4.4 The Endomembrane System and Proteins

Both the mitochondria and the chloroplasts contain ribosomes.

There is strong evidence that explains the explanation.

Symbiosis is a relationship in which organisms from different species depend on each other for survival.

There is a beneficial relationship in which one organisms lives inside the other.

Nature has a lot ofycorrhizal relationships.

The human gut has microbes that produce vitamins K and K. The relationship is beneficial for us because we can't make vitamins K and K2 in our body.

Scientists have noticed that the organisms are the same size.

We know thatbacteria have the same genes as mitochondria and chloroplasts.
When host cells eat aerobic and autotrophicbacteria, they formed a relationship with each other, but they did not destroy them.
The aerobic and autotrophicbacteria became specialized in their functions through millions of years of evolution.

vacuoles are essential components of plant cells.

Water leaves the central vacuoles and cytoplasm when the water concentration in the soil is lower than in the plant.
The cell wall is supported by the central vacuole.

The cell's expansion is supported by the central vacuole.

When the central vacuole holds more water, the cell becomes larger.

A group of cells that work together to modify, package, and transport lipids and proteins is called the endomembrane system.

We will cover the nuclear envelope, lysosomes, and vesicles soon.
Although not technically within the cell, the plasmamembrane is included in the endomembrane system because it interacts with the other endomembranous organelles.
The system does not include the mitochondria or the chloroplasts.

The rough reticulum is where the secretory and Membrane proteins are made.

Sometimes the RER modifies genes.
In this illustration, an attachment of a purple carbohydrate modifies a green component of the ER.

The Golgi's cisternae is where theProtein passes along.

A portion of the cell's outer shell becomes an important part of the cell's inner shell.

The rough ER and smooth ER are separate areas of the ER.

The ER tubules have a hollow portion.

The nuclear envelope is continuous with the ER's membrane.

The rough reticulum is shown in the transmission electron micrograph.

Structural modifications, such as folding or acquiring side chains, occur when ribosomes transfer their newly synthesized proteins into the RER's lumen.

The ER or the ER's or other organelles' membranes are incorporated into these modified proteins.
The cell can release the proteins from it.
The RER makes conjugates for the cell.

The transport vesicles that bud from the RER's Membrane will be used to reach the destinations of the modified proteins if they are not destined to stay in the RER.

You would be correct in assuming that the RER is abundant in the cells that produce the proteins that are modified by the RER.

This is the case with cells from the body.

The functions of the SER include synthesis of cholesterol, steroid hormones, and storing calcium ion.

In muscle cells, the sarcoplasmic reticulum is responsible for storing calcium ion that is needed to initiate the muscle cells' coordinated contractions.

You can watch an animation.

There is a short assessment at the end of the animation.

In the United States, heart disease is the leading cause of death.

Our sedentary lifestyle and high trans-fat diet are to blame.

There are many disabling heart conditions.

Heart failure doesn't mean the heart has stopped working.

It means that the heart can't pump enough blood to all the vital organs.

If left unaddressed, heart failure can lead to organ failure.

The heart's wall is made of cardiac muscle tissue.

Cardiac muscle cells' reticula do not function as they should.
A sufficient contractile force can be triggered by an insufficient number of calcium ion.

Doctors who specialize in treating heart diseases are called cardiologists.

An electrocardiogram, a test that measures the heart's electrical activity, a chest X-ray, and other tests can be used to diagnose heart failure.

The transport vesicles need sorting, packaging, and tagging before they reach their final destination.

The Golgi apparatus in this white blood cell is visible as a stack of flattened rings in the lower portion of the image.

There are several vesicles near the Golgi apparatus.

The trans face is on the other side.
The transport vesicles that formed from the ER travel to the cis face and empty their contents into the Golgi apparatus' lumen.
Modifications are made to the Golgi that allow them to be sorted.
Adding short sugar molecule chains is the most frequent modification.
These newly modified proteins and lipids are tagged with small Molecules in order to travel to their destinations.

The secretory vesicles that bud from the Golgi's trans face are packaged into the modified and tagged proteins.

While some of these vesicles deposit their contents into other cell parts where they will be used, other secretory vesicles release their contents outside the cell.

In an example of form following function, cells that engage in a lot of secretory activity have an abundance of Golgi.

In plant cells, the Golgi apparatus has an additional role of synthesizing some of the polysaccharides that are incorporated into the cell wall and some of the other cell parts.

There are many diseases that are caused by genetic defects.

Lowe disease is a disease that affects the eyes, brain, and kidneys.
There is a deficiency in the Golgi apparatus in Lowe disease.
Children with Lowe disease are usually born with cataracts and may have impaired mental abilities after the first year of life.

Lowe disease is caused by a variation on the X chromosomes.

The X and Y chromosomes are used to determine a person's sex, as females and males have two X and one Y chromosomes.
Only one of the two X chromosomes is expressed in females.
Females who carry the Lowe disease gene on one of their X chromosomes do not show symptoms of the disease.
The genes on the X chromosomes are always expressed in males.
Men will always have Lowe disease if their X chromosomes carry the Lowe disease gene.
Many of the locations that cause genetic diseases have been identified by geneticists.
A woman can find out if the fetus she is carrying is afflicted with a genetic disease with the help of prenatal testing.