BIology grade 11 notes
Unit1: Cell functions/ Cell division
Cells
Cell theory:
-All living things are composed of one or more cells.
-The cell is the smallest entity that retains the properties of life.
-New cells arise only from cell that already exists.
Structure of the cell:
The outer boundary (plasma membrane) similar to a city wall
It is constructed with molecules called lipids (fat and oils)
The cell membrane is composed of:
-Proteins and Lipids
-FUNCTION: to allow molecules into and out of the cell. It allows free passages of different types of molecule. SELECTIVELY PERMEABLE.
THE POWER STATION
Mitochondria converts’ fuel
-the most common fuel consume is sugar (glucose)
- The energy is generated through a chemical process called cellular respiration.
- it breaks down sugar to release energy into small molecules called adenosine triphosphate (ATP)
- More active = more mitochondria will contain ex) muscle cells contain more mitochondria than fat.
COMPARTMENTS
Outer membrane similar to the city walls to separate different compartments.
THE NUCLUES
Nucleus is found in the centre of the cell. The control centre of the cell.
Classified in two ways : Eukaryotic ( no true nucleus) or Prokaryotic (true nucleus)
Inside the nucleus is where the chromosomes are found. (long threads of genetic instructions)
Units of chromosomes are determined through genes.
Chromosomes composed of nucleic acids and proteins called DNA
Copied DNA are called RNA which are used to make proteins.
THE FACTORY
Proteins are manufactured in different types.
RNA -> CYTOPLASM -> GOES IN WITH RIBOSOMES (builds proteins) This is composed with smaller protein molecules called amino acids (20)
TO DO A JOB DONE -> NUCLUES -> SET INTRUCTIONS (DNA) -> RNA (PHOTOCOPY) -> RIBOSOMES (FACTORY) -> PROTEINS
GOLGI BODY (ORGANELLE)
Golgi apparatus packages proteins in membranous sacs.
Vesicles are proteins filled sacs
It travels from plasma towards the outside of the
Cells
Cell theory:
-All living things are composed of one or more cells.
-The cell is the smallest entity that retains the properties of life.
-New cells arise only from cell that already exists.
Structure of the cell:
The outer boundary (plasma membrane) similar to a city wall
It is constructed with molecules called lipids (fat and oils)
The cell membrane is composed of:
-Proteins and Lipids
-FUNCTION: to allow molecules into and out of the cell. It allows free passages of different types of molecule. SELECTIVELY PERMEABLE.
THE POWER STATION
Mitochondria converts’ fuel
-the most common fuel consume is sugar (glucose)
- The energy is generated through a chemical process called cellular respiration.
- it breaks down sugar to release energy into small molecules called adenosine triphosphate (ATP)
- More active = more mitochondria will contain ex) muscle cells contain more mitochondria than fat.
COMPARTMENTS
Outer membrane similar to the city walls to separate different compartments.
THE NUCLUES
Nucleus is found in the centre of the cell. The control centre of the cell.
Classified in two ways : Eukaryotic ( no true nucleus) or Prokaryotic (true nucleus)
Inside the nucleus is where the chromosomes are found. (long threads of genetic instructions)
Units of chromosomes are determined through genes.
Chromosomes composed of nucleic acids and proteins called DNA
Copied DNA are called RNA which are used to make proteins.
THE FACTORY
Proteins are manufactured in different types.
RNA -> CYTOPLASM -> GOES IN WITH RIBOSOMES (builds proteins) This is composed with smaller protein molecules called amino acids (20)
TO DO A JOB DONE -> NUCLUES -> SET INTRUCTIONS (DNA) -> RNA (PHOTOCOPY) -> RIBOSOMES (FACTORY) -> PROTEINS
GOLGI BODY (ORGANELLE)
Golgi apparatus packages proteins in membranous sacs.
Vesicles are proteins filled sacs
It travels from plasma towards the outside of the