Markings of the Axis Bone:

1. Body or centrum (Corpus vertebrae) is a cylindrical mass on anterior side of the vertebra. It articulates with body of the vertebra below (C3).
2. Odontoid process or dens (Dens axis) is a prominent rounded superior projection from the body.
   This tooth-like elevation serves a stable point around which the atlas bone rotates (Gr., odous, tooth).
3. Superior articular facet (Facies articularis superior) is a smooth, sightly convex surface that articulates with the inferior articular facet on the altas bone above (C1)

The atlas is the first cervical vertebra and articulates with the occiput of the head and the axis (C2). It differs from the other cervical vertebrae in that it has no vertebral body and no spinous process. Instead, the atlas has lateral masses which are connected by an anterior and posterior arch.

Anaerobic respiration generates less energy because only glycolysis occurs which forms 2ATP molecules.
However in aerobic repiration there is krebs cycle taking place which is responsible for making around 30 ATP molecules. In total, aerobic respiration generates 36-38 ATP molecules.

Cytoplasmic streaming also called protoplasmic streaming or cyclosis refers to the streaming of cytoplasm inside a living cell. This motion enables materials to reach all parts of a cell including oxygen and nutrients.

The absence of any element necessary for the nourishment of that particular plant will lead to the morphological changes. And this change is an indication of a deficiency.

Of course, if the deficient element is provided to the plant in good time, the symptoms of deficiency disappear. However, if the process is delayed, eventually the plant will die.

Root nodules are found on the roots of plants, primarily legumes, that form a symbiosis with nitrogen-fixing bacteria. Under nitrogen-limiting conditions, capable plants form a symbiotic relationship with a host-specific strain of bacteria known as rhizobia. Nodules are formed as a result of infection of the roots by soil bacteria. ... The complex process by which plant roots are infected by rhizobia is known as infection. The complex process in which nodules are formed is known as nodulation.

Glycolysis produces 2 ATP, 2 NADH, and 2 pyruvate molecules: Glycolysis, or the aerobic catabolic breakdown of glucose, produces energy in the form of ATP, NADH, and pyruvate, which itself enters the citric acid cycle to produce more energy. Cellular respiration has a potential to produce between 36 and 38 moles of ATP per mole of glucose (C6H12O6). ... Each NADH [from glycolysis] produces a net 1.5 ATP (instead of usual 2.5) due to NADH transport over the mitochondrial membrane. Glycolysis has mainly two parts: First part converts glucose to Fructose, consuming 2 ATP. Second part converts the fructose into pyruvate, producing 2 ATP (the process occurs twice, so it producing a total of 4 ATP)

Nicotinamide adenine dinucleotide phosphate, or NADP+, is a similar molecule with a similar function, differing from NAD+ in that it contains an additional phosphate group. The oxidized form is NADP+, while the reduced form is NADPH. The function of NAD+ that is similar to that of NADP+ is that each NAD+ accepts a pair of high-energy electrons. Describe glycolsis in terms of energy input, energy output, and net gain of ATP. In glycolysis, glucose is converted to molecules of pyruvic acid. ... NAD becomes NADH. The main role of NAD+ in metabolism is the transfer of electrons from one molecule to another. Reactions of this type are catalyzed by a large group of enzymes called oxidoreductases.

Hyoid bone, U-shaped bone situated at the root of the tongue in the front of the neck and between the lower jaw and the largest cartilage of the larynx, or voice box. The primary function of the hyoid bone is to serve as an anchoring structure for the tongue. It has no articulation with other bones.

XYY syndrome is a genetic condition that occurs when a male has an extra copy of the Y chromosome in each of their cells (XYY). Sometimes, this mutation is only present in some cells. Males with XYY syndrome have 47 chromosomes because of the extra Y chromosome. Most cases of 47,XYY syndrome are not inherited. The chromosomal change usually occurs as a random event during the formation of sperm cells. An error in cell division called nondisjunction can result in sperm cells with an extra copy of the Y chromosome.

Boys with XYY syndrome may have some or all of these physical symptoms to some degree:

• taller than average height.
• low muscle tone, or muscle weakness (called hypotonia)
• very curved pinky finger (called clinodactyly)
• widely spaced eyes (called hypertelorism)
• cystic acne during adolescence.

