CELL

Biochemistry =

study of the chemical basis of life, including cellular constituents and reactions/processes.

Nucleus

DNA/RNA synthesis;

ribosomal subunit assembly

Ribosome

Protein synthesis. Human cells: 80S; bacteria: 70S.

Rough ER

Ribosome-studded; major site of protein synthesis.

Smooth ER

Lipid synthesis + detoxification.

Golgi

Modifies + packages proteins; secretion;

links sugars to cellular components.

Secretory vesicle

Carries cell products; formed by Golgi; exocytosis

Lysosome .

Hydrolytic enzymes;

digestion of material taken into cells

Peroxisome

Hydrogen peroxide metabolism;

alpha-oxidation of fatty acids

Mitochondrion

Energy-yielding oxidation + major ATP synthesis;

own DNA;

inner membrane = ETC;

matrix = Krebs/TCA.

Microtubule

Cell support, chromosome movement, cilia/flagella.

Centriole

Chromosome movement during cell division.

Cilia

Move substances across cell surfaces

Flagella

Propel sperm cells.

Microvilli

Increase surface area

Vacuole

Storage/secretory/excretory cavity;

larger in plants.

Prokaryote

No definite nucleus = DNA in nuclear region

Ribosomes = 70S

Cell wall = Bacteria: peptidoglycan/murein

Mitochondria = Absent

ER = Absent

Eukaryote

Distinct membrane-bound nucleus

Ribosomes = 80S

Cell wall = Human: none; fungi chitin; plants cellulose

Mitochondria = Present

ER = Present

Alpha oxidation

Beta oxidation

= peroxisome, especially phytanic acid/VLCFA.

= mitochondria.

TRANSPORT
Primary active

with ATP

Against concentration gradient

TRANSPORT

Secondary active

Indirect ATP

Can be against or along gradient;

uses energy from primary transport.

Example: SGLT Na+- glucose transport.

TRANSPORT

Pinocytosis

Vesicular

Cell drinking; liquid molecules.

Phagocytosis

Vesicular Cell eating;

particulate material

Vesicular transport

No simple diffusion

Useful for high-MW, lipid-soluble compounds such as vitamins/hormones in the source.

CELL CYCLE + CELL DIVISION

G1

Growth

CELL CYCLE + CELL DIVISION

S

DNA synthesis/replication

CELL CYCLE + CELL DIVISION

G2

Growth and preparation for mitosis

CELL CYCLE + CELL DIVISION

M

Mitotic phase/cell division

MITOSIS

Prophase

Chromosomes condense;

each has 2 sister chromatids.

MITOSIS

Prometaphase

Nuclear envelope breaks down;

chromosomes attach to spindle

MITOSIS

Metaphase

Chromosomes align at cell equator.

MITOSIS

Anaphase

Sister chromatids separate toward spindle poles

MITOSIS

Telophase

Chromosomes decondense;

new nuclear envelopes form.

Mitosis

ROLE = Cell multiplication

WHERE = Somatic cells

PRODUCTS = Diploid; 46 chromosomes

Meiosis

ROLE = Sex-cell division

WHERE = Sex cells

PRODUCTS = Haploid; 23 chromosomes

Trisomy 13

Patau syndrome

Trisomy 18

Edwards syndrome

Trisomy 21

Down syndrome

XXY

Klinefelter syndrome

XO

Turner syndrome

XXX

Superfemale