Answer:
Maybe as a producer can be a tree or grass
Explanation:
therefore i think there can be more than one
Answer:
Please find the explanation below
Explanation:
Sexual reproduction is the kind of reproduction that requires two organisms (male and female) to form an offspring. The male organism produces gametes called SPERM while the female organism produces gametes called EGG. These two gametes come together in a process called FERTILIZATION to produce a zygote, which develops into an offspring.
In sexual reproduction, gametes are produced by organisms involved via a process called MEIOSIS. Meiosis, however, reduces the chromosome number of the gametes by half. However, one process unique to only meiosis and sexual reproduction is called CROSSING OVER.
Crossing over is the process whereby chromosome segments is exchanged between non-sister chromatids of homologous chromosome. This process causes a recombination of chromosomes (alleles) in such a way that the gametes will be genetically different from the parent organisms (genetic variation). According to this question, sexual reproduction leads to more genetic variation than asexual reproduction due to the process of CROSSING OVER that occurs in sexual reproduction.
Answer:
it is D
What global climatic change gave gymnosperms an advantage over ferns?
A) Increased fluctuations in global climate
B) the climate becoming hotter and wetter
C) the climate becoming cooler and drier
D) the climate becoming hotter and drier
Chloroplasts. Animal cells don’t have chloroplasts only plants
Answer:
Having considered how an appropriate primary immune response is mounted to pathogens in both the peripheral lymphoid system and the mucosa-associated lymphoid tissues, we now turn to immunological memory, which is a feature of both compartments. Perhaps the most important consequence of an adaptive immune response is the establishment of a state of immunological memory. Immunological memory is the ability of the immune system to respond more rapidly and effectively to pathogens that have been encountered previously, and reflects the preexistence of a clonally expanded population of antigen-specific lymphocytes. Memory responses, which are called secondary, tertiary, and so on, depending on the number of exposures to antigen, also differ qualitatively from primary responses. This is particularly clear in the case of the antibody response, where the characteristics of antibodies produced in secondary and subsequent responses are distinct from those produced in the primary response to the same antigen. Memory T-cell responses have been harder to study, but can also be distinguished from the responses of naive or effector T cells. The principal focus of this section will be the altered character of memory responses, although we will also discuss emerging explanations of how immunological memory persists after exposure to antigen. A long-standing debate about whether specific memory is maintained by distinct populations of long-lived memory cells that can persist without residual antigen, or by lymphocytes that are under perpetual stimulation by residual antigen, appears to have been settled in favor of the former hypothesis.
