cell structure (module 1)

Difference between elements and compounds

elements have one type of atom
Compounds have multiple elements

Element's number and atomic weight

Atomic number = number of protons. Atomic weight = Protons + neutrons (a little from electrons)

Electrons in energy level

2 electrons in 1st, 8 in 2nd, 8 in 3rd, 1 in 4th.

ionic bond

Formed when one or more electrons are transferred from one atom to another

covalent bond

A chemical bond that involves sharing a pair of electrons between atoms in a molecule

pH level

A measure of alkalinity or acidity. 0-7 acidic, 7-14 alkaline.

plasma membrane (cell membrane)

Regulates what enters and leaves the cell and separates the internal environment of the cell from the external environment

Nucleus

A part of the cell containing DNA and RNA and responsible for growth and reproduction

Cytoplasm

A jellylike fluid inside the cell in which the organelles are suspended

Mitochondria

Powerhouse of the cell, organelle that is the site of ATP (energy) production

active transport

Energy-requiring process that moves material across a cell membrane against a concentration difference

passive transport

Requires NO energy, Movement of molecules from high to low concentration, Moves with the concentration gradient

Diffusion

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

Osmosis

Diffusion of water through a selectively permeable membrane

isotonic solution

A solution in which the concentration of solutes is essentially equal to that of the cell which resides in the solution

hypertonic solution

A solution in which the concentration of solutes is greater than that of the cell that resides in the solution

hypotonic solution

A solution in which the concentration of solutes is less than that of the cell that resides in the solution

epithelial tissue

A body tissue that covers the surfaces of the body, inside and out

epithelial tissue functions

protection, absorption, filtration, excretion, secretion

connective tissue

A body tissue that provides support for the body and connects all of its parts

connective tissue functions

binds body tissues together, supports the body, provides protection

nervous tissue

A body tissue that carries electrical messages back and forth between the brain and every other part of the body.

nervous tissue function

Transmit electrical signals from sensory receptors and to effectors (muscles and glands) which control their activity

muscular tissue

Contracts and moves the various parts of the body.

muscular tissue function

contraction and movement

membrane

thin layer of tissue that covers a surface, lines a cavity, or divides a space or organ

epithelial membranes

cutaneous, mucous, serous

cell division (mitosis)

Process by which a cell divides into two new daughter cells

Mitosis process

part of eukaryotic cell division during which the cell nucleus divides

Glycoproteins

A protein with one or more covalently attached carbohydrates.

Glucose

the form of sugar that circulates in the blood and provides the major source of energy for body tissues. When its level is low, we feel hunger.

Glycogen

An extensively branched glucose storage polysaccharide found in the liver and muscle of animals

the animal equivalent of starch.

Microbiology

The study of microorganisms

Pathogens

disease causing agents

Types of pathogens

viruses, bacteria, parasites, fungi

Bacteria

single-celled organisms that lack a nucleus

prokaryotes

Virus

A tiny, nonliving particle that invades and then reproduces inside a living cell.