posted Jul 16, 2016, 2:03 PM by Upali Salpadoru
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updated Sep 16, 2017, 12:31 PM
]
M..
This is the way cell divides to produce sex cells. The chromosome number gets halved, Ck\lick cell biology.
This includes all the physical and chemical changes that occur inside a living being. There are two types.
Anabolism:- This includes the formation of complex compounds present in the body.
Catabolism:- the breakdown of complex molecules in living organisms to form simpler ones, together with the release of energy;
Copying of proteins is a very reliable process, yet may one in a million a mistake can occur This would cause a mutation. Most of the errors cause no harm.
The effect caused by the change of the structure in a gene. Only the mutations that may occur in the reproductive cells will be hereditary.
Mutations often lead to evolution. The process may produce an individual more suitable for the environment. N
Non directional movements in plants due to stimuli such as temperature.
The function of nephrons is to remove urea, uric acid, and creatinine, and also any excess sodium, chloride, and potassium ions. It can also re absorb water and useful materials such as glucose and maintain the fluid balance.
This is the inflamation of kidneys due to infection or immunity dis orders.
The place of an organism takes and the role it plays in a particular environment.
- Nucleus
Fig. Structure of the nucleus. This is the most important organelle in a cell.It contains genetic material, chromosomes.
O
A gene found in the chromosomes of tumor cells which is associated with the conversion of normal cells into cancer cells.
This is a structure with specialized functions, in the cytoplasm of an eukaryotic cell.
This occurs when two solutions of un=equal concentration are separated by a semi permeable membrane. Water from the dilute solution diffuses into the more concentrated solution. Usually the solids dissolved cannot pass through the semi permeable membrane. Plants are able absorb dissolved solids only when they are present in a very dilute form. If a plant root come in contact with a concentrated solution, reverse osmosis can occur.
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This is an experiment to demonstrate diffusion. Take two yams carrots or beet root. Make a hole on top as shown Insert a straw and plug it so that water will not leak.
- Add sugar solution to one and plain water to the other. Fill the first glass with water and the other with a sugar solution. Observe what happens after a few hours.
P These are organisms that live or get food from other organisms. There are the ecto parasites that rae found outside the body and endo parasites that live inside.
An off spring produced by the combination of hereditary factors as well as environmental conditions.
- Photosynthesis.
- Synthesis of primary food by the plants. The reaction is explained by this equation.Water +Carbon dioxide + (Energy from sun light) = Glucose + Oxygen.
- 6CO2 + 6H2O (Light energy) = C6H12O6 + 6O2
- This reaction can only be performed by chlorophyll the green substance present in plants.
- Polymerase
an enzyme that can build long chains of DNA or RNA using the nucleotides
Parts of a dicot plant. 
Fig. Structure of Maize (monocot) and Bean (dicot) seeds.
- Polymerase chain reaction
A method developed to get copies of DNA very quickly. PCR was discovered in 1983 by K.B.Mullis. He won the Nobel Prize for Chemistry in 1993.
· PrebioticsPrebiotics are carbohydrates in the intestines which cannot be digested. These help the healthy bacteria, probiotics to flourish.
. R These will become effective only if two copies of the allele are present in an individual. Cystic fibrosis is caused by a recessive allele.
- Reflex action. An involuntary reaction such as the knee jerk.
- Respiration
This process conforms to two important functions. External respiration - What happens outside the cells, described as breathing or ventilation.
Higher animals use lungs for breathing. Lung respiration
Insects use a system of air ducts.
The fish use gills.
Plants exchange gases through stomata.
Cellular respiration – This is the process by which food is oxidised to obtain
energy. There are two important ways of doing this. 1. Aerobic respiration This is the normal respiratory process using oxygen. C6H12O6 + 6O2 = 6CO2 +6H2O +( energy, ATP)
Glucose + Oxygen = Carbon dioxide + Water + (Energy)
2. Anaerobic respiration. - This process does not use oxygen.This still takes place among some lower forms of life. Scientists believe that the earliest forms of life would have used this method as there was no oxygen in the atmosphere then. This does not produce as much energy as the other.
Fermantation by yeast is an example of anaerobic respiration.
ReproductionThe ability to make exact copies of oneself may be considered as the
specific characteristic of living things. There are many ways of performing
this most important task. Let us consider some of them. A = Asexual Methods 1. Fission – This is merely dividing a cell and its contents into two or
more cells. This process is almost identical to growth. Spirogyra, an algae
consists of a row of identical cells. When the cells divide yet they are
attached to the filament we call it growth. If they separate and start life as
new individuals it amounts to reproduction. In the case of amoeba, a protozoan,
binary fission amounts to reproduction. 2. Budding – This is very common in plants and yeast like specimens but rare
among animals. Hydra is a fresh water animal that form new individuals by
budding. 3. Vegetative Propagation-This includes all types of producing new plants
from a parent plant. Here are sme examples. Runners in strawberry. Leaves in
Bryophillum and Begonia. Suckers in
Banana. Bulbs in garlic Stem cuttings in Roses. B- Sexual Method 4. This method involves the formation of gametes from two individuals and
uniting them in a process called fertilization. Gametes contain only half the number
of chromosomes which are formed by Reduction Division of cells. The process is
also called meiosis. The gametes may be similar or differentiated as male and
female. The individual formed by fertilization is called Zygote and would
contain a diploid number of chromosomes. Refer:- Cell division
S These are the un specialised cells that are capable of dividing and becoming any kind of a specialised cell.
These are the opening found on the surface of leaves. The gas exchange for respiration and photosynthesis take place through these openings. Each opening is controlled by two guard cells as it is a disadvantage to lose water, transpiration, through these in times of scarcity.
These are
mechanoreceptors, that feel the extension of various organs and muscles, They are directly linked to the brain stem via afferent
nerve fibers. Examples include stretch receptors in the arm and leg muscles
and tendons.
T - Tendril.
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- An appendage of a creeper to climb up a su[pport. Some times leaves or at times the axillary bud gets modified into a tendril that can search for a twijg and coil round it.
- Fig. shows an entire bud modified into a tendril.
- Territory
The area which an animal or a group of a specie defend, to live and protect their young.
A group of similar cells in a plant or an animal specialised for a purpose. Eg. Blood tissue. Epidermal tissue and vascular tissue in plants.
The growth of a plant towards or away from a stimulus. Eg Phototropism growing towards light. Geo tropism and Hydrotropism are also examples.
Production of protein according to information in m RNA molecule.
TranspirationThis is the loss of water due to evaporation from plants, mainly from the leaves.
Turgor PressureWater enters the plant cells by osmosis. This causes the cell to swell keeping its shape. In the absence of this water cells can collapse.
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