Answer:
True
Explanation:
During contraction of skeletal muscle fibers, the thin filaments slide inward toward the A band's center as a result of cycles of crossbridge binding and bending.
Answer: In vitro fertilization
Explanation:
In vitro fertilization (IVF) involves some procedures used to help with fertility. This series of procedures are usually complex and can help prevent genetic problems and assist with the conception of a child.
During IVF, mature eggs are collected from the female ovaries and sperms from the male and fertilized in the laboratory. The fertilized egg are then transfered back into the uterus for its growth and development.
The sperm and eggs could be from partners who have decided to carry out IVF or from donors. IVF is usually Carried out by high rating laboratory. One full cycle of IVF takes about three weeks. IVF are usually expensive and could take a longer time if splits into different aspects.
IVF is an effective reproductive technology.
Answer:
3 long tails : 1 short tail
Explanation:
This question involves a single gene coding for tail length in mice. The allele for long tail (T) is dominant over the allele for short tail (t). This means that an heterozygous mice will possess the long tail length.
According to this question, in a cross between two hybrid or heterozygote mice i.e. Tt × Tt, the following gametes will be produced by each parent:
Tt - T and t
Using these gametes in a punnet square (see attached image), the following will be produced: TT, Tt, Tt and tt.
Offsprings with genotype TT, Tt and Tt will have a LONG TAIL while genotype tt will have a SHORT TAIL. Hence, the phenotypic ratio will be 3 long tails : 1 short tail.
The correct answer is hydrocephalus.
Hydrocephalus refers to the condition in which the accumulation of fluid takes place in the ventricles (cavities) deep inside the brain. The excess fluid enhances the size of the ventricles and applies pressure on the brain. The cerebrospinal fluid usually flows via the ventricles and bathes the spinal column and the brain.
Answer:
e. cutin
Explanation:
Plant exhibit many variations to withstand the temperature variations, desiccation and increased UV exposure which are some of the factors associated with land habitat. Cutin is a waxy substance that is found in the outer walls of the epidermal cells of plants. Cuticle in plants serves to make the outer most covering of aerial parts of the leaves and non-woody stem of herbaceous plants. The cuticle is made of cutin.
Cutin serves to protect the plant’s aerial surfaces from excess water loss. It also filters the excess UV light and thereby protects the underlying plant parts. The thickness of the cuticle varies in different plants depending upon the environmental conditions. The leaves of plants adapted to hot, dry climates have thick cuticles. The thickness of the cutin layer also varies in different parts of a plant. For example, the upper epidermis of leaf generally has a thicker cuticle than the shaded and relatively cooler lower epidermis.