Answer: d. both a and c
Explanation:
Green algae are present in the most diverse environments. The vast majority of species, approximately 90%, are freshwater, with a cosmopolitan distribution, that is, they have a wide distribution on the planet. It is the predominant group of freshwater plankton. BASIC CHARACTERISTICS: Eukaryotic, Chlorophyll a and b, Xanthophylls (mainly lutein) and Carotenes (mainly β-carotene), Reserve: starch, Cell wall: mainly cellulose, Presence of flagella at some stage of the life cycle.
Red algae: Cell wall - consists basically of two parts, one internal and rigid, formed by cellulose microfibrils (most red algae), and the other outer, mucilaginous, formed by galactan polymers, such as agar and carrageenans. Certain groups of red algae have calcium carbonate deposition on the wall, giving the stalk great rigidity. This deposition may be in the form of aragonite or calcite. BASIC CHARACTERISTICS: Eukaryotic, Chlorophyll a and Phycobiliproteins (b, re-phycoerythrin, allophycocyanin and echo-cytocyanin), Xanthophylls (zeaxanthin, lutein, etc.) and carotenes (mainly β-carotene), Reserve: Cellular starch: cellulose, agar and carrageenan, Absence of flagella at all stages of life, including gametes and spores.
Bone marrow contains stem cells that give rise to all of yur blood cells.
Answer:
Closed system.
Explanation:
Robot is an closed system because there is no transfer of mass but transfer of energy occurs from robot to its surrounding. According to the definition of closed system, closed system is a type of system in which there is only transfer of energy occurs while in open system both mass and energy can be transferred from the system to their surrounding. So no mass transferred from the robot only energy in the form of mechanical energy is transferred.
Answer:
Nucellus makes the most of the ovule. It encloses the embryo sac. They have abundant food reserves and therefore act as nutritive tissues for the embryo in some plants.
