Untitled Flashcard Set

Cell

The smallest unit that can live on its own and that makes up all living organisms and the tissues of the body.

Organelle

A small structure in a cell that is surrounded by a membrane and has a specific function.

Macromolecule

Very large molecules made of many smaller parts joined together.

Nucleotide

The base building block of nucleic acids like DNA & RNA, consisting of a 5-carbon sugar, phosphate group, and a nitrogen-containing base.

Fatty acid

The building blocks of the fat in our bodies and in the food we eat.

Monosaccharide

The simplest form of carbohydrates or single sugar molecules.

Amino acid

Small organic molecules that link together to build proteins.

Enzyme

Special proteins made by living cells that act as biological catalysts to speed up chemical reactions without being used up.

Catalyst

A substance that speeds up a chemical reaction without being changed itself.

Active site

A small specific pocket or cleft on the surface of an enzyme or protein.

Differentiation

The process where a basic, unspecialized cell changes into a specific mature cell type with a unique job.

Characteristics of living things

1. Made of cells; 2. Respond to stimuli; 3. Able to grow and reproduce; 4. Use energy; 5. Contain genetic material.

Cytoplasm

The jelly-like fluid inside the cell that holds everything in place.

Cell (Plasma) Membrane

A permeable barrier that controls what goes in and out of the cell to maintain homeostasis.

Cytoskeleton

Network of threadlike protein fibers that support the cell and help with motility and biochemical activities.

Centrioles

Made of microtubules, appear during cell division to help pull chromosomes apart.

Cilia

Short, numerous projections that move fluid across the cell’s surface.

Flagella

Longer, fewer projections that move the entire cell through extracellular fluid.

Nucleus

Contains genetic material; surrounded by a nuclear envelope with pores to control substance movement.

Ribosomes

The site of protein synthesis, made of rRNA and proteins.

Rough ER

Network of sacs with ribosomes that makes and packages proteins for export.

Smooth ER

Network of sacs with no ribosomes that makes lipids and modifies small molecules.

Lysosomes

Contain enzymes to break down food, bacteria, and old cell parts.

Vacuoles

Storage sacs for water, nutrients, and waste in cells.

Mitochondria

Site of cellular respiration, breaking down food into usable energy in the form of ATP.

Phospholipid Bilayer

The structure of the cell membrane; a hydrophilic head and hydrophobic tail that controls substance movement.

Transport Control: Passes Easily

Small nonpolar molecules and water can easily pass through the cell membrane.

Transport Control: Cannot Pass Easily

Polar molecules and large molecules require protein channels or vesicles to cross the cell membrane.

Macromolecule: Nucleic Acids

Composed of nucleotides; they store and express genetic information.

Macromolecule: Lipids

Composed of fatty acids and glycerol; used for energy storage and structural purposes.

Macromolecule: Carbohydrates

Composed of monosaccharides; used for energy storage and transport.

Macromolecule: Proteins

Composed of amino acids; serve various functions including enzyme activity and transport.

DNA

Organizes into chromosomes and genes, providing instructions for protein creation.

Chromosomes

Coiled structures of DNA holding genes.

Genes

Sections of chromosomes that get transcribed into mRNA, later translated into proteins.

Protein Synthesis Step 1

DNA unzips to create a single-stranded copy of mRNA.

Protein Synthesis Step 2

tRNA transfers corresponding amino acids to ribosomes, bonding them into polypeptide chains.

Role of Enzymes

Act as biological catalysts to speed up reactions by lowering activation energy.

Enzyme Specificity

Enzymes only bind to matching substrates at their active sites; specificity is key.

Environmental changes effect on enzymes

Altering pH or temperature can change the shape of the active site, affecting enzyme function.

Levels of Organization

Organism > Organ System > Organ > Tissue > Cell

Cell Cycle: Interphase

Cell spends most of its life here; DNA doubles preparing for division.

Cell Cycle: Mitosis

The division of genetic material across Prophase, Metaphase, Anaphase, and Telophase.

Cell Cycle: Cytokinesis

The splitting of cytoplasm to form two identical daughter cells.

Importance of Chromosome Duplication

Ensures daughter cells are identical to parent cells barring mutations.

Form Dictates Function

How a cell's structure determines its specific job; critical for understanding biology.

Homeostasis

The maintenance of stable internal conditions in living organisms.

Biological Catalyst

A substance that increases the rate of a chemical reaction; often refers to enzymes.

Hydrophobic

Water-repelling; refers to the tails of phospholipids in the cell membrane.

Hydrophilic

Water-attracting; refers to the heads of phospholipids in the cell membrane.

Amino Acids Role

Building blocks for proteins, linked together to form polypeptides.

Microtubules

Part of the cytoskeleton, helping to maintain cell shape and support motility.

Rough ER Function

Synthesizes proteins specifically for export out of the cell.

Smooth ER Functions

Synthesizes lipids and modifies small molecules; stores calcium.

Apoptosis

Programmed cell death, a function of lysosomes.

Homeostasis Maintenance

Regulated by the cell membrane's selective permeability.

Energy Production in Cells

Occurs in mitochondria through cellular respiration.

Nuclear Envelope

Membrane surrounding the nucleus, controlling the entry and exit of materials.

Gene Expression

The process of transcribing and translating DNA into functional proteins.

Protein Structure Levels

Includes primary, secondary, tertiary, and quaternary structures, impacting function.

Energy Storage in Lipids

Lipids are used for long-term energy storage and structural components.

Polypeptide Chains

Formed during protein synthesis, folding into functional proteins.

Nucleic Acids Functions

Store, transmit, and express genetic information.

Histone Proteins

Help package and protect DNA in chromosomes.

Cellular Metabolism

All chemical reactions that occur within a cell to maintain life.

Cell Membrane Fluidity

The ability of the phospholipids to move and reseal, allowing flexibility.

Cellular Respiration Steps

Includes glycolysis, Krebs cycle, and electron transport chain.

Endoplasmic Reticulum

An organelle involved in protein and lipid synthesis; includes both rough and smooth types.

Chloroplast

An organelle found in plants that captures sunlight for photosynthesis (not in animal cells).

Glycogen

A polysaccharide used for storage in animal cells.

Complex Carbohydrates

Polysaccharides formed from multiple monosaccharides; important for energy storage.

Signal Transduction

The process by which a cell responds to signals from hormones and other substances.

RNA Role

Mediates the translation of genetic information from DNA to protein synthesis.

Gene Regulation

Controls the timing and amount of gene expression in cells.

Cell Specialization

The process by which generic cells change into specific cells with distinct functions.