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Strokes occur due to problems with the blood supply to the brain: either the blood supply is blocked, or a blood vessel within the brain ruptures, causing brain tissue to die. A stroke is a medical emergency, and treatment must be sought as quickly as possible.
Stroke Warning Signs:-
- Sudden numbness or weakness of the face, arm or leg, especially on one side of the body
- Sudden confusion, trouble speaking or understanding
- Sudden trouble seeing in one or both eyes
- Sudden trouble walking, dizziness, loss of balance or coordination
- Sudden, severe headache with no known cause
- NUCLEUS- It is the control center and assigns all of the other organelles what to do and when to do it. DNA is present inside the nucleus and this material has all the instructions the cell needs for making proteins and the replication procedure. RNA, proteins and other molecules move out of the nucleus into the cell.
- CHROMOSOMES- Chromosomes are found in the nucleus. They are the DNA which is present in the condensed form. They carry the genetic information from the parent to the offspring. During the division phase the DNA condenses into chromosomes and then the duplication of the material takes place.
- RIBOSOMES- Ribosomes help in making proteins, they are small pieces of RNA found in the cytoplasm. Their function is to assemble proteins. They can be found in some other organelles like endoplasmic Reticulum.
- CYTOSKELETON- There is a network of tiny tubes within the cytoplasm; it is called as the cytoskeleton. The tube gives the cell its structure and also supports the organelles by holding them in place. They also work in transporting things between different parts of the cell.
- MICROTUBULES- Cytoskeleton is made from two different components: microtubules and microfilaments. Microtubules are made of protein and are hollow. They help in maintaining the shape of the cell. They form spindle fibers, during the replication process. These spindle fibers help in separating the chromosomes so that they can be divided.
- MICROFILAMENTS- Microfilaments are very thin threads and they are also made of protein. Like the microtubules, they help to maintain the shape of the cell.
- ENDOPLASMIC RETICULUM- They are of two types RER and SER. RER is known as rough Endoplasmic Reticulum. They are a collection of lipid membranes and help in movement of proteins. They are known as rough because the Ribosomes are attached to their surface and give them a rough appearance. The E.R. function is to transports these proteins to another organelle that will help in packaging and will ship them out. SER is known as Smooth Endoplasmic Reticulum. They do not have any Ribosomes on its surface and hence, the name smooth is given. The lipid part of the cell membrane is assembled in SER.
- GOLGI APPARATUS- This organelle looks like stacks of pancakes. They help in packaging and sorting of proteins. The organelle is always around the cell membrane as it is so important to shipping things out of the cell.
- LYSOSOMES- This is the garbage house of the cell. This organelle has digestive enzymes that help in breaking down of items that are toxic to the cell. They help in breaking down the proteins, carbohydrates and lipids.
- MITOCHONDRIA- They is known as the powerhouse of the cell. They have a double membrane and the inner one is folded and thus increases the surface area where energy can be created. They create energy in the form of ATP.
- VACUOLES function is to store water, proteins, carbohydrates and salts. The vacuole is the way the amount of water coming and going is controlled by an organism that lives in water.
- VESICLES are smaller structures found in eukaryotic cells; their function is to store and move things between the organelles.
Animal and plant cell are both eukaryotic cells. They have a nucleus which has the DNA, and they have all the cell organelles. They both reproduce by either mitosis or meiosis. Though plant and animal cells have common characteristics they differ in a variety of ways. Here are the differences between the cells.
- Animal cells are smaller as they are just 10-30 micrometers in length, whereas, plant cells are 10-100 micrometers.
- Plant cells are rectangular in size but the animal cells are found in varied shapes.
- Animal cells have carbohydrates in form of energy but the plant cells have only starch.
- Animal cell lacks a cell wall and only have a cell membrane but a plant cell has both.
- Animal cells have a cylindrical centriole but a plant cell does not have a centriole.
- Glyoxysomes are not found in animal cells, they help in degrading lipids, for the production of sugar.
- Lysosomes are present in animal cells and they help in digesting macromolecules. Plant cells rarely have lysosomes.
- Animal cells lack Plastids but plant cells have them like chloroplast, which is required for photosynthesis.
- The animal cell has small vacuoles but plant cell has vacuoles that cover around 90% of the cell’s volume.
The presence of nucleus and organelles is the basic difference between a prokaryotic and a eukaryotic cell.
Prokaryotic cell lacks nucleus and organelles. The word pro means “primitive” and the karyotic means “nucleus”. They are the most primitive cells and do not have a definite nucleus. Such a type of nucleus is known as a nucleoid. E.g. cyanobacteria. They have various structures inside the cell but they are not encapsulated by membranes.
- These cells are generally smaller in size.
- The plasma membrane may or may not be present
- DNA is low in content and is naked. It is not found in association with histones.
- These cell lack Mitochondria, Golgi Apparatus, Endoplasmic Reticulum. But they have Ribosomes which are 70 S.
