteins

proteins that use “feet” to “walk” to their destinations

microtubules

hallow rods made from tubulin that provide structural support and facilitate intracellular transport.

centrosome

a cellular structure that serves as the main organizing center for microtubules

centrioles

composed of nine sets of triplet microtubules arranged in a ring