Principles and Concepts

homeostasis

"ready state" the ability of an organism to maintain constant internal conditions.

adenosine triphosphate

(ATP), the cell's main energy-carrying molecule.

smooth endoplasmic reticulum

(SER) is continuous with the RER but has few or no ribosomes on its cytoplasmic surface.

eukaryotic

A cell characterized by the presence of a nucleus and other membrane-bound organelles. Can be unicellular (protists) or multicellular (fungi, plants and animals).

thylakoids

A flattened membrane sac inside the chloroplast, used to convert light energy to chemical energy.

hemoglobin

A four-subunit protein found in red blood cells that binds oxygen. Each subunit contains a heme group, a large multi-ring molecule with an iron atom at its center. One molecule can bind four oxygen molecules in a cooperative manner.

chlorophyll

A green photosynthetic pigment found in the chloroplasts of plants, algae, and some bacteria.

genus

A group of similar species

flagella

A long, whip-like filament that helps in cell motility.

osmolarity

A measure of the total solute concentration per liter of solution

phospholipid

A molecule that is a constituent of the inner bilayer of biological membranes, having a polar, hydrophilic head and a nonpolar, hydrophobic tail.

conjugation

A primitive form of sexual reproduction that is characteristic of bacteria and some algae

peptidoglycan

A protein-carbohydrate compound that makes the cell walls of bacteria rigid

lysosomes

A small, round cell structure containing chemicals that break down large food particles into smaller ones.

nucleolus

A specialized structure in the nucleus, formed from various chromosomes and active in the synthesis of ribosomes

granum

A stack of thylakoids in a chloroplast

Chloroplasts

A structure in the cells of plants and some other organisms that captures energy from sunlight and uses it to produce food.

cellulose

A substance (made of sugars) that is common in the cell walls of many organisms

solute

A substance that is dissolved in a solution.

monocytes

A type of white blood cell that transforms into macrophages, extends pseudopods, and engulfs huge numbers of microbes over a long period of time

pili

Appendages that allow bacteria to attach to each other and to transfer DNA

organ system

An anatomical system composed of a group of organs that work together to perform a specific function or task.

concentration gradient

An increase or decrease in the density of a chemical substance in an area.

collagen

An insoluble fibrous protein of vertebrates that is the chief constituent of the fibrils of connective tissue (as in skin and tendons) and of the organic substance of bones.

Golgi apparatus

An organelle in eukaryotic cells consisting of stacks of flat membranous sacs that modify, store, and route products of the endoplasmic reticulum.

heterotrophs

An organism that obtains organic food molecules by eating other organisms or their by-products.

prokaryotic

An organism whose cells do not have an enclosed nucleus or other membrane-bound organelles, such as bacteria. uni cellular organisms.

red blood cells

Blood cells that carry oxygen from the lungs to the body cells.

white blood cells

Blood cells that perform the function of destroying disease-causing microorganisms

lyse

Cell bursting.

isotonic

Describes a solution whose solute concentration is equal to the solute concentration inside a cell

Protist

Eukaryotic organisms that did not fit the criteria for the kingdoms Animalia, Fungi, or Plantae historically were called protists and were classified into the kingdom Protista

microvilli

Fingerlike extensions of plasma membrane of apical epithelial cells, increase surface area, aid in absorbtion, exist on every moist epithelia, but most dense in small intestine and kidney

fimbriae

Fingerlike projection of the uterin (fallopian) tubes that drape over the ovary.

turgor pressure

Force exerted on a plant cell wall when water enters the cell by osmosis; keeps plant from wilting.

hydrophobic

Having an aversion to water; tending to coalesce and form droplets in water.

hypotonic

In comparing two solutions, referring to the one with a lower solute concentration.

cristae

Infoldings of the inner membrane of a mitochondrion that houses the electon transport chain and the enzyme catalyzing the synthesis of ATP.

glycoproteins

Membrane carbohydrates that are covalently bonded to proteins.

diffusion

Movement of molecules from an area of higher concentration to an area of lower concentration.

macrophages

On what type of immune cell is each of the following cell surface proteins found

micrographs

Photographs taken with microscopes.

ecologists

Scientists who study relationships between organisms and environments.

receptors

Special structures that allow living organisms to sense the conditions of their internal or external environment

fluid mosaic model

Structural model of the plasma membrane where molecules are free to move sideways within a lipid bilayer.

chromatin

Substance found in eukaryotic chromosomes that consists of DNA tightly coiled around histones

cells

The basic unit of structure and function in all living things

stroma

The fluid of the chloroplast surrounding the thylakoid membrane; involved in the synthesis of organic molecules from carbon dioxide and water.

hypertonic

When comparing two solutions, the solution with the greater concentration of solutes

T-helper cells

The middle-man or main "helper" of the immune response . These cells receive info from non-specific phagocytic cells and pass that info on to generate a specific response to a particular antigen. These are also called CD4 T-cells, dues to the presense of the CD4 marker.

cellular respiration

The process by which cells use oxygen to produce energy from food

botany

The study of plants

extracellular matrix

The substance in which animal tissue cells are embedded, consisting of protein and polysaccharides.