- Introns are absent in DNA and RNA. Therefore, they do not require splicing.
- They have chromatin bodies which are scattered inside the cytoplasm.
- They divide through asexual methods of reproduction like binary fission and budding.
- They have pilli and fimbriae for movement of the cell.
- Transcription occurs in the cytoplasm.
Eukaryotic cells have both the nucleus and the cell organelles. These cells have been evolved from prokaryotes. They have a definite nucleus with nuclear material and DNA. These cells have structural organization and enhanced functional efficiency.
Organelles carry the important functions such as the building different molecules, breaking down sugars and removing the waste products. They effectively help to complete all the bodily functions.
- The cells are larger in size.
- The cells have a definitive plasma membrane which is selectively permeable in nature.
- DNA is present in the nucleus and mitochondria. DNA is linear in shape and is found with histones.
- Introns are common and hence, splicing is required before becoming operational.
- Cell organelles like Mitochondria, Golgi Apparatus, Endoplasmic Reticulum are present. They have Ribosomes but they are 80 S.
- The chromatin bodies are enclosed by the nucleus.
- They replicate by using sexual methods of reproduction.
- The eukaryotic cell does not have pilli and fimbriae.
- Transcription occurs inside the nucleus.
Every cell is different but they have the basic structure that is common. All the cell have an outer membrane and inner gel-like material which is known as cytoplasm. All the cells have genetic material that is known as DNA. DNA has the basic information about the cell as passes that information to the offspring. Every cell is different apart from their basic structure.
MEMBRANE– The outer covering which protects the cell is known as plasma membrane. It separates the cell from the outer world. It keeps all the contents of the cell together. The plasma membrane only lets selective material to pass through the cell.
CYTOPLASM– The cytoplasm is responsible for the basic shape and size if the cell. It is the gel-like material present inside the protective membrane. The cell’s organelles are suspended in the cytoplasm.
NUCLEAR MATERIAL– The nucleus is present inside the cell and thus contains the nuclear material. The cells which are prokaryotic lacks nucleus and have nuclear material, whereas the eukaryotic cell has the nucleus which consists of the nuclear material and the DNA.
The cell is a basic structural and functional unit of life. It is the basic unit that makes a life. Every living organism from bacteria to mammals is made up of the cell. The cell is the reason how an organism is able to survive. The group of cells is known as tissue.
Cell biology is a study of the basic unit of life, cell. It is a study of their functions and the subcellular processes. It is a study about the normal working of the cell in a body and how an abnormality can lead to a disease. It is the study in which various cells from different organisms are studied in detail.
There are various kinds of cells. They all differ in the material that is present inside it. Almost all the cells have genetic material, cytoplasm, and a cell membrane. There are various types of cell organelles like mitochondria, ribosomes, Golgi apparatus. Different types of cells have the difference in the structures that are present inside it.
Some organisms are made up of only one cell and hence, are named unicellular organism e.g. Amoeba. All the necessary functions are carried by that one cell. Bacteria’s are mostly unicellular. On the other hand, the human body is made up of trillions of cells. All the cells work together to carry out the bodily functions. Hence, the human is known as a multi-cellular organism.
The basic criteria on which the organisms are divided are on the basis of the cell. The cells are basically grouped into two types- Prokaryotic and Eukaryotic cells.
Prokaryotic cells are found in plants whereas, Eukaryotic cells are found in animals, some plants, and fungi.November 17, 2017 at 4:00 am in reply to: What is the difference between LDL and HDL types of cholesterol? #16184
Types of Cholesterol
There are two main types of cholesterol. LDL and HDL.
Low-density lipoproteins (LDL)
LDL cholesterol are sometimes called “bad” cholesterol because too much is unhealthy. High levels of LDL cholesterol can build up in your arteries, causing heart disease.
Main foods types which supplies LDL cholestrol are:-
- Dairy Foods
- Red Meats
- Lean Protein
- Processed Foods
- Foods Containing Trans Fats.
High-density lipoproteins (HDL)
HDL cholesterols are referred to as “good” cholesterol because it is protective. HDL cholesterol carries cholesterol from other parts of your body back to the liver. Your liver then processes the cholesterol out of your body.
These foods are suppliers of HDL cholestrol:-
- Olive oil
- Beans and legumes
- Whole grains
- High-fiber fruit such as prunes, apples, and pears
- Fatty fish such as salmon, mackerel, albacore tuna and sardines
- This reply was modified 2 years, 8 months ago by ankita.
Answer:- C. Medulla oblongata
Answer:- SkinJuly 17, 2017 at 4:51 am in reply to: Explain how the gynoecium of a flower can be apocarpous or syncarpous. #16146
The gynoecium is the female part of the flower which is made of one or more carpels. So, when there are more than one carpel and they are free they are called apocarpous (as in lotus and rose) while when they are fused it is called syncarpous (as in mustard, tomato)