Answer:
Answer B. Endosymbiosis
Explanation:
Early protists were first eukaryotic organisms and had several membrane bound organelles. The anaerobic protists evolved by acquiring purple bacteria. The purple bacteria have the ability to carry out aerobic cellular respiration. The endosymbiont transformed into mitochondria in due course of evolution. Similarly, the photosynthesizing protists were evolved by endosymbiosis of cyanobacteria which in turn was transformed into chloroplast during further evolution.
Answer:
C. Point B
Explanation:
The exposed curve represents a logistic growth model. Population growth depends on density. Natality and mortality depend on the population size, meaning that there is no independence between population growth and population density.
When a population grows in a limited space, density rises gradually and eventually affects the multiplication rate. The population per capita growth rate decreases as population size increases. The population reaches a maximum point delimited by available resources, such as food or space. This point is known as the carrying capacity, K.
K is a constant that equals population size at the equilibrium point, in which the natality and the mortality rate get qual to each other.
Referring to population size as N, when
- N<K, the population can still grow.
- N approximates to K, the population´s growth speed decreases.
- N=K the population reaches equilibrium,
- N>K, the population must decrease in size because there are not enough resources to maintain that size.
The sigmoid curve represents the logistic growth model.
- Point A: During this period, the population size is relatively stable. Little growth is expressed.
- Point B: At the beginning of this period, population growth increases softly. The more individuals are in the population, the more that reaches sexual maturity and get to reproduce, leaving fertile offspring. This fertile offspring also get to reproduce and leave more fertile individuals. At the end of the period, the curve shows a sharp slope, reflecting the significant increase in the population reproductive rate.
- Point C: At the beginning of this period, the population keeps on growing exponentially. But at the end of the period, the curve tends to stabilize, meaning that the population stops growing in size so fast. The population slow and gradually reaches the equilibrium point, K.
- Point D: The population got to stabilize.
The time period was called the Hadean Eon, and the rocks themselves are nearly 4.4 billion years old
The cell's series of tunnel-like membranes functioning in transport and storage are the Endoplasmic Reticulum.
What are the functions of the Endoplasmic Reticulum?
In both plant and animal cells, the endoplasmic reticulum is a network of tubules and flattened sacs that perform a number of tasks.
The structure and function of the two ER regions are different. Ribosomes are affixed to the cytoplasmic side of the membrane in rough ER. Ribosomes are not linked to smooth ER. The smooth ER is often a tubular network, whereas the rough ER is a collection of flattened sacs.
Rough Endoplasmic Reticulum (RER)
Endoplasmic Reticulum in rough shape. Membranes and secretory proteins are produced in the rough endoplasmic reticulum. Protein synthesis is carried out by translation on the ribosomes affixed to the rough ER. The rough ER generates antibodies in certain leukocytes (white blood cells). The rough ER creates insulin in pancreatic cells.
Smooth Endoplasmic Reticulum (SER)
The production of carbohydrates and lipids is one of many tasks performed by the smooth ER. Cell membranes must be built using lipids like cholesterol and phospholipids. Vesicles that deliver ER goods to various locations also use Smooth ER as a transitory place.
Hence, the correct answer is the Endoplasmic reticulum.
Learn more about the Endoplasmic reticulum here,
brainly.com/question/13474354
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