Answer:
A cell is defined as the structural and functional unit of an organism.
The average size of the prokaryotic cell lies between 0.1 to 10 micrometers whereas the average size of the eukaryotic cell is approximately 25 micrometers.
Four things are found in all the cells: genetic material (either DNA or RNA), cell membrane, cytoplasm, and the ribosome.
All the living cells grow and reproduce (sexually or asexually) and have the ability to respond to stimuli.
Thus, characteristics of a cell may include: cell grows and reproduces, responds to stimuli, contains DNA or RNA, not both , and contains a cell membrane.
Answer;
-DNA molecule
Explanation;
-According to cell theory; All known living things are made up of one or more cells. All living cells arise from pre-existing cells by division. The cell is the fundamental unit of structure and function in all living organisms.
-The modern version of the Cell Theory includes the ideas that:
-
Energy flow occurs within cells.
- Heredity information (DNA) is passed on from cell to cell.
- All cells have the same basic chemical composition.
-Therefore the study of DNA molecule was instrumental in the formulation of the modern cell theory.
Answer:
Crossing over
Explanation:
Crossing over is the process during which two chromatids of two homologous chromosomes exchange part of their genetic segments. It occurs during the pachytene stage of prophase I of meiosis I.
Linked genes are mostly inherited together and do not exhibit independent assortment. However, when linked genes are present far apart from each other on the same chromosome, crossing over can occur between them to produce recombinant chromatids. Therefore, crossing over can break the linkage and produce recombinant progeny as it occurs during the independent assortment of unlinked genes.
Answer: herbivore, eukaryote, primary consumer
Explanation:
The red squirrel can be described by the following features.
1. Herbivore: A herbivore is an animal which is dependent upon the plant and their products for it's food requirement. Here, the red squirrel is the herbivore because it is dependent upon the spruce tree seeds for their food requirement.
2. Eukaryote: A eukaryotic organism is the one which has well define nucleus and encloses the genetic material in the nucleus. The red squirrel is a complex eukaryotic organism.
3. Primary consumer: In a food chain a primary consumer is an organism which is dependent upon plants and their food products for energy and food needs. The red squirrel is the primary consumer this is because of the fact that it consumes on the seeds of the spruce trees.
