Basic Genetics And Biochemistry of Inheritance Flashcards
is made up of several structural organelles enclosed in the plasma
membrane, that enable it to function properly, eliciting mechanisms that benefit the host (animal).
Animal cell
This is a thread-like structure of nucleic acids and protein
found in the nucleus of most living cells, carrying genetic information in the form of genes.
Chromosomes
the study of inheritance in relation to the structure and function of
chromosomes.
Cytogenetics
this the production of gametes from haploid precursor cells.
Gametogenesis
is the study of chromosomal structure, location and function in cells. It includes the study of chromosome number and appearance (karyotyping), the physical location of genes on chromosomes, and chromosomal behavior in processes such as cell division.
Cytogenetics
This is a protective membrane that protects and covers
animal cell and membrane organelles including cell nucleus.
Cell membrane
-This is a thin semi-permeable membrane
-It contains a percentage of lipids making a semi-permeable barrier between the cell and its physical environment.
-It has also some protein components
-It is very consistent around the cell
-All living cells have a plasma membrane.
Structure of plasma membrane ( cell membrane)
To enclose and protect the cell content
To also regulate the molecules that pass into and out of the cell, through the plasma membrane. Therefore it controls homeostasis.
The proteins are actively involved in transporting materials across the membrane
The proteins and lipids allow cell communication, and carbohydrates (sugars and sugar chains), which decorate both the proteins and lipids and help cells recognize each other
Function of plasma membrane ( cell membrane)
This is a spherical structured organelle found majorly at the center of a cell surrounded by a double-layered nuclear membrane separating it from the cytoplasm.
Nucleus
The double-layered membrane is a continuous channel of membranous from the endoplasmic reticulum network.
The membrane has pores which allow entry of large molecule
Nucleoli (Singular; nucleolus) are tiny/small bodies found in the nucleus
The nucleus and its component organelles are suspended in thenucleoplasm (House of the chromosomal DNA and genetic materials)
Structure of Nucleus
Function of Nucleus
The primary role of the nucleus is to control and regulate cell activities of growth and maintain cell metabolisms.
It also carries the genes that have hereditary information of the cell.
The chromosomal DNA and genetic materials, which are made up of genetic coded ultimately make up their proteins’ amino acid sequences for use by the cell.
Therefore, the nucleus is the information center.
It is the site for Transcription (formation of mRNA from DNA) and the mRNA is transported to the nuclear envelope.
This is a gel-like material that contains all the cell organelles, enclosed within the cell membrane.
Cytoplasm
These are membrane-bound organelles located in the cytoplasm of all eukaryotic cells
Mitochondria
Structure of mitochondria
They are rod-shaped or oval or spherically shaped, with a size of 0.5 to 10 μm.
Mitochondria have two special membranes – outer and inner membrane.
They have a mitochondrial gel-matric in the central mass.
The membranes bend into folds known ascristae.
Functions of Mitochondria
Their primary function is to generate energy for the cell i.e they are the power generators, producing energy in form of Adenosine Tri-phosphate (ATP), by converting nutrients and oxygen into energy enabling the cell to perform its function and to also release excess energy from the cell.
Mitochondria store calcium which assists in cell signaling activity, generating cellular and mechanical heat and mediating cellular growth and death.
The outer membrane is permeable, allowing the transport of small molecules and a special channel to transport large molecules.
The inner mitochondrial membrane is less permeable thus allowing very small molecules into the mitochondrial gel-matrix in the central mass. The gel matrix is composed of the mitochondria DNA and enzymes for the Tricarboxylic Acid (TCA) cycle or the Kreb’s Cycle.
They are small organelles majorly made up of 60% RNA cytoplasmic- granules and 40% proteins.
Ribosomes
Structure of Ribosomes
Ribosomes are made up of ribosomal proteins and ribosomal RNA (rRNA). In a eukaryotic cell, ribosomes constitute half ribosomal RNA and half ribosomal proteins.
Each ribosome is made up of two subunits i. e large subunit and small subunit with their own distinct shapes. These subunits are designated as the 40s and 60s in the animal cell.
Function of Ribosomes
Ribosomes that occur as free particles are attached to the endoplasmic reticulum membrane occurring in large numbers accounting for about a quarter of the cell organelles. A single replicated cell has about 10 million ribosomes.
The ribosomal subunits are the site for genetic coding into proteins. On the ribosomes, the mRNA helps determine the coding for Transfer RNA (tRNA) which also determines the protein amino acid sequences. This leads to the formation of the rRNA which are involved in the catalyzation of peptidyl transferase creating the peptide bond found between the amino acid sequences that develop the proteins. The formed proteins then detach from the ribosomes, migrating to other cell parts for utilization by the cell.