Bacteria

another quite different group of single-celled organisms without nuclei

tissue factor

Triggers the extrinsic pathway of blood clotting

selectively permeable

a property of cell membranes that allows some substances to pass through, while others cannot

phagocytosis

a section of the plasma membrane of the macrophage invaginates (folds in) and engulfs a pathogen.

Fit

adaptation and it is a consequence of evolution by natural selection which operates in every lineage of reproducing organisms.

plasma membrane

an outer covering that separates the cell's interior from its surrounding environment

Paleontology

another branch of biology, uses fossils to study life's history

Integral proteins

are embedded in the plasma membrane and may span all or part of the membrane.

Peripheral proteins

are found on the exterior or interior surfaces of membranes, attached either to integral proteins or to phospholipid molecules

organisms

are highly organized structures that consist of one or more cell. Single sells are complex. Inside each cell atoms make up molecules. These then turn to make up components or organelles.

vacuoles

are membrane-bound sacs that function in storage and transport.

Mitochondria

are often called the "powerhouses" or "energy factories" of a cell because they are responsible for making adenosine triphosphate

Peroxisomes

are small, round organelles enclosed by single membranes.

Carbohydrates

are the third major component of plasma membranes. They are always found on the exterior surface of cells and are bound either to proteins (forming glycoproteins) or to lipids (forming glycolipids).

organs

collections of tissue grouped together based on common function.

cytoplasm

consisting of a jelly-like region within the cell in which other cellular components are found

Archaea

e single-celled organisms without nuclei and include many extremophiles that live in harsh environments like hot springs.

facilitated transport

material moves across the plasma membrane with the assistance of transmembrane proteins down a concentration gradient (from high to low concentration) without the expenditure of cellular energy.

hydrophilic

having a tendency to mix with, dissolve in, or be wetted by water.

endomembrane system

is a group of membranes and organelles in eukaryotic cells that work together to modify, package, and transport lipids and proteins

Passive transport

is a naturally occurring phenomenon and does not require the cell to expend energy to accomplish the movement.

centrosome

is a region near the nucleus of animal cells that functions as a microtubuleorganizing center

Symbiosis

is a relationship in which organisms from two separate species live in close association and typically exhibit specific adaptations to each other

cell wall

is a rigid covering that protects the cell, provides structural support, and gives shape to the cell.

endoplasmic reticulum

is a series of interconnected membranous tubules that collectively modify proteins and synthesize lipids

rough endoplasmic reticulum

is so named because the ribosomes attached to its cytoplasmic surface give it a studded appearance when viewed through an electron microscope.

Osmosis

is the diffusion of water through a semipermeable membrane according to the concentration gradient of water across the membrane.

Microbiology

is the study of the structure and function of microorganisms

macro molecules

larger molecules formed by combining smaller units called monomers cells containing aggregates of ----- -----surrounded by membranes.

multi cellular organisms

organism made up of many cells

Eukarya

organisms that have cells with nuclei

ribosomes

particles that synthesize proteins. However, prokaryotes differ from eukaryotic cells in several ways.

Endosymbiosis

process responsible for the evolution of mitochondria and chloroplasts in eukaryotes.

transport proteins

protein molecules that help to transport substances throughout the body and across cell membranes

antigens

proteins associated with invasive pathogens

biotechnologists

research cell's, DNA, and living systems to discover new medical treatment

physiologists

scientists who study the physical workings of the body and its systems

vesicles

small membrane sacs that specialize in moving products into, out of, and within a cell

lumen

space within a tubular part or organ, such as the space within a blood vessel

cytotechnologist

specialized technician that tests cells

pathologist

specializes in the laboratory analysis of tissue samples to confirm or establish a diagnosis

molecular biology

studies biological processes at the molecular level, including interactions among molecules such as DNA, RNA, and proteins, as well as the way they are regulated

neurobiology

studies the biology of the nervous system, and although it is considered a branch of biology, it is also recognized as an interdisciplinary field of study known as neuroscience.

Zoology

the branch of biology that deals with animals

binomial naming system

the system used for naming organisms.

thermoregulation

the ways in which organisms regulate their internal heat

centrioles

two structures that lie perpendicular to each other. Each is a cylinder of nine triplets of microtubules.