Anatomy Unit 2: Cells - Dr.Breslin - SWCTA 23-24

Nucleus, Cytoplasm (cytosol), Cell Membrane

The study of cells

True

False, all cells start out the same but eventually differentiate into specific types of cells.

AKA: phospholipid bilayer - consists of phospholipids and embedded proteins. Function: membrane regulates what enters and leaves the cell. Selectively permeable.

“The brain of the cell” - directs cell activities and contains genetic information (dna) in the form of chromatin

• Nucleolus - responsible for the production of ribosomes

• RNA can exit the nucleus through the nuclear membrane

Cytoplasm (AKA - cytosol) is the area between the nucleus and the membrane. A lot of cell metabolic reactions occur in this area.

It is the transport system. It has canals and channels that connect membranes to the nucleus and to organelles within the cell.

lipid synthesis

It has ribosomes on the surface, so ribosomes make protein

Make protein

Packages and delivers proteins produced by ribosomes, exported by vesicles

Transfers energy from food to a usable form called ATP, this process is called cellular respiration.

It requires glucose (food) and oxygen, process done by mitochondria

Cells lack energy to perform basic life processes (causing disease or other condition)

contain enzymes to break down substances: aka “suicide sack”

Brain damage, jaundice, cataracts, enlarged liver, kidney damage, Tay Sachs: progressive deterioration of nerve cells and mental/physical abilities from 7 months-4 years old.

two cylinders; perpendicular, they form a spindle in cell division.

the spindle moves chromosomes during cell division so that each new cell gets the proper amount.

made of microfilaments and microtubules, for cell shape and support. cilia and flagella are both involved in movement.

Without it, cells wouldn’t be able to bring in needed materials like food and oxygen, or remove waste. All of these occur at the cell membrane/phospholipid bilayer.

• Phosphate head (hydrophilic - attracted to water - polar)

• Fatty acid tail (hydrophobic - repelled by water - nonpolar)

• Arranged as a bilayer, serves as a cellular barries/border

• Fatty acid tails/nonpolar hydrophobic tails are impermeable to polar molecules

Repelled by water

Attracted to water

it can increase the cell’s efficiency of moving substances. Villi (digestive system cell projections) aid in absorbing nutrients with this.

a process where no energy is needed and it goes from high concentration to low concentration

Ex: Diffusion or Facilitated Diffusion (high to low)

Molecules moving from **high-**concentration areas to **low-**concentration

• passive transport

• no energy needed

Diffusion through protein channels

• no energy needed

• passive transport

• high to low concentration

• in PROTEIN CHANNELS

When cells need to go against (low -→ high) concentration gradient (high to low) they use Active transport.

• low to high

• protein “pump”

• REQUIRES ENERGY = ATP

• exocytosis and endocytosis

Active Transport

When things exit the cell: secretion

STUDY GUIDE ANSWER:

• Exocytosis - large particle leave the cell

• Phagocytosis - large solid things (ex: glucose)

• pinocytosis - bringing things in from the outside/liquid things (ex: water)

STUDY GUIDE ANSWER:

• Endocytosis- large particles enter the cell

• Pinocytosis- liquid enters the cell

Study!

The diffusion/movement of water

NEED TO KNOW THESE!!!!

• high water, low solute

• freshwater

• cell gains water

• cell swells, then explodes and bursts

• “KABOOM!”

• low water, high solute

• salt water

• cell dehydrated and dries out

• then dies from no water

• “im shrinking, i’m shriveled!”

• mild salt solution

• equal solute and equal water concentration

• no problems

• no net movement, equal flow

• cell is balanced

• cell is stable

• “im perfect!”

All of life is built on carbon!

They can form 4 stable covalent bonds and can form carbohydrates, lipids, proteins, nucleic acids too!

• These cells are usually 72% H2O and 25% Carbon compounds

• (??? not too sure about this question)

Smaller organic molecules joining together to form larger molecules

4 major classes:

• carbohydrates

• lipids

• proteins

• nucleic acids

Long molecules are built by linking repeating building blocks in a chain

• Dehydration synthesis - adding energy, removing the water

Using dehydration synthesis - you join monomers by “taking H2O out”

• This requires energy and enzymes, takes out the water

• adds energy, removes the water

Digestion: Hydrolysis

• use water/H2O to breakdown the polymer

• uses energy and enzymes

• adds water, releases energy

Monosaccharides (C:H:O | 1:2:1)

Amino acids (CHON, -COOH, -NH2)

glycerol/fatty acids (C:H:O | greater than 2:1 H:O [carboxyl group])

nucleotides (CHONP pentose, nitrogenous base, phosphate)

they store information (like genes and blueprints for building proteins, dna→ rna → protein), gather genetic material, and transfer information for the next generations of new cells

