Sickle cell anemia is a genetic condition that distorts the shape of the hemoglobin. This reduces the capacity of the red blood cells to carry oxygen. Another effect is that the distorted red blood cells come together forming a heavy and compact collection of cells that can block the flow of blood. The sedimentation rate is increased by sickle cell anemia.
Answer: 1. a. logistics model of growth
2. a. environmental conditions
3. b. all limiting factors
4. b. water availability
Explanation:
1. a. logistic model of growth will show the increase in population of a species in accordance with the carrying capacity exponentially but when the population will experience the scarcity of resources it will decline considerably.
Carrying capacity is the total number of members of the population of a species that an ecosystem can sustain by providing resources.
2. b. All environmental conditions which favor the survival of the living beings will contribute to the carrying capacity for example food, water, shelter, and other resources.
3. b. Limiting factor is the one which limit the chances of survival and growth of a particular species in an ecosystem. For example, scarcity of food, here food is the limiting factor.
4. d. A density dependent limiting factor is the one which affects the population of the species based upon the density. The water availability is a density dependent limiting factor because the more the density or abundance of a population more will be the scarcity of water as it will be required by all organisms. So, the species population may experience decline due scarcity of water.
Helper T cells <span>are required for almost all </span>adaptive immune responses<span>. They not only help activate B </span>cells to<span> secrete antibodies and macrophages </span>to<span> destroy ingested microbes, but they also help activate cytotoxic </span>T cells to<span> kill infected target </span>cells<span>.</span>
Answer:
Chromosome condenses
Pairing up to form tetrad
Crossing over
Lining up on metaphase plate
Homologous chromosome separate
Explanation:
Condensation of chromosomes occurs in prophase I phase. Pairing up to form tetrad occur during prophase I. Crossing over occurs during prophase I of meiosis cell division. Chromosomes line up along the metaphase plate in the stage of Metaphase. Centromeres break down and homologous chromosomes separate in anaphase I phase of meiosis.