Structure of Endoplasmic Reticulum( ER)
This is a continuous folded membranous organelle found in the cytoplasm made up of a thin network of flattened interconnected compartments (sacs) that connects from the cytoplasm to the cell nucleus.
Within its membranes, there are membranous spaces called the
Cristae spaces
Membrane folding are called
Cristae
There are two types of ER based on their structure and the function they perform including
Rough Endoplasmic reticulumand Smooth endoplasmic reticulum.
Function of Endoplasmic Reticulum
Manufacturing, processing and transporting proteins for cell utilization both in and out of the cell. This is because it is directly connected to the nuclear membrane providing a passage between the nucleus and the cytoplasm.
The ER has more than half the membranous cell content, hence it has a large surface area where chemical reactions take place. They also contain the enzymes for almost all the cell lipid synthesis hence they are the site for lipid synthesis.
Called “rough” because there surface is covered with ribosomes, giving it a rough appearance.
Rough Endoplasmic Reticulum
is not associated with ribosomes and their function is different from that of the rough endoplasmic reticulum, despite lying adjacent to the rough endoplasmic reticulum.
Smooth Endoplasmic Reticulum
Also a specialized type of smooth ER and its function is to regulate the concentration of Calcium ions in the muscle cell cytoplasm
Sarcoplasmic reticulum
These are membrane-bound cell organelles found in the cytoplasm of a eukaryotic cell, next to the endoplasmic reticulum and near the nucleus.
Golgi apparatus
Functions of Golgi Apparatus
Their primary function is to transport, modify and pack proteins and lipids into the Golgi vesicles to deliver them to their target sites. Animal cells contain one or more Golgi bodies while plants have a few hundred.
Cis and trans Golgi network make up the outer layer of cisternae at the cis and trans face and they are responsible for sorting proteins and lipids received at the cis face and released by the trans face, by the Golgi bodies.
Adding fatty acids and/or phosphate groups by phosphorylation, and/or removing monosaccharides e.g. the removal of the mannose moieties takes place in the cis and the medial cisternae while adding of galactose takes place in the trans cisternae.
Sorting of the modified proteins and lipids occurs in the trans-Golgi network and packed into the trans vesicles, which then delivers them to the lysosomes or sometimes to the cell membrane for exocytosis. Assisted by ligands bound to receptors triggering fusion and protein secretion.
It is also known as cell vesicles; Lysosomes were discovered by Christian Rene de Duve, a Belgian cytologist in the 1950s.
Lysosomes
Structure of Lysosomes
They are round subcellular organelle found in almost all eukaryotic cells
Lysosomes are very acidic organelles containing the digestive enzymes and therefore each of the lysosomes is surrounded by a membrane to protect it from the outer environment.
Structure of Lysosomes
This is the site for digestion of cell nutrients, excretion, and cell renewal.
Lysosomes break down macromolecules components from the outside of the cell into simpler elements that are transported into the cytoplasm via aproton pumpto build new cell materials.
Structure of Cytoskeleton
Long chains of amino acids
Function of Cytoskeleton
To create network organizing the cell
Meshwork of fibers running parallel
Actin filaments also known as microfilaments
These are long filaments that assist in mitos
Microtubules
They are more stable filaments in comparison to the actin and microtubules
Intermediate filaments
These are long straight, hollow cylinders filaments
Microtubules
Function of Microtubules
Transportation of some organelles like the mitochondria
This is distinctly found in animal cell which has the ability to replicate or make copies by itself.
Centrioles
Structure of centrioles
small structure that is made up of 9 sets of Microtubules
Function of centrioles
Allow the transformation of substances that are link together
Tiny bodies found in the cytoplasm
Peroxisomes
Structure of Peroxisomes
Spherically shape
Function of Peroxisomes
Lipid metabolism
These are locomotive projections found on the surface of the cell.
Cilia and flagella
These are locomotive projections found on the surface of the cell.
Cilia and flagella
These are locomotive projections found on the surface of the cell.
Cilia and flagella
Structure of cilia flagella
Made strands of filament
Function of Cillia and flagella
Allowing sperm cells to swim to the ova for a fertilization
These are vesicles bound by membranes and formed by a mechanism of endocytosis
Endosomes
Function of Endosome
Involves folding in of the plasma membrane
These are fluid filled cell organelles enclosed by membrane
Vacuoles
Function of vacuoles
Function is to store food, water, carbohydrates in the form of sugars and waste materials
These are surface protrusions found in the intestinal lining, on egg cell surfaces, and on white blood cells.
Microvilli
Function of Microvilli
In the small intestines, they increase the surface area for the absorption of digested food and water.
