Organelle Ultrastructure (Nucleus, Mitochondrion, Chloroplast)

Eukaryotic cell

Cells that contain membrane-bound organelles. This includes the nucleus and other organelles such as mitochondria and chloroplast

Ultra structure

Cellular structures of a biological specimen. That can only be seen by an electron microscope. They are all inside nucleus

Histones (Proteins)

Help to fold DNA so it fits into the cell

Chromatin

1. DNA and proteins that are loosely coiled. The DNA is loosely wrapped around the protein (histone)

2. For replication, you must have tightly wrapped chromosomes

3. When DNA is stored, it’s stored as chromatin

3 Organelles that contain DNA

1. Nucleus, long linear and is associated with histone proteins

2. Mitochondria, short circular and is not associated with histone proteins

3. Chloroplast, short circular and is not associated with histone proteins

Functions of Nucleus

1. Controls cell activities

2. Makes RNA

3. Makes ribosome

4. Holds DNA

5. Where DNA replication occurs

Nuclear envelope

Double-membrane that surrounds nucleus, controls entry and exit of materials

Nuclear pore

Allow passage of larger molecules, such as mRNA

Nucleoplasm

1. Jelly like fluid, that makes up the nucleus

2. Contains chromatin (DNA and histones), and nucleolus

Chromatin

Protein (histone) bound loosely wrapped linear DNA

Nucleolus

Within the nucleoplasm, manufactures ribosomal RNA, and assembles ribosomes (makes ribosomes)

Functions of Ribosomes

Makes proteins

Ribosomes

1. Has 2 different sizes

2. 80s, in eukaryotic cells

3. Smaller 70s, in prokaryotic cells, or inside organelles.

Functions of mitochondria

1. Production of energy, with ATP

2. Aerobic Respiration

Double membrane (Mitochondria)

1. Has a folded inner membrane (forms cristae) and a smooth outer membrane

2. Controls the passage of entry and exit of materials

Cristae

1. Formed by the folded inner membrane

2. It’s got a large surface area, for attachment of enzymes and proteins involved in respiration

Matrix

1. Jelly like fluid

2. makes up remainder of mitochondrion

3. Contains proteins, lipids, ribosomes and DNA

Mitochondrial DNA

Short circular DNA, that codes for important enzymes

Ribosomes (70s) (Mitochondria)

Makes proteins

Functions of chloroplast

1. Carry out photosynthesis

2. Produce glucose

Double membrane (Chlorophlast)

Controls exist and entry of materials

Thylakoid

Has pigments and chlorophyll’s, where photosynthesis occurs

Grana

1. Entire stack of thylakoids = Grana

2. Stakes of disc like structures called thylakoids. Within it contains chlorophyll (where light is absorbed)

Stroma

Jelly like fluid, where second stage of photosynthesis takes place. (Synthesis of sugars)

Chloroplast DNA

Short circular DNA that codes for important enzymes

Ribosomes (70s) (Chloroplast)

Makes proteins

Starch grains

It’s stored as energy. As it’s insoluble