Introns have the non functional code
Answer: See explanation
Explanation:
In meteorology, station models simply refers to the symbolic illustrations which depicts the weather that occurs at a reporting station.
Meteorologists use station model as it helps in revealing and communicating certain information about the weather of a particular area. It also helps in reporting various data and temperatures. .
Answer:
Seminal vesicle
Explanation:
Seminal vesicle secretes an alkaline and viscous fluid that constitutes about 60% of the volume of semen. The fluid secreted by seminal vesicle contains fructose which is a monosaccharide sugar, prostaglandins, and clotting proteins. The alkaline nature of the seminal fluid neutralizes the acidic environment of the male urethra and the female reproductive tract. This is required as the acidic conditions inactivate and kill sperm.
The fructose sugar serves a fuel for ATP production by sperm. Prostaglandins are responsible for sperm motility and viability as they stimulate smooth muscle contractions within the female reproductive tract. Therefore, a malfunctioning seminal vesicle would result in low semen volume and reduced motility due to the scarcity of energy.
Growth and repair
creation of gametes (sex cells)
method of reproduction in unicellular organisms
Binary Fission - type of reproduction that occurs in bacterial cells, single celled organism splits and becomes two identical organisms
Chromosomes and DNA
Chromosomes are DNA wrapped around proteins to form an X-shaped structure.
The diagram will help you see the relationship.
1. Chromosomes are found in the nucleus
2. Chromosomes are made of DNA
3. Sections of chromosomes are called genes
DNA - deoxyribonucleic acid (it is the genetic code that contains all the information needed to build and maintain an organism)
Chromosome Structure
Chromosome Numbers
Each organism has a distinct number of chromosomes, in humans, every cell contains 46 chromosomes. Other organisms have different numbers, for instance, a dog has 78 chromosomes per cell.
Somatic Cells - body cells, such as muscle, skin, blood ...etc. These cells contain a complete set of chromosomes (46 in humans) and are called DIPLOID.
Sex Cells - also known as gametes. These cells contain half the number of chromosomes as body cells and are called HAPLOID
Chromosomes come in pairs, called Homologous Pairs (or homologs). Imagine homologs as a matching set, but they are not exacly alike, like a pair of shoes.
Diploid cells have 23 homologous pairs = total of 46
Haploid cells have 23 chromosomes (that are not paired) = total of 23
Homologous Chromosomes
Sex Determination
Chromosomes determine the sex of an offspring. In humans, a pair of chromosomes called SEX CHROMOSOMES determine the sex.
If you have XX sex chromosomes - you are female
If you have XY sex chromosomes - you are male
During fertilization, sperm cells will either contain an X or a Y chromosome (in addition to 22 other chromosomes - total of 23). If a sperm containing an X chromosome fertilizes an egg, the offspring will be female. If a sperm cell containing a Y chromosome fertilizes an egg, the offspring will be male.
Creation of a Zygote
When two sex cells, or gametes come together, the resulting fertilized egg is called a ZYGOTE
Zygotes are diploid and have the total 46 chromosomes (in humans)
Karyotype
A karyotype is a picture of a person's (or fetus) chromosomes. A karyotype is often done to determine if the offspring has the correct number of chromosomes. An incorrect number of chromosomes indicates that the child will have a condition, like Down Syndrome
Compare the Karyotypes below
Notice that a person with Down Syndrome has an extra chromosome #21. Instead of a pair, this person has 3 chromosomes - a condition called TRISOMY (tri = three)
Trisomy results when chromosomes fail to separate - NONDISJUNCTION - when sex cells are created. The resulting egg or sperm has 24 instead of the normal 23.
Other conditions result from having the wrong number of chromosomes:
Klinefelters Syndrome - XXY (sex chromosomes)
Edward Syndrome - Trisomy of chromosome #13
Answer:
Upon nutrient limitation, budding yeast will produce daughter cells less than 20% of the mother cell size. This asymmetric division may select for growth functions that are efficient over a larger range in cell sizes, such as exponential growth. In turn, efficient growth over a large size range lessens the pressure to have precise size control.
Explanation:
In wild-type cells growing in nitrogen-rich medium, the size threshold to enter mitosis is high, and the G1/S size control is cryptic because cell division produces daughter cells with a size greater than the minimum required to initiate S phase. In these conditions, G2 is long and G1 is short. However, the cell size threshold to enter mitosis is greatly reduced when wild-type cells are shifted to medium with a poor nitrogen source, such as minimal medium with proline, isoleucine, or phenylalanine. In these conditions, wild-type cells initiate mitosis at a reduced cell size, generating two daughter cells that are smaller than the critical size threshold required to progress through G1/S
