Bio Quarterly 1

plasma membrane

boundary between cell and its environment it allows things in or out of the cells and allows the cell to maintain homeostasis

selectively permeable

allows some molecules in but not others and only in certain amounts

examples of molecules that pass freely

water, glucose, O2, gas, CO2

example of molecules that are regulated

proteins, all ions (Na+, CI-), large molecules

Stucture of Plasma Membrane

composed of a phospholipid bilayer; two fatty acid tails which are non-polar and phosphate head which is polar

fluid mosaic model

model of the plasma membrane; fluid bc its flexible and mosaic bc there are so many proteins that are embedded in the membrane

choloesterol

found in the Plasma membrane to help stabilize the phospholipids and prevents them from sticking together

transport proteins

act like tunnels and assist molecules moving in and out

passive transport

diffusion through the plasma membrane that requires no energy

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; water will always move until its equal on both sides

solute

substance being dissolved

solvent

substance doing the dissolving

isotonic solution

concentration of water in the cell is equal to the water outside the cell

hypotonic solution

concentration of solute is lower outside the cell; causes cell to swell

hypertonic

concentration of solute is greater outside the cell than inside; causes cell to shrivel

facilitated diffusion

type of passive transport where substances cross the PM through a protein channel because they are polar

types of passive transport

diffusion, osmosis, facilitated diffusion

types of active transport

endocytosis, exocytosis, protein pumps, contractile vacuole

active transport

transport that requires ATP (energy)

sodium-potassium pump

A special transport protein in the plasma membrane that transports sodium out of the cell and potassium into the cell against their concentration gradients.

Endocytosis

when a cell engulfs a large molecule or even an entire cell and a portion of the PM will wrap around the molecule forming a vesicle

what are the two types of endocytosis?

phagocytosis and pinocytosis

Phagocytosis

the cell taking in solid material; cell eating

Pinocytosis

the cell taking in liquid material; cell drinking

Exocytosis

cell expelling materials such as waste, indigestible particles, and hormones

contractile vacuole

an organelle in freshwater protists that remove remove excess water from the cell

cell

smallest unit of life

what is the cell theory?

All living things are made up of cells, cells are the basic unit of living things, new cells are produced from existing cells

Unicellular

A single celled organism

Multicellular

made of many cells

Examples of unicellular organisms

bacteria, amoeba, paramecium

prokaryotic cell

type of cell bacteria are made of that have no nucleus and has a cell wall

Archeabacteria

ancient bacteria; live in extreme conditions

Eubacteria

all other bacteria fall into this category

Eukaryotic cells

Contain a nucleus and other organelles that are bound by membranes.

Plasma (cell) membrane

a flexible boundary of a cell that is made up a phospholipid bilayer; in all cells

selectively permeable

controls what passes in or out

Cytoplasm

A jellylike fluid inside the cell in which the organelles reside; in every cell

ribosomes

where proteins are made; in every cell

where can you find ribosomes?

Rough ER and cytoplasm

What must all cells have?

Cytoplasm, cell membrane, genetic material, ribosomes, cytoskeleton

Nucelus

Control center of the cell that holds DNA; in all eukaryotic cells

DNA

directions to make proteins; in all cells

Chromosomes

condensed DNA

chromation

uncondensed DNA

Nucleolus

dense area inside nucleus that produces ribosomes; in all eukaryotes

Endoplasmic Reticulum (ER)

tubes and channels that transport materials throughout the cell; in all eukaryotes

smooth ER

ER that has no ribosomes

rough ER

ER that is dotted with ribosomes

Golgi apparatus

after proteins and lipids arrive in vesicles they go here to be packaged and shipped; in all eukaryotic cells

vesicle

sacs that move through the cytoplasm in and out of the cell; in all eukaryotes

Lysosomes

sacs filled with powerful digestive enzymes that digest things like worn out cell parts; only in animal cells

central vacuole

used for storage of water, minerals, and salts in a plant cell; only in plant cells

Mitochondria

produces ATP for the cell by breaking down glucose (cellular respiration); in all eukaryotic cells

Chloroplast

does photosynthesis and creates the pigment chlorophyll which makes plants green; only in plant cell

cell wall

strong, supporting layer around the cell membrane; in plant, fungi, bacteria, and some protist cells

Cytoskeleton

gives the cell shape, organization, and structure; present in all cells

What is the cytoskeleton made of?

microtubules, microfilaments, intermediate fibers

Centrioles

helps separate chromosomes during mitosis; only in animal cells

Flagella

whiplike tails structure for movement; only found in some types of cells but can be found in both prokaryote and eukaryote

cilia

short hair-like extensions for movement and sometimes feeding; only found in some types of cells but can be found in both prokaryote and eukaryote

What makes eukaryotes different from prokaryotes?

has a nucleus and more organelles

What makes prokaryotes different from eukaryotes?

they have no nucleus and they are less complex

what makes an animal cell different from a plant cell?

has lysosomes, centrioles, more circular in shape, and has no cell wall, chloroplasts, or central vacuole

what makes a plant cell different from an animal cell?

has a cell wall, chloroplast, and central vacuole, more rectangular in shape

Robert Hooke

looked at a cork through a microscope and found cells and named them cells

Anton van Leeuwenhoek

made first simple microscope and looked at pond water through it and saw the first living cells

Robert Brown

discovered the nucleus

M.J. Schleiden

said plants are made of cells

Theodor Schwann

said all animals are made of cells

Rudolf Virchow

proposed that new cells are formed only from cells that already exist ("every cell from a cell")

endosymbiotic theory

eukaryotic life began when a prokaryotic cell took up residence inside another prokaryotic cell and evolved into mitochondria and chloroplasts

what evidence do we have to support the endosymbiotic theory?

both have their own DNA and ribosomes that resembles eukaryotic structure, same size and shape, have two membranes inner membrane was their own membrane and the outer was the membrane of the cell they resided in

what are the levels of multicellular organisms?

cell, tissue, organs, organ system, organism

what are the five kingdoms?

Monera, Protists, Plants, Fungi, Animals

functions of proteins

build strong structures, transport things things throughout the body, speed up chemical reaction

elements in proteins

C, H, O, N, S

what is the monomer of proteins?

amino acids

how many types of amino acids are there?

20 types

what are the three parts of amino acids?

amino group (NH2), carboxyl group (COOH), "R" group

What are the polymers of proteins?

proteins; polypeptides

what are the bonds between amino acids called?

peptide bonds

enzymes

speed up chemical reactions by lowering activation energy

substrate

the molecule entering a reaction

activation energy

Energy needed to get a reaction started

lock and key

each enzyme is specially designed for one type of substrate

denature

to lose its shape irreversibly

primary structure of protein (1°)

sequence of amino acids

secondary structure of protein (2°)

hydrogen bonds form between different amino acids cause strain to form helix or pleated sheet shape

tertiary structure of protein (3°)

R-groups interact causing folding (last stage for some proteins)

quaternary structure

2 or more amino acid chains join together (not all proteins reach this stage)

active site

a region on an enzyme that binds to a protein or other substance during a reaction.

what is the function of nucleic acids?

store genetic code that tells cells how to make proteins in the form of a code

what are the elements in nucleic acids?

C, H, O, N, P

what are the monomers of nucleic acids called?

nucleotides

what are the three parts of a nucleotide?

a nitrogen base, a sugar, and a phosphate group

what are the letters of the nitrogen base for DNA?

G,A,C,T

what are the letters of the nitrogen base for RNA?

G,A,C,U

what are the polymers for nucleic acids

DNA and RNA