What makes a substance an element and give example.
When a substance can't be brokendown into different parts
ex. gold, iron, mercury, carbon,helium
What is an atomic number?
What is an atom and what is it composed of?
- smallest units that have all the chemical properties of the element
- composed of electrons, protons, and nuetrons
What is an isotope?
Forms of an element with different numbers of neutrons
they are unstable and decay
Capabilites of rings of electrons
- First ring is only capable of holding 2 electrons
- Second ring holds up to 8 electrons
Most often the number of protons ______ the number of neutrons.
What is a half life?
- the amount of time for 50% of isotope to decay
- C14 half life=5730 years
What is an ion?
forms of an element with different numbers of electrons
What is a molecule?
two or more atoms linked together
What is a chemical bond and what are the 3 kinds?
attractive forces between atoms
3 types- covalent, ionic, hydrogen
What is a covalent bond?
- physically sharing electron
- shared pair of electrons
What is an Ionic bond?
- 2 ions (one positive, one negative) are attracted to each other
- Sodium ion gives an electron to Chloride and becomes +1 and Chlorine is -1 and attract to each other
What is a Hyrdogen bond?
- Hyrdogen usually loses electron and becomes positive
- they positive and negative ends attract
Properties of Water and why does ice float?
- sticky, clingy, has surface tension, takes lots of energy to heat water
- ice floats because the molecules have spaces in between them and leaves trapped spaces and makes it lighter than liquid water
What does a solvent do and give example.
- A solvent dissolves other molecule
- Water is a solvent
What is a free radical?
a single floating proton (charge of +1) with no electron
What happens when there is a single electron in an electron ring?
- it is usually plucked of
- sodium becomes sodium hydroxide
What does Hydrophilic mean and examples?
- water loving
- ex. sugar, salt
What does hydrophobic mean and examples?
- water fearing
- ex. olive oil, baking grease, care grease, lipids, fats
How do geckos cling to surfaces?
they form hydrogen bond on their hands and feet with the objects they walk on
What 4 biological molecules do all living things contain?
carbohydrates, proteins, lipids, nucleic acids
What are Carbohydrates?
- sugars and starches
- potatoes corns
- simple sugars are the bases for carbohydrates
protein forms and roles
- beans, soy, meat, animals, nuts
- structure, cell f(x), messengers, transport, communication
what are polypeptides?
- amino acid chains
- there are 20 kinds
lipids forms and roles
- animals, lard, olive oil, sesame oil, coconut oil
- energy storage, steroids, membranes
lipids and cells
create a double membrane around cells
roles of nucleic acid
- carry the "code" of life
- DNA and RNA (they are made up of chains of nucleotides)
Why are carbohydrates important?
for cell recognition, energy storage, and cell structure
Examples of monosaccharides.
- glucose, fructose
- glucose=what cells break down for energy
Example of dissacharides.
- sucrose (table sugar)
- they are 2 simple sugars linked
- formed by a condensation reaction and gives off water
What is ATP?
useable energy source that fuels cells
DNA and RNA are each made up of only __ nucleotides.
flexible and "fluid", protective covering around cell, studded with proteins
- membrane can allos some molecules to pass, others to be kept out
- size, concentration, and solubilty determine how molecules pass through a membrane
What is facilitated diffusion?
pass through a protein "gate or channel" in the membrane
What is active transport?
uses energy to move molecule across a membrane (can work against a concentration gradient)
they are cells that are able to take in really large molecules, bacteria, viruses, cell debris, and large proteins
the process of bringing into the cell is ___ and taking out
contains DNA in a nuclear envelope, proteins in envelope allow materials to pass in and out of nucleus, DNA code is converted to RNA code, RNA leaves nucleus
- in the cytoplasm “read” the RNA and make
Endoplasmic Reticulum (ER)
- makes and modifies proteins, called “rough” due to
- ribsomes sticking out of
- the membranes
further modifies proteins, ships proteins around cell and outside cell, like FedEx of cell
lipid production cholesterol, sex hormones, Vitamin D synthesis
"packets" of digestive enzymes, break down and recylce cell components, foreign materials
protein fibers within cell give structure and support
energy production, breakdown sugars (glucose) and produce ATP, have their own DNA and ribosomes, it is ONLY inherited through egg (maternally, you can trace it back for lineage), is like MLGW provides energy
use solar energy to synthesize sugars, cholorphyll-pigment gives plants green color
fluid-filled sacs, give cells "firmness"
give cells structure, "cells" that Hooke saw, wood, cellulose (undigestable to us)
How HIV takes over a cell
- 1- needs to insert genetic material
- 2- convert RNA into DNA
- 3- get cell to make copies of DNA and to convert it to RNA
- 4 - have cell make proteins from the RNA
- 5 - Assemble proteins and new viruses
- 6 - leave cell to infect new cells