IB Bio HL йоу

Stargardt disease

is a degenerative disease of the eye (retinal cells) leading to blindness. Human embryonic stem cells are obtained from unsuccessful in vitro fertilizations. These cells are differentiated in the lab towards retinal cells and injected into the eye of patients. The new cells replace the degenerate cells in the retina and restore vision

Leukaemia

the cancer of white blood cells (immune cells). Human cord blood is collected after childbirth. The cord blood contains stem cells that differentiate into white blood cells. A patient with leukaemia is irradiated and given chemotherapy to kill all cancerous white blood cells. The killed cells are then replaced by the matching cord blood cells which are able to differentiate into all kinds of white blood cells in the patient

Compartmentalization

the separation of a cell's interior into distinct compartments

Homeostasis

Living things maintain a stable internal environment

Nutrition

Living things exchange materials and gases with the environment

Excretion

Living things exhibit the removal of waste products

Lysosomes

membrane-bound organelles, found in eukaryotic cells, that contain digestive enzymes responsible for breaking down waste materials, cellular debris, and foreign invaders, acting as the cell's "garbage disposal system".

where can dna be in a eukaryotic cell

Chloroplast, mitochondria, nucleus

where can dna be in a prokaryotic cell

Nucleoid, plasmid

rough endoplasmic reticulum (RER)

Centrioles

Chromosome separation during mitosis

Where (organelle) is DNA in eukaryotes?

enclosed in the nuclear membrane

Binary fission

a form of asexual reproduction where a parent cell divides into two identical daughter cells, primarily observed in prokaryotes like bacteria,

Phospholipids Head

glycerol + negatively charged phosphate group

Amphipathic

opposite properties

Polar

uneven distribution of electrons, creating partial positive (+) and negative (-) charges.

Non-polar

even distribution of electrons, no significant charge separation.

Fluid

tails will always be facing tails, and the heads will always face outside, but the position of individual phospholipids in a layer may change

Cholesterol in membrane

keeps the fluidity of the membrane constant at a variety of temperatures. When it is cold, it increases fluidity and when hot, it makes the membrane more rigid(solid)

Semi-permeable

only certain molecules (small, polar) can freely cross the membrane

Selective

with the use of transport proteins, it can select what comes in and out and what does not

Active transport

low conc - high conc

Passive transport

high conc - low conc

supercoil

Cytokinesis

he process where a cell's cytoplasm divides, resulting in two daughter cells, completing the final stage of cell division after nuclear division (mitosis or meiosis

Photolysis

Terminal differentiation

G0, a cell permanently exits the cell, no longer divides

G1

cell grows , performance of its daily functions.

Grow in size

Specific enzymes are produced

DNA base units are accumulated (накапливаются)

S

Chromosome number is doubled, DNA synthesis, (replication), gets ready for mitosis

G2

last preparations for mitosis: the cell duplicates its organelles and prepares enzymes and proteins needed for mitosis

Cyclins

a group of stress-sensitive proteins in controlling cell death and survival in DNA damage response / regulate the cell cycle

what will influence the progression of the cell cycle.

An increase or decrease in the concentration of cyclins

Anabolism

synthesis of larger molecules.

Catabolism

breakdown of larger molecules.

Endosymbiosis

prokaryotes evolved first, with eukaryotes likely arising from prokaryotic ancestors

Dimer

a compound made from the bonding of two monomers

Lipids

Can store more energy / not soluble in water