NCERT 9th Biology Chapter 1 (Cell) Cheat Sheet (DRAFT) by thatgreatestgod

The outermost part, covers the cell.

Separates intra-­cel­lular material from extra-­cel­lular material.

It makes the cell a separate entity.

Helps in transport -> select­ively permeable membrane.

Uses enzymes and amino acids for transport using lock and key mechan­isms.

Made of lipids and proteins.

Methods of transport -

1) Diffusion - O₂ and CO₂ moves through cell membrane. (A sponta­neous movement of a substance from a region of high concen­tration to a region of low concen­tra­tion. (Only if energy is provid­ed.))

2) Osmosis - The movement of water from a region of low solute concen­tration to a region of high solute concen­tration through a select­ively permeable membrane.

3) Active Transport - Nutrition absorption (Requires Energy)

Solutions -

Isotonic solution - Net osmosis = 0

Hypotonic solution - Endosmosis - Water moves in.

Hypertonic solution - Exosmosis - Water moves out.

For the cell membrane, enzymes, and hormones. All are helped by lipids to be made, proteins are also used.

Proteins and lipids and building blocks, they are not combined.

The S.ER of liver cells plays a crucial role in detoxi­fying poisons and drugs.

Storage sacs for solids and liquids.

In plant cells, they are very big and take the central position with occupies. The central vacuole occupies 50% to 90% of the space and displaces the nucleus to the side.

Plant vacuoles have sap which increases rigidity.

Important substances and other things and stored in plant vacuoles. (Amino acids, sugars, organic acids, and proteins)

In amoeba, vacuoles hold food.

it is used for water expulsion also.

Found in plant cells, certain bacteria (cyano­bac­teria - blue-green algae (Can conduct photos­ynt­hes­is)), and fungi (Agaricus) (Made up of cellulose in plants).

Cellulose is a polymer of starch -> sugar.

Surrounds the plasma membrane of plant cells and provides tensile strength and protection against mechanical and osmotic stress.

One of the strongest natural materials on earth, it is not digested easily, this is why herbivores have long digestive systems.

Shrinking due to exosmosis is called plasmo­lysis. The cell wall retains its shape in this phenom­enon. Osmosis can only occurs in living cells.

Cytoplasm and blood plasma are the same. It replen­ishes the cytoplasm.

Plasma contains nutrients and waste.

Cytoplasm is a moving material, it is a platform for cellular activi­ties.

It contains cell organe­lles.

Viruses don't have cytoplasm or cell organe­lles.

In prokar­yotes which lack cell organe­lles, the cytoplasm conducts ATP synthesis and et cetera.

The cytoplasm contains nutrients, diffused CO₂ and O₂, proteins, fats, lipids, and water.

Discovered by Camillo Golgi (Mexic­an/­Spa­nish).

Multiple flat sacs stacked on top of each other. (flat sac - cistern)

Sometimes, they are connected to ER, which makes a very complex membrane system.

it packages proteins (RER) and lipids and sends them out (SER).

ER -> Lipids and proteins -> packaged by GA -> Sent to destin­ation.

In some cells, GA converts simple sugars to complex sugars.

ATP synthesis, Kreb's cycle (2^nd stage)

The powerhouse of the cell.

Contains mitoch­ondrial ribosome which makes RNA which can join to be DNA. It sends them through pores.

It converts pyruvic acid to CO₂ + H₂O -> more ATP.

It has two mitoch­ondrial membranes. The outer membrane is porous, the inner membrane is folded. More surface area for more chemical reactions.

They can produce their own proteins.

Contains nucleolus -> Chromo­somes -> DNA -> Genes

Plays a major role in cellular activities and cell reprod­uction.

Acetoc­armine, safranin, and methylene blue are used for staining cells.

Nucleus had a different chemical compos­ition and appears dark when stained.

Nucleolus is covered by two membranes, its porous from transport.

Nucleolus is made up of chromatin fibres which arrange themselves to form chromo­somes. This only happens during cell division.

Chromatin fibres are made up of DNA (Deoxyribo Nucleic Acid) -> Deoxy Ribose Sugar + phosphate + nitrogen base. It is a chemical chain made up of nucleo­tides. Multiple nucleo­tides make one gene. DNA is a staircase structure. Each step is a nucleo­tide.

If RNA/DNA is suspended in the cytoplasm, it is a prokar­yote. (Nucleoid)

Tubes (sheets) around the nuclear area. It's a large network, it's membra­ne-­bound.

They are like oblong bags or vesicles.

Two types-

Rough ER - Has ribosomes -> proteins -> to the nucleus.

Smooth ER - Doesn't have ribosomes. -> fats and lipids production -> membrane biogenesis -> manufa­cturing and repairing the cell membrane, transport of material through ER.

Sacs filled with digestive enzymes. produced by RER.

Clears cells by digesting all foreign materials and worn-out cell parts.

Lysis - cutting

They burst the membrane and release the enzymes, they are called suicide bags, they will destroy the full cell if it is beyond repair.

Only in plant cells.

Two types -

* Chromo­plast -

It is pigmented, if it is chloro­phyll, then it will be green and called chloro­plast (It conducts photos­ynt­hesis CO₂ + H₂0 -> C₆H₁₂O₆.

It can contain Xantho­phyll (Yellow), Carote­noids (Red, Orange)

* Leucoplast -

Non-pi­gme­nted, white, colorless.

For storage, oils, starch, and proteins.

The grana are connected to the top and bottom. Grana are towers made up of disc-like thylak­oids. Thylakoids have chloro­phyll with traps like in light reaction. Plastids are filled with stroma (liquids). The bridges that connect the grana are called Stroma Lamella

Photos­ynt­hesis is a two-stage process, in grana (First stage, Light reaction (requires light)) and stroma (Second stage, Dark reaction).