In biology, the strain is a low-level taxonomic rank used in different contexts:
In microbiology, a strain is a part of a bacterial species different from other bacteria of the same species by a minor but identifiable difference. Strains are often created in the laboratory by mutagenesis existing strains or wild-type examples of bacterial species.
In zoology, a strain corresponds to an individual or group of individuals who are at the origin of a line of descendants, sometimes called the holotype, paratypes, etc. A strain is a population of organisms that descends from a single organism or pure isolate culture. Strains of the same species may differ slightly from each other in many respects.
A strain thus consists of a group of organisms of the same species possessing certain differential traits based on their relationship; either they come from the same region, as the same watershed of a river, or they are the fruit of a particular breeding program (exists as a whole interbreeding without introductions from external sources).
1.The enzyme pepsin.Pepsin breaks down proteins in the stomach
2 Im pretty sure its the duodenum and the ileum
Which of the following species reproduces by internal fertilization?
a) cats
(b) Toads
(c) The fish
(d) alternative b and c
Answer:
(a) Los gatos
Explanation:
Only cats are capable of internal fertilization from the given choices above.
Internal fertilization is the fusion of gametes within an organism. This process occurs during sexual reproduction within the female.
- Toads and fishes exhibit external fertilization.
- External fertilization occurs where the male sperm externally fertilizes the eggs of the female.
- This usually takes place in a moist or wet place especially water bodies. The liquid medium will transport the sperm to the egg.
In cats, the female specie takes in reproductive cells from the male during coitus and it fertilizes the her eggs to produce a zygote.
Answer:
There are three main types of blood vessels:
1)Artery ---
i) It is a blood vessel having a thick wall.
ii) It carries blood from the heart to different parts of the body.
iii) On regulatory demand of the body it can dilate or constrict.
iv) It doesn't contain any valve.
v) All arteries carry oxygenated blood except the pulmonary artery.
2)Vein ---
i) It is a blood vessel having a thin wall.
ii) It brings blood from different parts to the heart.
iii) It can't dilate or constrict under normal conditions.
iv) It contains valves that allow the blood to flow in one direction towards the heart.
v) All veins carry deoxygenated blood except the pulmonary vein.
3)Capillary ---
i) It is a very narrow blood vessel that has very thin walls.
ii) It forms a network throughout the body in all living cells connecting arteries to veins.
iii) It can dilate or constrict according to the requirement of tissue.
iv) It doesn't have any valve.
v) It contains mixed blood as it connects arteries and veins
I’m assuming it’s all of the above
