Explanation

Xylem and Phloem are specialized conducting tissues in vascular plants:

Xylem: Transports water and minerals from roots to other parts (unidirectional).

Phloem: Transports sugars (photosynthates) from leaves to other parts (bidirectional).

Explanation

Biology is classified as a natural science.

Because it studies living organisms and life processes through observation and experimentation.

Key Points:

Natural Sciences include:

1. Biology (study of life)
2. Physics (matter/energy)
3. Chemistry (substances/reactions)

Explanation

 In the human body, there are 3 pairs of false ribs on each side, corresponding to the 8th, 9th, and 10th pairs of ribs.

These ribs do not directly connect to the sternum (breastbone) like the true ribs (pairs 1-7).

Instead, their cartilage connects to the cartilage of the 7th rib, which is a true rib. 

Explanation

The periosteum is a fibrous connective tissue membrane that covers the outer surface of most bones, providing blood supply and contributing to bone growth and repair. 

Explanation

 The bronchioles are small branches of the bronchi, and they eventually end in tiny air sacs called alveoli where gas exchange occurs. 

Explanation

A respiratory surface must have a good supply of blood. 

A respiratory surface needs to be thin, permeable, and have a large surface area to efficiently facilitate gas exchange.

However, the crucial aspect is the blood supply.

The proximity of blood capillaries to the respiratory surface allows for the rapid transfer of oxygen from the air to the blood and carbon dioxide from the blood to the air. 

Explanation

The exoskeleton of coelenterates is made of Calcium carbonate. 

Coelenterates like corals primarily have exoskeletons composed of calcium carbonate

Explanation

Viruses are microscopic particles that require a host cell to replicate.

Mycoplasma, while small and sometimes considered a pathogen, is a type of bacteria.

Bacteria are capable of independent replication, unlike viruses which need to infect a host cell to reproduce. 

Explanation

Light intensity refers to the amount of light energy reaching a plant's surface per unit time.

This directly impacts the rate of photosynthesis as more light energy available means more ATP and NADPH can be produced, driving the Calvin cycle

Higher light intensity generally leads to increased photosynthetic activity. 

Explanation

 Nucleic acids are composed of nucleotides.

NTPs (Nucleoside Triphosphates) are a type of nucleotide.

They consist of a nitrogenous base, a pentose sugar (ribose in RNA or deoxyribose in DNA), and three phosphate groups

Nucleic acids like DNA and RNA are built from chains of these nucleotides.