RNA is a ribo-nucleic acid, single helix in shape

True

DNA is deoxyribonucleic acid, double helix in shape

• Nitrogen base - (C-N ring) (a,t,c,g,u part)

• Pentose sugar (5C) - ribose in RNA and deoxyribose in DNA

• Phosphate (PO4) group

• Purines have a double ring N base

• Adenine (A) and Guanine (G)

• Pyrimidlines are single ring N bases

• Cytosine (C) and Thymine (T) and Uracil (U)

A::T (2 H bonds)

G:: C (3 H bonds)

• 20 different amino acids/monomers

• polypeptide/polymers, large and complex molecules, complex 3-D shape

• literally almost everything

• study list

• know they are the most structurally and functionally diverse

• central carbon

• amino group

• carboxyl group (acid)

• R group (side chain) (1 of the 20)

• Primary structure (1)- order of amino acids in chain, sequence determined by DNA/gene, slight change can change function and structure!!

• Secondary structure (2)- local folding, short sections of polypeptides, H bonds, alpha helix or beta pleated sheets (3-D structures in sections)

• Tertiary structure (3)- whole protein/molecule folding, hydrophobic, h bonds and ionic bonds, disulfide bridges

• Quaternary structure (4)- not all proteins, only ones with multiple polypeptide chains, hydrophobix interactions

• temperature, pH, and salinity can disrupt H, ionic bonds, or disulfide bridges

• in 2 and 3 structure it alters their shape

• denaturation destroys functionality, some proteins can return to their functional shape, others cannot

any molecule that has the elements C:H:O in a 1:2:1 ratio.

• simple: made up of one or two monomers

• complex: long polymers (aka: polysaccharides, good fo r storing energy)

one monomer subunit (ex: sugar glucose: C6H12C6

two monosaccharides: ex: sugar sucrose/table sugar - glucose +fructose= sucrose

starch

glycogen

their cell walls

in the exoskeletons

• long term energy storage

• concentrated energy

• cushions organs

• insulates body

F - false, they do not form polymers. Big molecules make smaller subunits, not a continuing chain.

glycerol + a fatty acid

• the fatty acid = the long HC “tail” with COOH (carboxyl group) “head”

• can be seen in dehydration synthesis

• non-polar

• hydrophobic

• 3 fatty acids linked to glycerol

• ester linkage - between OH and COOH

T - helps keep cell membranes fluid and flexible

• its in the animal cell membranes and a precursor of all the other steroids

• high levels of cholesterol in blood may contribute to cardiovascular disease

• keeps cell membranes fluid and flexible

• precursor for steroids

• important component of cell membrane

• 4 fused C rings + (x)

• x can be any functional group

• steroids are formed from cholesterol

• different functional groups → different cellular functions

• Interphase = growth phase (G1, S, G2)

• Mitosis = nuclear division

• Cytokinesis (cell division)

• study diagram

• G0 - non-dividing phase, growth

• G1 - growth phase 1, preparation for DNA Synthesis

• S - DNA replication: DNA must be copied and replicated ensuring the new cells contain the proper amount of dna

• G2 - Preparation for Mitosis, growth

Study! You don’t have to know pre- and mid- just know what the phases look like

• PMAT - prophase, metaphase, anaphase, telophase

• Mitosis - Interphase (1), Prophase (2), Metaphase(3), Anaphase (4), Telophase(5), (Cytokinesis (6))

• Division of the cytoplasm happens to form 2 new daughter cells

• organelles are divided

• daughter cells are genetically identical

• then cells return to interphase to keep replicating!

Chromosomes are made up of a DNA-protein complex called chromatin - study diagram for parts

• visible chromosomes (aka - chromatids)

• centrioles migrate to the poles

• nuclear membrane disappears

• nucleolus disappears

• spindle forms

• chromosomes line up on the equator

• and the spindle attatches

• chromatids seperate at the centromere and move to opposite poles

• think of A for anna in frozen being pulled away bc of her sister elsa

• chromosomes disappear - chromatin

• nuclear membrane reforms

• nucleoli reappears

• spindle disappears

• centrioles duplicate

As cells multiply and organisms develop and grow

Stem cell → then to whatever is needed in the organism

• stem cells can be many different types of cells, each with their own distinct function

By uncontrolled cell division. In normal cells, cell division eventually stops. With cancer cells, their DNA is damaged and never had division stop.

1 from mom, one from dad

True

Telophase

Anaphase

Metaphase