Selective reabsorption is the process whereby certain molecules (e.g. ions, glucose and amino acids), after being filtered out of the capillaries along with nitrogenous waste products (i.e. urea) and water in the glomerulus, are reabsorbed from the filtrate as they pass through the nephron.  Feedback mechanism refera to a syatem in which hormones are regulated according to demand. Example-when blood sugar level is high in body,message is sent to Feeback mechanism to regulate more Insulin and when required level is reached secretion becomes normal.

Parenchyma are thin-walled round or oval shaped cells having spaces between them.

It is present in stem, leaves, flowers, fruits and seeds.
Most of them contain leucoplast and store food.
Chloroplast containing parenchyma is called chlorenchyma  and deal with photosynthesis.

Heterodont : It is the condition of having different types of teeth. For example humans have four different types of teeth namely incisors, canines, molars and premolars.

Diphyodont : The type of dentition characterised by two sets of teeth. First set is of temporary and second is of permanent.

Panthera leo  is the scienctific name of lion.

Negative feedback mechanism: 

Whenever there is a change in the normal state, the messages are sent to ‘increase’ secretions if there is a fall below normal or to ‘decrease’ secretions if there is a rise above normal to restore the normal body state. Such a mechanism is called a negative feedback mechanism.

Appendicular skeleton comprises of limb bones and girdles. Limb bones are again divided into bones of forelimbs and bones of hindlimbs. Girdles comprises of pectoral girdle and pelvic girdle

Limb Bones

• There are two pairs of limbs—a pair of forelimbs and a pair of hind limbs.
• Each fore limb is made of 30 bones.
• Bones of the forelimbs are

• Each hind limb is made of 30 bones.
• Bones of the hind limbs are

Pectoral Girdle

• The pectoral girdle is formed of two identical halves.
• Each half of the girdle consists of the following bones — scapula and clavicle.

• Scapula:
• The scapula is also called the shoulder bone.
• It is the flat, triangular bone located at the back of the thorax.
• It has a slightly elevated ridge called the spine.
• The spine projects as a flat, expanded process called the acromion.
• Below the acromion is a cup-shaped cavity called the glenoid cavity.
• The glenoid cavity articulates with the humerus of the forelimbs.
  • Clavicle:
  • It is also called collar bone.
  • It is a rod-shaped bone extending between the neck and the shoulder.

Pelvic Girdle

• It is made of two coxal bones.
• Each coxal bone comprises three bones—ilium, ischium and pubis.

• At the point where all the three bones fuse is a depression called the acetabulum. The head of the femur articulates with the acetabulum.

A line of fusion called the pubic symphysis is observed where the two halves meet

• The vascular system consists of complex tissues, the phloem and the xylem.
• The xylem and phloem together constitute vascular bundles.
• In dicotyledonous stems, cambium is present between phloem and xylem, such vascular bundles because of the presence of cambium possess the ability to form secondary xylem and phloem tissues, and hence are called open vascular bundles.
• In the monocotyledons, the vascular bundles have no cambium present in them, hence they do not form secondary tissues and they are referred to as closed vascular bundles.

Rh grouping

• The Rh antigen similar to one present in Rhesus monkeys is also observed on the surface of RBCs of majority of humans, hence the antigen is known as Rh antigen.
• The individuals having Rh antigen are called Rh positive (Rh+ve) and those in whom this antigen is absent are called Rh negative (Rh-ve).
• An Rh-ve person, if exposed to Rh+ve blood, will form specific antibodies against the Rh antigens, and hence Rh group should also be matched before transfusions.
• A special case of Rh incompatibility has been observed between the Rh-ve blood of a pregnant mother with Rh+ve blood of the foetus , which leads to a disease known as erythroblastosis foetalis.
• Rh antigens of the foetus do not get exposed to the Rh-ve blood of the mother in the first pregnancy as the two bloods are well separated by the placenta, during the delivery of the first child, maternal blood may get exposed to small amounts of the Rh+ve blood from the foetus and the mother starts preparing antibodies against Rh in her blood.
• In case of subsequent pregnancies, the Rh antibodies from the mother (Rh-ve) can leak into the blood of the foetus (Rh+ve) and destroy the foetal RBCs, which cause severe anaemia and jaundice to the baby leading to a condition known erythroblastosis foetalis.
• Erythroblastosis foetalis can be avoided by administering anti-Rh antibodies to the mother immediately after the delivery of the first child.